iRV2 Forums

iRV2 Forums (https://www.irv2.com/forums/)
-   Cummins Engines (https://www.irv2.com/forums/f123/)
-   -   Cummins ISC lift pump replacement (https://www.irv2.com/forums/f123/cummins-isc-lift-pump-replacement-280226.html)

crah 02-22-2016 02:12 PM

Cummins ISC lift pump replacement
 
Well I've been hit with the dreaded lift pump leaking. I have a 2003 Holiday Rambler coach on a 2002 Roadmaster chassis with a cummins ISC 350. The pump was quite hard to access with some wiring looms in the way. I searched the forum and found that tightening the bolts sometimes does the trick. My bolts were all tight so looks like I need a replacement. Anyone have a part number and source to get these pumps from? Any pointers on the replacement? Looks like 4 mounting bolts and I couldn't really see the other connections well. I'm sure there is a fuel input/output and maybe a wiring harness?

jacwjames 02-22-2016 08:44 PM

I don't have a leak but have been doing some research in preparation in the event I get one.

If you haven't already join the Cummins Quickserve site, once you register out in you engine serial number. it will bring up some screens, go the parts, fuel systems, Accessories, Fuel transfer pump. It will give you the appropriate part number.

Cummins has changed the part several times so using the Quickserve site will give you the right one.

My part number is 4935005 and will cost ~$375 depending on where you get it. This is the complete assembly including the mount.

Back in the mid 2000's after the ULSD was put on the market there was a rash of fuel pump failures. The low sulfur fuel would cause a gasket failure in the fuel transfer pump. Cummins put out a bulletin instructing service shops to replace the gasket however they stopped doing this as a gasket cost $7 with 1/2 hour of labor versus the new transfer pump.

I found my gasket number is 4928511 and am searching for a place to buy it, found one place that I will confirm this week. I intend to buy a gasket to have as spare.

Keep us posted on your fix

CountryFit 02-22-2016 08:55 PM

can you look at where the leak is at? you might need a mirror or video camera to see it. most likely the leak is from the gasket between the pump and the mounting bracket. i remember there are 3 bolts holding the pump, if those are very right as you said, chances are the gasket is torn. get that replaced, you might resolve the problem.

John Jones 02-22-2016 09:43 PM

Keep us posted on where to buy the gasket. I might get a couple for myself!

AFChap 02-23-2016 09:29 AM

I had a Cummins SE location replace mine. They did it from the top via the under the bed/closet access holes.

crah 02-23-2016 10:28 PM

Thanks all for the info. I will order a new pump this week sometime and hopefully get it changed out soon.

jacwjames 02-24-2016 10:08 AM

I just placed an order for the gasket, I ordered it from

Phone # 1-800-247-5673
Clarence Henley
Capital Volvo Trucks & Mitsubishi
Capital Trailer & Equipment Co., Inc.
Capital Exports of the US
www.capitalvolvo.com

Price was $6.71 plus shipping, he was going to try and ship it USPS instead of UPS.

This is not a OEM part but aftermarket gasket. I don't think Cummins even sells this part.

Here is a link to the service bulletin,
https://www.alpinecoachassociation.co...ft%20Pumps.pdf
I searched the Quickserve site and this bulletin isn't even available anymore. It lists 2 different gaskets but the Capital Volvo shop said the 2 numbers interchange.

I have ordered one of the gaskets and will keep it as a spare just in case. I plan to check the transfer pump on a regular basis for leaks.

Dave Fernandez 02-24-2016 02:05 PM

I replaced my lift pump last year on 2001 Alpine 38ft MH. Because of the island bed the procedure was not to difficult. It took me 4 hours because it was over 100 outside and humid. Because I was working on the engine with the cover open for access I was stuck with heat and humidity. If I had only replaced the gasket and it did not work I would have been real mad. Just because all the work to R&R for just a gasket.

I am glad I replaced the entire pump assembly now no worries. The new pump was designed to operate with the ULSD.

I also replaced all of the O rings on the fittings with the upgraded O rings for use with ULSD.

Now I do have any worries about the pump and fittings leaking.

hypoxia 02-25-2016 08:38 AM

Quote:

Originally Posted by jacwjames (Post 2951939)
This is not a OEM part but aftermarket gasket.

A bunch of folks would benefit if you show the part & packaging, manufacturer etc. when you get it. I'm curious to see if it is a paper or rubber type gasket.

Coma 02-26-2016 02:38 PM

The pump is also prone to leaking at the electrical inlet, no gasket for that. The new pump is configure differently than the old one, so you will need assorted adapters and plugs to make it work.

It was about $400 labor to have it put in.

jacwjames 02-28-2016 07:51 AM

I received the transfer pump gasket in the mail yesterday. I is packaged in a small plastic type bag and has Genuine Cummins Parts with the Cummins Insigna and is dated 9/18/06. This is close to the date range of the TSB that I found on Cummins. (note the sales person said that they had the gasket made and would be and after market part).

The gasket is made of a heavy rubber type material.

Anyway, I'm keeping the gasket just as insurance (cost $7.71 including shipping) in case I'm stuck on the side of the road. I would repair and then when I get home change out the lift pump.

Unfortunately Cummins no longer just sells the lift pump but you have to buy the entire mounting assembly for an outrageous price.

passerby 03-23-2016 08:14 PM

1 Attachment(s)
Mine to is leaking. Ordered one today. I noticed something was leaking, just tracked it down. :eek:

USMCRET 03-24-2016 06:11 AM

Where is this lift pump generally located on these engines?

passerby 03-25-2016 07:21 PM

Mine is on passenger side, halfway between top and bottom of engine. It has lots of hoses.

Smitty77 03-26-2016 04:16 PM

9 times out of 10, a new Lift Pump will cure the ULSD caused problems on these older engines.

Our July 2003 ISL370 CAPS engine Lift Pump was not leaking, but I decided to preventatively work around it on my schedule. I had Brazel's add the FAAS pump into our system. Alan, nice guy and attention to detail tech, did a great job of retaining my existing Country Coach filters (I only installed the FASS pump, not the their dual filters.) in our fuel filter basement bay. Fabricated lines to run up and splice into the existing Lift Pump (The top part, past the risk of gasket leaking cocnerns.). He capped off and double secured the existing lift pump lines, so that if I ever needed to I could re-activeate the OEM Lift Pump by shifting the hoses back into play. (This would only be done for a short emergency reason.).

Very clean install, and I like that the FASS pump is keeping positive pressure feed to the CAPS. The CAPS lives and breathes by the fuel flow for both cooling and lubrication. Yes, it is supposed to draw al that it needs, this the OEM Lift Pump shuts down once it is up and running. But I feel like I have extra insurance with the positive fuel flow pressure.

Best to all,
Smitty

passerby 04-05-2016 08:16 PM

2 Attachment(s)
New pump installed.:dance:
Part #4935005 Cummins
$488.88 + tax & shipping
Photo of new one installed and
old nasty one on the ground

USMCRET 04-06-2016 03:07 PM

How long did it take you to install that?

CountryFit 04-06-2016 10:21 PM

Quote:

Originally Posted by passerby (Post 3009562)
New pump installed.:dance:
Part #4935005 Cummins
$488.88 + tax & shipping
Photo of new one installed and
old nasty one on the ground

congrats... did you need to get a bunch of adapters/connectors or just plug n' play?

passerby 04-07-2016 07:24 PM

Before you give me too much credit, I had someone install the pump.
Where I work we have 40 + MHs and so I meet all kinds of tradesmen. He does roadside repairs and had come to our storage to fix another MH. I had him install the pump.
My claim to glory, I went and bought the copper washers. It took him about 2 hours and some muscle. He use the old plugs from the leaking pump. (more holes in pump than hoses to connect) I will post the washers parts tomorrow the receipt is at work. I had easy access to Motor. I do a lot work myself but didn't do this job. All is good now:)

CountryFit 04-08-2016 12:04 PM

Quote:

Originally Posted by passerby (Post 3012525)
Before you give me too much credit, I had someone install the pump.
Where I work we have 40 + MHs and so I meet all kinds of tradesmen. He does roadside repairs and had come to our storage to fix another MH. I had him install the pump.
My claim to glory, I went and bought the copper washers. It took him about 2 hours and some muscle. He use the old plugs from the leaking pump. (more holes in pump than hoses to connect) I will post the washers parts tomorrow the receipt is at work. I had easy access to Motor. I do a lot work myself but didn't do this job. All is good now:)

super deal! mine had been leaking and i tightened the bolts which did the trick. i am not sure how long it will hold, sooner or later i will need to replace either the gasket or the pump assembly. if you could share what miscellaneous items you bought for it, that would be great!! tia!.

colo.kids 04-09-2016 10:57 AM

Quote:

Originally Posted by CountryFit (Post 3013460)
super deal! mine had been leaking and i tightened the bolts which did the trick. i am not sure how long it will hold, sooner or later i will need to replace either the gasket or the pump assembly. if you could share what miscellaneous items you bought for it, that would be great!! tia!.

I have a 2004 Country Coach Inspire with ISC and yesterday saw fuel leaking at the rate of a drop or two every 10 seconds or so. Based on this discussion and other research I suspect the transfer pump though I have yet to tear apart the bedroom to see the engine and the source of the leak. With 82,000 miles is the transfer pump and or gasket the most likely source of the leak, and if so how do I get the right part number? Can a person with moderate skills do the install as I hate to think of the cost of having Cummins do the work.

Thanks

CountryFit 04-09-2016 03:13 PM

Quote:

Originally Posted by colo.kids (Post 3014777)
I have a 2004 Country Coach Inspire with ISC and yesterday saw fuel leaking at the rate of a drop or two every 10 seconds or so. Based on this discussion and other research I suspect the transfer pump though I have yet to tear apart the bedroom to see the engine and the source of the leak. With 82,000 miles is the transfer pump and or gasket the most likely source of the leak, and if so how do I get the right part number? Can a person with moderate skills do the install as I hate to think of the cost of having Cummins do the work.

Thanks

you can tighten the bolts to see if it stops. the access is from top (flip up the bed mattress).

you can call cummins with your engine serial number to find out the gasket number. (flip up the threads, a member posted his findings).

this can be a diy project in case you need to replace the gasket or a new pump. if you need to hire someone to do it, any diesel shops or heavy truck companies will be able to do it.

colo.kids 04-09-2016 09:14 PM

Quote:

Originally Posted by CountryFit (Post 3015078)
you can tighten the bolts to see if it stops. the access is from top (flip up the bed mattress).

you can call cummins with your engine serial number to find out the gasket number. (flip up the threads, a member posted his findings).

this can be a diy project in case you need to replace the gasket or a new pump. if you need to hire someone to do it, any diesel shops or heavy truck companies will be able to do it.

Thanks for answering my questions and for the advice.

Russ

passerby 04-11-2016 08:02 PM

The only parts for lift pump replacement, 4 copper crush washers for the banjo connection from pump to engine. They are on the top of pump and I looked at the receipt no size listed, just 4 about $6.00 total.

AccessMaster 04-19-2016 01:37 PM

Pump gasket
 
I ordered the 4928511 gasket, but I do not yet understand where it goes.
i can only view the top of my pump, so I do not yet understand the entire system.

CountryFit 04-19-2016 03:44 PM

Quote:

Originally Posted by passerby (Post 3018561)
The only parts for lift pump replacement, 4 copper crush washers for the banjo connection from pump to engine. They are on the top of pump and I looked at the receipt no size listed, just 4 about $6.00 total.

thanks for the info.

crah 04-19-2016 08:08 PM

2 Attachment(s)
Quote:

Originally Posted by AccessMaster (Post 3030157)
I ordered the 4928511 gasket, but I do not yet understand where it goes.
i can only view the top of my pump, so I do not yet understand the entire system.

Here's a picture of a new pump. The 3 screw that look exactly same on the top are the ones you remove and the gasket goes between the top mounting bracket and the bottom pump. The old style pump you have is the same set up but the screws are different. They are actual bolts you can remove with a socket.

crah 04-19-2016 08:10 PM

1 Attachment(s)
One more picture. It's the star looking screws.

CountryFit 04-19-2016 09:07 PM

crah, great info... does the "new star screws" have the same thread as the old bolts'?

crah 04-21-2016 11:32 PM

Quote:

Originally Posted by CountryFit (Post 3030778)
crah, great info... does the "new star screws" have the same thread as the old bolts'?

That I'm not sure of. I had a mobile mechanic Install the new pump. It would have taken me a weekend to do myself with lots of cursing. I did try to tighten my old pump bolts but had no success with that. Looking back at it, I may have attempted to replace just the gasket if I had one one hand but I happen to be by a cummins shop and decided to buy the entire pump assembly.

AccessMaster 04-22-2016 10:31 AM

Thank you guys.
 
Thanks for all the great input on the lift pump issue. At the moment I am one of the lucky ones. I tightened the three bolts and the leak stopped. I have the gasket on the way as well.

Thanks again. You guys are awesome.

cewarre 03-06-2018 03:15 PM

Lift Pumps are Still Failing Out There
 
I too woke up one recent morning to a puddle of diesel under my coach. I spent lots of time on iRV@ and decided to try replacing the gasket first and then if there is still a problem, purchase a new pump. I followed a posting by jacwjames (which I greatly appreciate) and have the following update:

I spoke with Carl at Capital Volvo, 1-800-247-5673 and he said he still has 370 of the aftermarket gaskets in stock for the Cummins lift pumps and gets calls quite often. They are still $6.71 each and he is shipping me two via UPS. He said the aftermarket gaskets reference to Cummins part numbers 3964385 and 4935004.

snowman1 03-07-2018 08:24 PM

I recently had mine replaced by a mobile mechanic. Took him about 2 hours to do it. Mine wasn't leaking or hard to start, just decided to do it as a preventative type maintenance. The new lift pump is nearly silent from inside the coach during the priming, the old one was very loud I could clearly hear it. When we first turned the ignition on to start the priming sequence, I had to go back to the open hatch to hear it. Was worried something didn't get hooked properly. Starts right up like before and is one more thing to check off my worry list.

While he was unpacking the new one from the box noticed it had a "Made In China" sticker on it. A lift pump for a Cummins diesel engine? We really don't make anything here anymore. Kept the old one just in case...

rgvtexan 06-04-2018 08:54 PM

Anyone use this pump? <$200.00

Cummins 4935005 Fuel Transfer Pump - Carp Coastal Marine Supply

guardrail53 06-04-2018 10:03 PM

Quote:

Originally Posted by rgvtexan (Post 4225333)

Same #, does not come with the gasket and the brass hose washers! Said the guy in the review? He also said that it worked perfectly! Sooooooo!!

I would order it, for the cost savings! And source the gasket and washers!

Rail!:cool::D

jbenalpine 06-18-2018 09:54 AM

1 Attachment(s)
My 330 HP ISC from the year 2000 had the much talked about Lift Pump leak. The bolts talked about I had tightened earlier without success.
I ordered a gasket from Capital Volvo and fuel line crush washers from Cummins (2 x 3963983 and 2 x 3963988) to repair my leaky pump. The pump a bit tough to get out and back in but otherwise the job is DIY kind of job taking about 4 hrs for whole process. Taking the pump apart the gasket and the fuel line washer were all swollen from fuel. Replaced those parts for total cost $21.65 and after 3 weeks and a few hundred miles no leaks. Hoping it remains that way.:o

scotcee 06-18-2018 09:58 PM

Noticed fuel on driveway when we pulled out for our 2200 mile trip to visit all our families. Found a mechanic in a town 50 miles away (southern Calif. has 10,000,000 diesel rigs and maybe 100 mechanics to fix'em).
Pump--$420.83 Labor--$125.
Will check to make sure all gaskets, o-rings, and hoses are ULSD.
First engine breakdowm with 80000 miles on an 2004 ISC
8.3L.

jimmy braden 03-04-2019 07:26 AM

Mine only has the Bedside hatch access to pump. I think im just gonna let a professional do the work. I found one local guy that will do it for 105per hour labor.. And I bet he's 3x faster than I so I can prob afford that.. Looks like pumps are about 250now.

thebings 10-11-2019 04:32 AM

Just received a new replacement pump. Was hoping to use the old plugs to fill the unused ports on the new pump. The old pump does not have removable plugs. Anyone know where the size or part number or where I can buy these plugs. I need three plugs, the two at the rear of the pump and the forward most port on the passenger side. I have already tried HD and auto parts store.
Thank
Don

thebings 10-11-2019 10:19 AM

UPDATE:
Quote:

Originally Posted by thebings (Post 4992242)
Just received a new replacement pump. Was hoping to use the old plugs to fill the unused ports on the new pump. The old pump does not have removable plugs. Anyone know where the size or part number or where I can buy these plugs. I need three plugs, the two at the rear of the pump and the forward most port on the passenger side. I have already tried HD and auto parts store.
Thank
Don

Found the Plugs at Cummins. All is good

imnprsd 11-04-2019 11:28 PM

1 Attachment(s)
I know you just repaired your Lift Pump and are good to go, but for others facing this problem I would recommend you by-pass the lift pump altogether (if you can) and put your money and time into a new FASS TS (Electric) Pump installation.

See other posts on how to install the FASS pump and protect your very expensive CAPS injection pump!

The picture shows who I had to install the TS Pump in my Itasca-Freightliner RV. The Pink Highlighter shows how Monaco-Spartan owners can by-pass the lift pump altogether.

Damion 11-05-2019 06:10 PM

I replaced mine with this one $234.13
Did 10,000 miles to Alaska this summer to try it out!
https://www.mddistributorsstore.com/...-transfer-pump

imnprsd 11-05-2019 10:32 PM

Yeah, but your Lift Pump only runs for the first 30 seconds that you start your motor and then it shuts down.

But lift pump purpose is the prime the injection system so the low pressure gear pump can take over and suck fuel from the fuel tank.

The FASS fuel pump runs constantly while your engine is running... that's the point!

The FASS TS fuel pump has two additional filters... and recycles fuel to your tank which removes. algae and other contaminants.... and that's the point

Ray,IN 11-16-2019 10:09 PM

Quote:

Originally Posted by imnprsd (Post 5026568)
Yeah, but your Lift Pump only runs for the first 30 seconds that you start your motor and then it shuts down.

But lift pump purpose is the prime the injection system so the low pressure gear pump can take over and suck fuel from the fuel tank.

The FASS fuel pump runs constantly while your engine is running... that's the point!

The FASS TS fuel pump has two additional filters... and recycles fuel to your tank which removes. algae and other contaminants.... and that's the point

You've almost convinced me into having a FASS pump installed on my MH. I can no longer perform such work, age and health issues have prevailed.
The downside, the HDT repair shop who does all my MH chassis work charges $135/hr.

imnprsd 11-18-2019 01:40 AM

Damion: The purpose of the FASS "TS" Pump is to protect your CAPS injection system from failure. It has nothing to do with competing with a stock lift pump. The 2nd purpose is therefore to render the stock lift pump "OBSOLETE".

I think if anyone is facing the option of replacing a OEM Lift Pump vs. spending a few extra $$$ on a FASS "TS" Pump (KIT) that there are many more reasons to do this than to replace what you have.

Please share with us the cost of replacing your stock lift pump?

Ray, In: I can never tell what your purpose is? Sometimes you have positive and helpful comments, but in this case I cannot tell what you mean to contribute. Maybe you are just making a personal "decloration," but even so how does that help other people faced with fixing their Lift Pump or considering the option of upgrading to a FASS lift pump?

I do like that you are always "online" and I'm sure you fundamentally like to help people, but why you consistently seek to trash my posts or derail the central message in my posts/threads are confusing at best. Might I suggest you lean more to the "optimistic" side in the future -- when you don't know what you want to say rather than to talk about the "negative" or try to add sarcasm.

My guess is that you do not see yourself doing many more trips in the future. Therefore, a FASS fuel pump offers you little or no "security." But for the rest of us it does... and I think you know it does! So why don't you just say so?

I hope you don't give into the "dark side" any more... when you have so much more to offer! That's my advice. And in general I do like hearing form you!

I hope you continue to help other people on this website, because I'm all "petter'd out." My plan is to step away from IRV2 for 6 months or so. (If I can.) Therefore, if you truly think my threads and posts are helpful, please refer people to them. Thank you!

Ray,IN 11-18-2019 10:35 PM

imnprsd, to which of my replies are you referring, #44?

imnprsd 11-27-2019 02:25 AM

How your isc-caps pump works (video)
 
1 Attachment(s)
Video:

https://www.youtube.com/watch?v=xp-YuZ5uQYY

Ray,IN 11-27-2019 11:09 PM

That is a great video and explanation, thanks for posting the video!

Ray,IN 12-06-2019 08:55 PM

imnprsd, I just brought my MH home today. The primary pump was leaking, bolts were tight. I asked about installing a FASS pump and was told it would be $1,000 more than a new OEM pump(installed).DW nixed that right away so I had an OEM pump installed.Their only access to the pump was to remove the starter first due to Spartan MM GT frame design.

imnprsd 12-06-2019 11:06 PM

FASS or AirDog UPGRADE
 
2 Attachment(s)
RAY,IN: Please share details of your lift pump repair so other people can benefit from your experiences:

* What type of RV and Chassis and engine do you have?

* Do you have 1 or 2 fuel filters? (Since you quoted a FASS cost to upgrade.)
a
* Do you have one of those pre-2003 Cummins engines with a lift pump gaskets that are prone to deterioration with ULSD Fuel?

* Are you replacing just the gasket or the lift pump?

* Can you describe the leak... and send pictures?

* Did you go to Freightliner?

* What was the total cost of your repair?

* Other details: I always thought dropping the starter would be a good idea to gain access to the lift pump. What is involved to do this?

Did you ever give any thought to replacing the Stator since you were in that area?

The Stator is the electrical part of the ICV that is controlled by the ECM. And those 6 ICV pins meter fuel to the distributor that feeds each of the 6 cylinders.

And since you are going to remove the starter motor, which will give you easy access to this area, I think the Stator should be easily accessed. (Only 4 bolts.)

I also know the STATOR can fail and when it does it can also take-out your ECM, because that Suppressor Diode will not be enough to "block" the electrical spike a failed Stator sends to the ECM.

FYI, Cummins makes a STATOR kit for ~$100. (Part #4089399) ... But I guarantee that if you ask a mechanic about this the answer will be: "We don't like to replace necessary components." So this is something you will have to ask about and push if you want it done for preventative maintenance (insurance).

FAULT CODES: #277 is the Stator Circuit, #539 is the suppressor, and #111 may or may not be the ECM.

Any CAPS component failure will leave you stranded, inconvenienced, sucked bone dry by any repair facility who can get you back on the road in a couple weeks, and ECMs are very expensive. (Not to mention the $1,000s in tow costs.)

...So yes! I think it does make sense to replace the Stator for if you are this far into your project. ($100 plus 30 minutes labor.) ...But I would also concede that NOT replacing the Stator is perfectly sound too. It's a judgement call most people don't make because they don't even know what a Stator is or does. ...But now that you do, the decision is yours (and everyone else who reads this post).

TenMillie 12-07-2019 12:47 PM

Quote:

Originally Posted by cewarre (Post 4072422)
I too woke up one recent morning to a puddle of diesel under my coach. I spent lots of time on iRV@ and decided to try replacing the gasket first and then if there is still a problem, purchase a new pump. I followed a posting by jacwjames (which I greatly appreciate) and have the following update:

I spoke with Carl at Capital Volvo, 1-800-247-5673 and he said he still has 370 of the aftermarket gaskets in stock for the Cummins lift pumps and gets calls quite often. They are still $6.71 each and he is shipping me two via UPS. He said the aftermarket gaskets reference to Cummins part numbers 3964385 and 4935004.

Do you have to remove the pump to install a new gasket?
Mine started leaking to, tightened the bolts and all is well for now but will be getting the gasket.

Ray,IN 12-07-2019 09:06 PM

Quote:

Originally Posted by imnprsd (Post 5065951)
RAY,IN: Please share details of your lift pump repair so other people can benefit from your experiences:

* What type of RV and Chassis and engine do you have? All that is in my signature.

* Do you have 1 or 2 fuel filters? (Since you quoted a FASS cost to upgrade.) Price quoted me was $1,000 more than replacing the OEM pump, I declined.
a
* Do you have one of those pre-2003 Cummins engines with a lift pump gaskets that are prone to deterioration with ULSD Fuel?Yes, all bolts were tight. I brought old pump home, will replace gasket-if that was cause of leak, and keep for spare.

* Are you replacing just the gasket or the lift pump? Pump was replaced with new OEM Cummins pump.

* Can you describe the leak... and send pictures? Starter was wet with fuel, no pics, I am physically unable to DIY @ 77 W/ COPD.

* Did you go to Freightliner? Independent HDT repair shop.

* What was the total cost of your repair? $1,600

* Other details: I always thought dropping the starter would be a good idea to gain access to the lift pump. What is involved to do this? Removing the starter was the only access to the primary pump, due to Spartan bus chassis_ MM GT frame design. I paid to have everything performed, I was not onsite.

.

Sorry for the unusual reply, that was the easiest way for me. Our MH is back home today.
I was not happy with the cost, but had no option other than take our MH to Camping World :nonono:. I think I was charged 2 hrs labor for removing the starter, 2 more for replacing starter.(took 2 mechanics 1hr, one to support, 1 to do the wrenching.) They did this laying on creepers. Pump was over $700 from Cummins.

imnprsd 12-07-2019 09:52 PM

Ray, IN: Sorry you got "hosed" on the cost of parts; and that your repair was so expensive because your Chassis required the mechanic to drop your Starter.

I have a Freightliner Custom Chassis and it too has a rail that runs right next to the ECM and lift pump.

Other owners mentioned they only paid $239 for the lift pump and $125 for labor, but I don't think this is common for us Winnebago/Itasca owners.


https://www.mddistributorsstore.com/...-transfer-pump

I think what people need to know is:

* The lift pump gasket is the most likely source of your fuel deliver problems (engine starvation) that leads to engine sputters when accelerating or climbing a grade, or even no-start conditions, because the vacuum pressure drops below -5PSI.
...And then the gear pump cannot suck enough fuel from the tank; which if you lucky your engine will just quit. Bit if you are unlucky your CAPS pump will fail in any number of ways.

* The gasket in pre-2002 Cummins engines is less tolerant to ULSD fuel vs the 2003 and new models. In these older engines (like Ray,IN) the gasket will deteriorate and tightening those 3 lift pump bolts may not (probably will not) work.

There is a Cummins Service Bulletin to this effect on how to replace the lift pump gasket.

* Most people who have claimed the lift pump failed have that wrong. It was the gasket that failed, but the mechanic told them it was the lift pump because no one will pay $1,600 to replace a gasket.

* Cummins likes to charge an arm and a leg every chance they get. And don't be fooled into thinking Cummins has the most qualified mechanics. They don't!

* Ray,IN is probably right about the cost of the FASS UPGRADE costing $2,600 vs. $1,600 for a stock lift pump repair. That's why they call it an upgrade. ...But is it a necessary upgrade?

Ray,IN does not think so, and for him it's probably not a necessary upgrade. ...But then again I doubt he sees himself putting tens-of-thousands of miles on his coach down the road. Therefore, why spend the money! (Is that right Ray,IN?)

On the other hand, if you are capable of installing the installing the FASS fuel pump yourself, the FASS TS 95 GPH Kit ($700 including shipping) plus $150 for extra hose and other parts, then you might want to investigate doing the installation yourself. And for me, because I am putting 3,000 - 7,000 miles on my RV every year; and I plan to do so for another 5 years, it made more sense for me to upgrade to FASS and by-pass my stock Cummins Lift Pump.

FASS INSTALLATION OPTIONS:

A) As an average owner/mechanic, and if this is your first installation, I think if you budget four 6 hour-days that would be about right.

B) Or you can go to your a diesel performance shop and see if they will do it for $2,000. I think they would do it for that price, because they do Dodge trucks all the time for $1,500 (parts and labor).

C) $2,600 - $3,500 would be the price I bet an RV repair or Diesel Semi Truck Repair shop will charge.

Note: Personally, I think a "qualified and experienced FASS Installation mechanic can do an RV-FASS installation in 6-8 hours, depending on the Chassis and other variables. Therefore, I think a "fair" price would be more like $2,000, but good luck finding a mechanic to do it for this price. That's why I think your best bet is to go to a diesel performance truck shop that has room to work on your RV... and then coach them as necessary so they know it's not much different than any Dodge truck.

The purpose of upgrading to a FASS TS Lift Pump is to protect your CAPS injection pump from fuel starvation. It is NOT to replace your stock Cummins Lift Pump... even though that is what you are doing.

The goal is to get out there... Have fun... And get home safely... For the least amount of money you can spend.

Did Ray,IN make the right call? I think he did. It still cost him $1,600.

Do I think I made the right call installing the FASS TS Lift Pump in place of using the stock lift pump: I know I did. And it only cost me $850, because I did the work myself.

Does it make sense for someone to spend $2,600 on a FASS Lift Pump Upgrade? Hard to say. For me, once I know I have to spend any money I think about only doing the best; and yes... the FASS TS Lift Pump has far many more advantages over the stock lift pump.

I think anyone out there who has over 70,000 miles on your stock lift pump should be asking these questions... after you check your 3-lift pump bolts to see if they are loose!

Smitty77 12-07-2019 10:26 PM

Ray,in - I agree that the primary reason I switched to FASS, vs replacing my still non leaking and functioning Lift Pump - was to insure Positive Fuel Pressure to the CAPS. I considered it extra insurance to keep the CAPS lubricated and cooled. And yep, I use an additive to each tank of fuel, as additional insurance on lubricity (Optilube Summer Blend (I Summer + now), and I also have XPD that and Biobor JF that I'll add as I feel is appropriate.).

All that being said. Probably close to a million (Just my SWAG!) CAPS era ISC/ISL's still running in various pieces of equipment, including RV's - with Cummins OEM Lift and no positive fuel pressure... To me, I felt the CAPS was sucking fuel from a long way on DP's, usually with the fuel tank in the front - vs say probably less then 10' away for a OTR truck, or piece of Heavy Equipment or Farm gear...

Nothing to stop you in the future from adding another inline fuel pump, FASS or other.

But for now, go have some fun and learn and enjoy your new coach!
Best,
Smitty

Enjoy

Ray,IN 12-08-2019 04:55 PM

Quote:

Originally Posted by Smitty77 (Post 5067076)
Ray,in - I agree that the primary reason I switched to FASS, vs replacing my still non leaking and functioning Lift Pump - was to insure Positive Fuel Pressure to the CAPS. I considered it extra insurance to keep the CAPS lubricated and cooled. And yep, I use an additive to each tank of fuel, as additional insurance on lubricity (Optilube Summer Blend (I Summer + now), and I also have XPD that and Biobor JF that I'll add as I feel is appropriate.).

All that being said. Probably close to a million (Just my SWAG!) CAPS era ISC/ISL's still running in various pieces of equipment, including RV's - with Cummins OEM Lift and no positive fuel pressure... To me, I felt the CAPS was sucking fuel from a long way on DP's, usually with the fuel tank in the front - vs say probably less then 10' away for a OTR truck, or piece of Heavy Equipment or Farm gear...

Nothing to stop you in the future from adding another inline fuel pump, FASS or other.

But for now, go have some fun and learn and enjoy your new coach!
Best,
Smitty

Enjoy

We've owned it since April 2013, already had lots of fun, been a lot of places.


I do have a link to a FASS pump only for $599, I would retain the OEM filters.
However the new pump has gaskets designed to withstand biodiesel, it should last for the next 20 years.Hope I do.

cewarre 12-08-2019 07:26 PM

TenMillie
 
To replace the gasket you only have to remove the three screws that go through the pump manifold down into the motor assembly. However, when I replaced the gasket the stinkin' pump motor started leaking out the connector at the bottom so I had to replace the whole pump assembly anyway. This was January 2018 and the genuine Cummins pump purchased on-line cost just under $400 and I paid a great diesel mechanic friend $200 to help me install it. There are several versions of the pump out there and I opted for the newest Cummins pump P/N 5362269. BTW, it was manufactured in China.

imnprsd 12-08-2019 09:59 PM

Stock Lift Pump Vs. FASS Pump Types
 
4 Attachment(s)
A) Your stock lift pump from Cummins is a "Carter-type" lift pump that draws (sucks) fuel from the fuel tank for 30 seconds after you turn the ignition key on. If you were to measure the fuel pressure out of the lift pump you would see +15PSI out of the lift pump while it is NOT running. And then after the engine starts... and about 30 seconds later, the fuel pressure in the line will change from positive fuel pressure to negative fuel pressure when the CAPS "Low Pressure Gear Pump" is running.

So ~30-45 seconds after your engine starts, the "LOW PRESSURE GEAR PUMP" (which is a section in your CAPS pump if you review previous pictures I have post) takes over and draws (...sucks) fuel from the fuel tank all the time the engine is running. If you were to measure this vacuum pressure you would see -4 to -5PSI of vacuum pressure.

Cummins specifies the CAPS injection pump requires a minimum of -5PSI to operate efficiently.


SUGGESTION: For less than $25 you too can measure your vacuum pressure in your fuel delivery system easily by adding a vacuum gauge to the top of your fuel filter block. (Assuming you have a plug on top.)

All you need is a M10 x 1/4"NPT-Female reducer so you can mount a vacuum gauge on top of your filter block. Then all you do is remove the plug and insert the reducer and oil filled vacuum gauge on top. (See picture.) Then you can test the quality of your vacuum gear pump while the engine is running! And you can see if your engine is operating at -5PSI or not??? Here's the Amazon links:

https://www.amazon.com/Filled-Pressu...34&s=hi&sr=1-8

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

At best, I'm guessing the highest fuel pressure will be -5PSI.

...So when I measured only -4PSI (at 1800 RPM) I had to ask, was there some error in the gauge (maybe) or was it reading accurate?

NEXT QUESTIONS: Were my old 2004 fuel lines sucking air into the lines, and if so was that affecting the vacuum pressure?

Should I go to a huge expense and have those fuel delivery lines replaced as some people say fixed their fuel delivery issues? (Answer: Not if I could help it! I told myself.)

Note: My Freightliner Chassis has no access to the top of my fuel tank so in order to replace my fuel lines I would have to drop my fuel tank. (Monaco/Spartan Chassis owners do have access to the top of their tank and so they might be able to replace the fuel lines more easily. So I have heard.)

FASS TO MY RESCUE!!!

B) When you install a FASS TS (electric) Lift Pump you now have an stronger fuel pump sucking fuel from the tank; and it will supply an constant output of +15 to +18PSI of POSITIVE fuel pressure to the CAPS injection pump. Thus ensuring your CAPS pump will NEVER be starved of fuel again. And this is the main purpose of by-passing your stock lift pump.

As for any air getting sucked into the fuel delivery lines? Who cares! The FASS TS Pump is an "Air Separation Pump" that will return air and unused fuel to your fuel tank via its fuel return line. (PROBLEM SOLVED!) And all the while FASS is pumping it's also filtering the return fuel to the tank. And that will virtually eliminate your algae concerns... if you have any? I did. So once again I say: "FASS TO MY RESCUE!"

CLARIFICATION: FASS also makes just a 95 GPH Adjustable Pump, but that pump lacks many of the FASS TS Pump advantages. Namely no filtration, no air separation, and no "fuel polishing/fuel return" but it does supply positive fuel pressure just like your the TS pump does.

The installation with the Adjustible Pump is easier vs. the TS pump, but not much less expensive.

You can also find older FASS Pumps (with large filters) available on Ebay for $499/$599, but you need to check if these are the older 2018 model. And we recommend you call FASS to better understand the additional advantages of buying the newer Titanium Series "TS" Pumps launched in March-2019.

https://fassride.com/shop/product/fu...-d07-095g-kit/

Note: If you find a FASS Titanium Pump on Ebay that has "large filters" you should know this is last year's model. And there were changes FASS made in March-2019 you should call FASS to ask about so you can decide if this older pump will work for you just as well as the new Titanium Series "TS" Pump?

WHAT KEEPS FUEL FROM FLOWING THROUGH THE STOCK LIFT PUMP WHEN IT'S NOT RUNNING?

Answer: #10 in the attached schematic is a "Check Valve" that prevents fuel from flowing through the lift pump when it's not energized by the ECM.

LINK TO HOW I INSTALLED MY FASS LIFT PUMP:
https://www.irv2.com/forums/f123/cumm...mp-458337.html

imnprsd 01-07-2020 08:05 PM

If you do not upgrade to a FASS Fuel Pump...
 
1 Attachment(s)
CAPS injection pumps and systems were not designed to run on ULSD fuels.

Specifically, CAPS tolerances are very "tight" and rely on fuel lubrication and cooling for long term operation. So what can you so to avoid a Strikeout?

Strike 1: ULSD Fuel with ultra low sulfur reduces lubrication. They say bio-diesel has more lubricity than #2 Diesel, but most “hardliners” say they get less performance and less MPG. We did not find this to be the case in over 40,000 miles of driving our RV with a tow car.

Plus you never know how much bio-diesel you will get in your B5 to B20 fill-ups since you could be getting anywhere between 0%-20% bio-diesel.

Strike 2: Low Vacuum Pressure in the fuel deliver line can be caused by air leaks that reduce vacuum pressure (suction). And for 2004 and newer ISC/ISL owners, you can usually cure this by tightening those 3 lift pump bolts you are now hearing so much about!

Strike 3: Running with less than 1/4 tank of fuel in the tank. Note: The Dodge trucks call this a "Quarter Tank Problem" and it's common with their Cummins lift pumps... albeit their lift pumps run all the time and use a V44 Pump that is similar to our CAPS pump… the effects of FUEL STARVATION are the same. And when you have less fuel in your tank, your CAPS low pressure gear pump efficiency is affected by running your engine (under high demand… like climbing a grade or acceleration on a freeway on-ramp) when the fuel level in your tank drops below 1/4 tank of diesel fuel. So try to avoid this if you do NOT have a FASS fuel pump.

I also found lots of people think they got bad diesel when they fixed their engine performance problems by changing out their fuel filters. However, I think this is an early warning sign. Why? …Because your fuel delivery is falling below -5PSI of vacuum pressure to the CAPS pump and you may or may not know when this is happening.

If you get an “engine buck” then you know, but all the other times your CAPS pump is not getting enough fuel to cool itself and you are literally shortening the life of your pump.

So why does changing the fuel filters fix the problem?

...Read the attached .pdf.

imnprsd 01-16-2020 03:11 AM

"How is routing positive fuel pressure thru a leaking lift pump not going to leak?
 
3 Attachment(s)
In another thread, Rickadoo asks: ..."...how is routing positive fuel pressure thru a leaking lift pump not going to leak?"

Answer 1a: This is where the confusion starts. How?/Why? ...Most often it's not your lift pump that is leaking. It's the gasket between the lift pump manifold and the lift pump where the leak is occurring.

HOW EXPLAINED: When it comes to gasket materials, from what I have been able to glean from reading a lot about this subject from other members on this forum, the gasket material used in pre-2002 engines was not compatible with ULSD fuel. So if you have one of these older coaches then chances are your gasket has already leaked and been upgraded to a newer part number.

WHY EXPLAINED: Diesel shops like to bill for a complete lift pump and gasket replacement. And I bet you will only hear about tightening those 3-lift pump bolt on this website or some other RV forum websites. The bigger question is: Why aren't mechanics telling to first try tightening those lift pump bolts? Answer: For the same reason a plumber doesn't want to explain his craft. "...It ain't rock science, but it is a living!"

TR4 and BigLar368, who are my two best friends on this forum, because with their help I fixed my lift pump air leak in my Montana camp spot...and helped me derive the FASS TS upgrade for my 2003 Cummins ISC-350 and Freightliner Chassis is why I did NOT choose to by-pass the lift pump manifold.

REVIEW: When people say "Lift Pump" what they are talking about in general are 3 different parts:

1) The Lift Pump Manifold that has a check valve to prevent fuel from passing through the lift pump when it's not turned on.

2) The Lift Pump Gasket

3) The Lift Pump.

So, back to the question: "...how is routing positive fuel pressure thru a leaking lift pump not going to leak?

Answer #1b: Fuel does not flow through the lift pump when it's not turned on by the ECM. So no fuel will leak out.

Improvement: Since you now have a "positive" fuel delivery system, then air cannot be leaked (sucked) into the fuel lines.

Therefore, even if the Cummins fuel pump fails, so long as it does not physically leak, in theory, then you should be able to just leave it in place.

REVELATION #1: So why would anyone pay $1,500 to replace a Cummins Lift Pump when for a few more $$$ you can install a FASS TS Pump? Or you can buy the FASS TS Dodge 95GPH Kit for $700 and with $200 in other parts you can install it yourself.

REVELATOIN #2: The type of RV chassis you have will most likely determine the FASS TS Pump installation and location.

In my case, Freightliner Chassis fuel tank is not accessible from the top. So it would be a real PITA to install a FASS TS Pump in my chassis unless I allow fuel to flow through the Lift Pump Manifold.

REVELATION 3: Every will tell you that you should not route fuel through the lift pump manifold, but no one can prove this is a bad idea.

My testimonial is that I have driven 8,000 miles with +15PSI of fuel pressure flowing though the lift pump manifold and I have have absolutely no problems whatsoever. I never changed my stock lift pump or gasket. And my feeling is this: If the CAPS injection pump can pass +15 PSI of fuel RETURN pressure thru the lift pump manifold, then why can't I pass +15PSI of fuel pressure through the other side of the lift pump manifold to the #3 filter... which provides positive fuel pressure to the CAPS injection pump.

CONCLUSION:
If you can by-pass the lift pump manifold easily then do so. TR4 and BigLar368 have a different chassis than I do. ...I know BigLar368 has a Spartan chassis and an inspection door on top of his fuel tank, so that's a real plus, but I can't remember what chassis TR4 has? It's not a Freightliner that I'm sure. Maybe a Roadmaster?

Note: My Itasca-Freightliner also has a Independent Front Suspension (IFS) so there is no room by the fuel tank for a FASS up front. ...But frankly, I would not want to locate those FASS filters under the coach anyway. And it's a myth that you need to mount the FASS pump near the fuel tank.

Maybe just like it's a myth you need to by-pass the Lift Pump Manifold. I did not! All I did was remove my primary filter and install a FASS TS Pump in its place. (See picture.) And in my Freightliner Chassis it was real easy to mount the Dodge FASS Kit hardware to my chassis frame. Almost like it was meant to be there!

So I chose to mount the FASS TS Pump in the engine compartment, where I have easy access to those 2 FASS fuel filters, but I also need to point out that I have a side radiator.

So these are all factors you might want to consider before you make your plans to upgrade to a FASS Titanium Series Fuel Pump. It's a great upgrade, because it protects your CAPS injection pump from premature failure. (See previous post I have written on this subject.)

If you has a Spartan or Roadmaster Chassis like BigLar368 and TR4 and want to by-pass your lift pump manifold then follow the "pink" highlighter in the diagram below. If you have a Freightliner Chassis then follow the printed flow diagram "as described."

I hope these Revelations help you make up your mind. Upgrading to a FASS TS Pump is highly advised in my opinion and my engine has never ran better!

Jump over to this thread for more information about why and how I installed my FASS TS Pump in my Itasca "Horizon" with Freightliner Chassis:
Cummins ISC - Engine Starts But Then Quits & Why We Upgraded To FASS TS Pump!!!!

Ray,IN 02-08-2020 05:46 PM

Quote:

Originally Posted by imnprsd (Post 5026568)
Yeah, but your Lift Pump only runs for the first 30 seconds that you start your motor and then it shuts down.

But lift pump purpose is the prime the injection system so the low pressure gear pump can take over and suck fuel from the fuel tank.

The FASS fuel pump runs constantly while your engine is running... that's the point!

The FASS TS fuel pump has two additional filters... and recycles fuel to your tank which removes. algae and other contaminants.... and that's the point

Just in case you don't have this bookmarked already, this is very interesting: https://quickserve.cummins.com/servi...0/05/iscts.htm

TR4 02-08-2020 07:16 PM

Quote:

Originally Posted by Ray,IN (Post 5140694)
Just in case you don't have this bookmarked already, this is very interesting: https://quickserve.cummins.com/servi...0/05/iscts.htm

Great find, thanks for posting! Interesting, it says to warn customers not to pre-fill fuel filters.

Bill

Mile Marker 42 12-16-2020 10:11 PM

Quote:

Strike 3: Running with less than 1/4 tank of fuel in the tank. Note: The Dodge trucks call this a "Quarter Tank Problem" and it's common with their Cummins lift pumps... albeit their lift pumps run all the time and use a V44 Pump that is similar to our CAPS pump… the effects of FUEL STARVATION are the same. And when you have less fuel in your tank, your CAPS low pressure gear pump efficiency is affected by running your engine (under high demand… like climbing a grade or acceleration on a freeway on-ramp) when the fuel level in your tank drops below 1/4 tank of diesel fuel. So try to avoid this if you do NOT have a FASS fuel pump.
Interesting info. Not sure if you are following this thread: https://www.irv2.com/forums/f115/dea...516487-23.html but he originally 2 weeks ago with a leaky lift pump climbed a 10% grade in CO with a 1/4 tank of fuel and his engine shut down. He is still in Denver trying to fix it as of today. Very sad story. When I first read it, I said to myself, "who climbs a 10% grade in 20 degree weather on a 1/4 tank of fuel"? Well this guy did. So ever since then, I have been reading as many posts as I can on this subject and 1 of them brought me to yours. Turns out that I too have the CAPS system with the lift pump mounted directly above the starter. No accessibility from the top really. Thank god it isn't leaking and I don't ever run on a 1/4 tank of fuel for very long. Thx, just wanted to share.

seaquest7 08-28-2021 12:52 PM

Quote:

Originally Posted by imnprsd (Post 5068371)
A) Your stock lift pump from Cummins is a "Carter-type" lift pump that draws (sucks) fuel from the fuel tank for 30 seconds after you turn the ignition key on. If you were to measure the fuel pressure out of the lift pump you would see +15PSI out of the lift pump while it is NOT running. And then after the engine starts... and about 30 seconds later, the fuel pressure in the line will change from positive fuel pressure to negative fuel pressure when the CAPS "Low Pressure Gear Pump" is running.

So ~30-45 seconds after your engine starts, the "LOW PRESSURE GEAR PUMP" (which is a section in your CAPS pump if you review previous pictures I have post) takes over and draws (...sucks) fuel from the fuel tank all the time the engine is running. If you were to measure this vacuum pressure you would see -4 to -5PSI of vacuum pressure.

Cummins specifies the CAPS injection pump requires a minimum of -5PSI to operate efficiently.


SUGGESTION: For less than $25 you too can measure your vacuum pressure in your fuel delivery system easily by adding a vacuum gauge to the top of your fuel filter block. (Assuming you have a plug on top.)

All you need is a M10 x 1/4"NPT-Female reducer so you can mount a vacuum gauge on top of your filter block. Then all you do is remove the plug and insert the reducer and oil filled vacuum gauge on top. (See picture.) Then you can test the quality of your vacuum gear pump while the engine is running! And you can see if your engine is operating at -5PSI or not??? Here's the Amazon links:

https://www.amazon.com/Filled-Pressu...34&s=hi&sr=1-8

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

At best, I'm guessing the highest fuel pressure will be -5PSI.

...So when I measured only -4PSI (at 1800 RPM) I had to ask, was there some error in the gauge (maybe) or was it reading accurate?

NEXT QUESTIONS: Were my old 2004 fuel lines sucking air into the lines, and if so was that affecting the vacuum pressure?

Should I go to a huge expense and have those fuel delivery lines replaced as some people say fixed their fuel delivery issues? (Answer: Not if I could help it! I told myself.)

Note: My Freightliner Chassis has no access to the top of my fuel tank so in order to replace my fuel lines I would have to drop my fuel tank. (Monaco/Spartan Chassis owners do have access to the top of their tank and so they might be able to replace the fuel lines more easily. So I have heard.)

FASS TO MY RESCUE!!!

B) When you install a FASS TS (electric) Lift Pump you now have an stronger fuel pump sucking fuel from the tank; and it will supply an constant output of +15 to +18PSI of POSITIVE fuel pressure to the CAPS injection pump. Thus ensuring your CAPS pump will NEVER be starved of fuel again. And this is the main purpose of by-passing your stock lift pump.

As for any air getting sucked into the fuel delivery lines? Who cares! The FASS TS Pump is an "Air Separation Pump" that will return air and unused fuel to your fuel tank via its fuel return line. (PROBLEM SOLVED!) And all the while FASS is pumping it's also filtering the return fuel to the tank. And that will virtually eliminate your algae concerns... if you have any? I did. So once again I say: "FASS TO MY RESCUE!"

CLARIFICATION: FASS also makes just a 95 GPH Adjustable Pump, but that pump lacks many of the FASS TS Pump advantages. Namely no filtration, no air separation, and no "fuel polishing/fuel return" but it does supply positive fuel pressure just like your the TS pump does.

The installation with the Adjustible Pump is easier vs. the TS pump, but not much less expensive.

You can also find older FASS Pumps (with large filters) available on Ebay for $499/$599, but you need to check if these are the older 2018 model. And we recommend you call FASS to better understand the additional advantages of buying the newer Titanium Series "TS" Pumps launched in March-2019.

https://fassride.com/shop/product/fu...-d07-095g-kit/

Note: If you find a FASS Titanium Pump on Ebay that has "large filters" you should know this is last year's model. And there were changes FASS made in March-2019 you should call FASS to ask about so you can decide if this older pump will work for you just as well as the new Titanium Series "TS" Pump?

WHAT KEEPS FUEL FROM FLOWING THROUGH THE STOCK LIFT PUMP WHEN IT'S NOT RUNNING?

Answer: #10 in the attached schematic is a "Check Valve" that prevents fuel from flowing through the lift pump when it's not energized by the ECM.

LINK TO HOW I INSTALLED MY FASS LIFT PUMP:
https://www.irv2.com/forums/f123/cum...mp-458337.html

I know this is an old thread but I'm hoping someone can answer a related question.
I have a 2001 American Tradition, Spartan chassis, with a 8.3 ISC Cummins. I'm stuck at a campground because during my pre-trip routine of snugging up the three fuel transfer pump bolts, I stripped one hole in the bottom electric pump housing. I purchased a new pump assembly but instead of replacing the whole assembly and chancing breaking one of the stiff lines connected to it, I'd like to just replace the bottom half that the three bolts screw into. It's hard to tell if there is enough clearance to remove the bottom electric motor/housing once unbolted, but it looks like there may be. My question is will I get a steady stream of fuel from the supply side hole (fuel tank) that gets exposed once the electric motor housing is removed? I'm hoping it would it just be whatever is left in the fuel line or filters but I don't really know. All hoses and plugs currently connected to the pump manifold will remain intact. I'm placing a container to catch any fuel that leaks but my container will only hold about 2 gallons and I don't now how long it will take me to get the new one in place and bolted up. I didn't see any fuel cut off option but I'm surprised there isn't one. Sharing of any thoughts or experience would be greatly appreciated.
I would normally just have a shop do the work but around here (Cave City Kentucky) all shops that can do the work have told me they're book solid into late next week. I had to drive my toad to the Cummins shop in Nashville TN to get the pump (a very long 184 RT) so the local shops could get on t once they had an opening.
I would have gone the FASS way instead if I had more time to find someone to install it and get the parts delivered in time. Replacing the original with the newer "Improved" version was all I could manage to get installed quickly.

jacwjames 08-28-2021 04:13 PM

You will loose a little fuel but not much since the fuel tank elevation is lower then the lift pump itself.



I was having trouble with my fuel pump starting to leak so I just bite the bullet and installed a FASS pump and bypassed the old lift pump. I had to disconnect the fuel lines in & out to put a union between them and caps on the lift pump. Lost very little fuel.

You should have enough room to pull the lower section off, make sure the hole patterns are the same, if you luck the new pump will have a gasket that matches the old.

shootist 08-28-2021 07:18 PM

Did you already separate the new pump motor from the pump? I think at worst you will have to pull the starter. Reaching the plug from the bottom you depress the center tab. You can't see it so find the part that moves on the plug and push it down. It will be on the top side. The wiring goes to the ecm so don't have it connected when you drop the motor. Also raise the back up and leave the nose down for lessening the fuel flow if you open the lines. And disconnect the batteries house and chassis if you go to drop the starter. Lastly if for any reason you get stuck with it doa you have to air it up with an external compressor to get under it.

seaquest7 08-28-2021 07:34 PM

Quote:

Originally Posted by jacwjames (Post 5892251)
You will loose a little fuel but not much since the fuel tank elevation is lower then the lift pump itself.



I was having trouble with my fuel pump starting to leak so I just bite the bullet and installed a FASS pump and bypassed the old lift pump. I had to disconnect the fuel lines in & out to put a union between them and caps on the lift pump. Lost very little fuel.

You should have enough room to pull the lower section off, make sure the hole patterns are the same, if you luck the new pump will have a gasket that matches the old.

Thanks for the quick reply. This is the answer I was hoping for.

Per the service tech at Nashville Cummins, the old pattern is the same. He said the upgrade was the electrical motor and the rubber gasket. He said the gasket was upgraded to work with the ultra low sulfur fuel and the electric motor was beefed up due to many past failures. He said the fuel housing/manifold that the electrical pump mounts to hasn't been changed since its original design. Looking at them the only difference I can see is the three bolts that can loosen up now have star head and the bolt it self has a course thread and a slight triangular shape (not round) and is tapered for about a 1/4 inch at the end. Im not familiar with this style bolt but it seems as though it may be some sort of self locking bolt. My new concern is that if this is the case I may have just defeated the fix for the bolts loosening up. I'll put a drop of thread lock on them before using them just t be sure.
Again, thanks for the help.

radar 08-28-2021 07:42 PM

Cummins keeps them in stock and if I remember correctly they come with everything you need including o-rings etc. Back in 2007 or maybe 2008 we had to change ours. We.changed it in a flying J somewhere around Palm Springs. I thought I would change it from below but I ended up holding the flashlight while wifey changed it from the bedroom access hole. Bit of a stretch though. Prime (with the key) many times before turning it over.

Good luck.

seaquest7 08-28-2021 07:50 PM

Quote:

Originally Posted by shootist (Post 5892422)
Did you already separate the new pump motor from the pump? I think at worst you will have to pull the starter. Reaching the plug from the bottom you depress the center tab. You can't see it so find the part that moves on the plug and push it down. It will be on the top side. The wiring goes to the ecm so don't have it connected when you drop the motor. Also raise the back up and leave the nose down for lessening the fuel flow if you open the lines. And disconnect the batteries house and chassis if you go to drop the starter. Lastly if for any reason you get stuck with it doa you have to air it up with an external compressor to get under it.

Hi and thanks for the response.
I haven't disconnected the old pump motor yet. I can see the electrical plug (a little) and I can get that disconnected. Hopefully I won't have to remove any other parts. Good suggestion on lowering the front to help lessen the fuel flow and of course killing all power before messing with the starter.
I've seen a screwdriver burst in half coming across a hot battery cable to ground. I don't want those surprises :nonono:
Thanks for the suggestions and quick response.

seaquest7 08-28-2021 07:54 PM

Quote:

Originally Posted by radar (Post 5892460)
Cummins keeps them in stock and if I remember correctly they come with everything you need including o-rings etc. Back in 2007 or maybe 2008 we had to change ours. We.changed it in a flying J somewhere around Palm Springs. I thought I would change it from below but I ended up holding the flashlight while wifey changed it from the bedroom access hole. Bit of a stretch though. Prime (with the key) many times before turning it over.

Good luck.

Thanks for the info and story. I'd like to be the one that holds the flashlight for a change :)

radar 08-28-2021 08:16 PM

Quote:

Originally Posted by seaquest7 (Post 5892466)
Thanks for the info and story. I'd like to be the one that holds the flashlight for a change :)

Yes, the advantages of being married to a retired soldier/technician. She always wants to hold the wrench. :).

dale1 10-31-2021 07:10 AM

sequest7. I'm having similar problems. would like to know the outcome? thank you, dale

jacwjames 10-31-2021 07:41 AM

dale1
You should sent a PM to the person.



Just click on the name in the post and a drop down menu will pop up with one option "Send PM", click on it an it will bring up a text box to send message.

CountryB 11-02-2021 08:42 AM

1 Attachment(s)
Quote:

Originally Posted by cewarre (Post 4072422)

I spoke with Carl at Capital Volvo, 1-800-247-5673 and he said he still has 370 of the aftermarket gaskets in stock for the Cummins lift pumps and gets calls quite often. They are still $6.71 each and he is shipping me two via UPS. He said the aftermarket gaskets reference to Cummins part numbers 3964385 and 4935004.

Did you confirm that the part numbers for the gasket is correct? The numbers you listed don't match what others are posting (i.e. gasket is 4928511).

Also what engines, if any, (besides the ISC) use this same transfer pump?

Rcook1956 11-22-2021 02:59 AM

Convert to a FASS pump and never have a problem again. Look them up on internet but best to give them a call. I converted mine to a 165 gph pump in a few hours.

cbr46 04-05-2022 08:31 AM

Quote:

Originally Posted by CountryB (Post 5972095)
Did you confirm that the part numbers for the gasket is correct? The numbers you listed don't match what others are posting (i.e. gasket is 4928511).

Also what engines, if any, (besides the ISC) use this same transfer pump?

On my 2003 ISC (2002 motor?) the gasket is 3944382, and doesn't look anything like the gasket in the above thumbnail.

- bob

BMU-Scotty 05-09-2022 12:24 AM

Cummins OEM Lift Pump - Get Rid Of It!
 
I think all RVs came with an earlier model engine. I.e., a 2003RV probably has a 2002 Cummins engine.

As for the Cummins OEM (Carter) Lift Pump and fuel delivery system, which sucks, literally Cummins does not like talking about their lift pump very much or how it works; or if there is even a check valve installed as shown in the diagram. It's all a big mystery; and getting technical support is hard... from anyone.

This is because today's technical support team(s) barely understands how a CAPS-1 or CAPS-2 (aka HPCR used in 2005-6 RV) fuel system works. However, you can't blame them since they stopped delivering these systems back in 2003/4 and none of these guys have ever replaced a CAPS pump and those techs who have probably forgot how these things work. ...For that you need to talk to a Farmer who is still running ISC motors made back then.

On the positive side, I will say the Cummins telephone technical support is very helpful, and far more likely to help you vs. the customer service you will get by taking your RV to a Cummins Stealer.

As to the gasket part number and type: From 2001-2004 each RV sold with a Cummins ISC/ISL OEM lift pump came with it's own gasket part number; and I think this is because, IMO, as these lift pump gaskets continued to fail due to USLD fuel changes; so Cummins kept making new gasket materials, which explains all the different part numbers, even though the OEM lift pump looks the same.

You see, the older gasket with a screen was supposed to be the fist line of defense against algae, and then the single 20u filter would do the rest.

But when the injection pump accumulator started to fail due to algae contamination, they started coming out with 2-filter systems (an upgrade) and some RV manufactures modified the fuel delivery system and shipped their coaches with a 20u-primary and a 10-u secondary filter.

Note: With a Cummins suction fuel delivery system you never want to install less than a 10-micron fuel filter. However, after you convert to a FASS or AirDog you can run 2 filters. I recommend the first filter being 20u or larger (not smaller) and the second filter can be as low a 3u. I also prefer FASS because I like their high rate of fuel flow back to the fuel tank, which means you a lot of fuel 100GPH will be filtered as you drive. And that will take care of most algae concerns over time. They call it "fuel polishing." Whatever.

Moving on: Winnebago was too cheap to install 2 filters so most of their RVs only came from the factory with 1-10u filter; leaving owners to upgrade to 2-filters, which was better after they started have performance problems, commonly due to algae. (This why you need to use a biocide when you store your RV for more than 3 months.)

Moving on: The CAPS gear-driven fuel pump (not to be confused with the 30-second lift pump, which is used to prime the engine for starting purposes only) is based on -15psi of suction. And when that lift pump gasket starts to leak/suck air, usually because those 3-lift pump bolts are loose, or the gasket material is disolved by modern day USLD fuel, what happens is that the suction is lost... and that's the root cause of all these CAPS injection pumps failing. I.e., the fuel provide the cooling and when you starve your CAPS injection pump of fuel, it heats up, and all sorts of bad things follow.

Example: You may think you lost a suppressor diode, but most likely the real problem is propagated by not enough fuel. And the root cause is this: Your OEM gear pump (-15PSI) is not able to overcome pressure decreases (climbing hills or having less than 1/4 tank of fuel to begin with); and on top of all this, your new ULSD fuel does not contain enough Sulphur in it, like it used to, to lubricantes the CAPS injection pump.

...Then the stator starts working overtime, and the suppressor diode can't block the transients shock which protect the ECM.

...Then you break down, get your RV towed, your trip is ruined, and the Cummins Stealer Shop wants big money to replace the ECM, or worse, both the ECM and the CAPS injection pump ($8,000+). It's a racket. And all because you didn't what you now know!

So what can you do? Answer: Install a FASS or Airdog, and which type may depend on which method is easiest and cheapest to install for your type of RV chassis. I.e., it all comes down to the best/easiest/cheapest way to run a new electric lift pump fuel return line.

Note: Bothe FASS and Airdog will turn your OEM (suction type) fuel delivery system in to a positive (+15PSI) delivery system.

Personally, I have no preference. FASS vs. Airdog, but the easiest installation will mostly depend on it you have easy access to route a new fuel pump return line to your tank. If so, I would go with FASS. If not, I would go with AirDog.

To recap: If you don't have a FASS or Airdog. And I would say, you should get one ASAP if you plan on driving your RV a lot, but cause your chance of experiencing a CAPS failure increases over time; and by time I mean 50K+ miles. I.e., if your rig is at 50K miles or more, and who's isn't these days, and you have not installed a FASS or Airdog, then you really should think about it.

====

Regarding the lift pump "manifold." This thing is cast pot metal. And the fuel line-in ports are separate from the CAPS fuel return that sends fuel back to the gas tank. So when you talk about the air entering the system you are only dealing with the gasket that goes between the fuel pump manifold and the OEM lift pump that runs for 30 seconds. And the fuel return ports inside the Lift Pump Manifold are totally separate and have nothing to do with that lift pump gasket leaking air or leaking fuel on the ground.

Remember: The general concern is that all fuel coming from the fuel tank is being sucked by the CAPS gear driven fuel pump; and that 30-second lift pump is turned off after the engine starts. However, fuel is still passing through the fuel-in ports of that lift pump manifold. So even though the 30-second lift pump is not a factor after the engine starts, that lift pump gasket can let air get sucked-in.

Therefore, if you are experiencing "issues" with your engine performance, or if on cold days your engine starts and then stops; or if your engine starts and then stops when you lave less than 1/4 of fuel... Step-1 is to tighten those 3 lift pump bolts and see if that fixes your problem.

Step-2, which I highly recommend, is to install a FASS or Airdog -- and preferably bypass the lift pump manifold fuel-in port as much as you can.

To accomplish this, some people plug those lift pump "manifold" ports, while other owners just remove the primary filter and put a FASS pump in it's place and run 3 filters.

IMO, there is no need to have 3 filters as show in the diagrams above. In fact, the more you can do to simplify your fuel delivery system the better. And this included bypassing your lift pump all together.

Once you provide "+" fuel pressure to your CAPS injection pump, by installing a FASS or Airdog electric lift pump, you know you will get sufficient fuel flow and marginal cooling.

That said, I also recommend you always supplement your diesel fuel tank with a diesel additive at each or every other fill up, because your CAPS injection pump needs as much lubrication as it can get -- that is if you expect it to last forever, which it will do, if you take care if your fuel. And if you don't install a FASS or Airdog, then you maybe driving on "borrowed time."

dons2346 05-09-2022 09:16 PM

"...Then the stator starts working overtime, and the suppressor diode can't block the transients shock which protect the ECM."

Scotty, you are the first to mention the diode, congratulations..


I actually had a diode go south on me and the Cummins stealer was talking lift pump and an array of other parts. Luckily I have a friend that is a certified Cummins guy and after giving him the codes, he said suppressor diode which was a $127 part. Much better than the big buck pumps,

cbr46 05-10-2022 07:13 AM

Quote:

Originally Posted by BMU-Scotty (Post 6174895)
I think all RVs came with an earlier model engine. I.e., a 2003RV probably has a 2002 Cummins engine.

As for the Cummins OEM (Carter) Lift Pump and fuel delivery system, which sucks, . . . .

That is and EXCELLENT "prim-er"!

I didn't know about the suppressor diode. My main concern was sucking air into the fuel from a leaky lift pump. Now I'm curious how the suppressor diode works . . . .

In my case the gasket holes wouldn't even line up with the holes in the lift pump. Yes, probably a 2002 engine. Now that the leak was much worse I ended up bypassing the lift pump.

And yes, I installed a FASS pump for many of the above reasons. :dance:

- bob

mydogmax 05-18-2022 02:50 PM

So if you have a model newer then a 2004, your pump should be ok?


Where is the assist pump normally mounted?

cbr46 05-19-2022 07:07 AM

Quote:

Originally Posted by mydogmax (Post 6185889)
So if you have a model newer then a 2004, your pump should be ok?

Where is the assist pump normally mounted?

After 2004 Cummins switched from the CAPS to HPCR fuel injection pumps with the same lift pump to prime it. Fuel is still sucked by a multi-thousand dollar pump from the main tank 20 feet away, not a great design. Maybe it's the fear of failure like the CAPS pump I don't know.

The "assist" pump (FASS or Air Dog) is mounted wherever the installer can or wants. Some like it near the source (fuel tank) so it's mostly pushing fuel, some like it in the easiest mounting location . . . . like the primary filter location (replacing that filter). The FASS has 2 filters mounted to it - a 140 um primary with a 2 um secondary filter. This makes the ISC 10 um secondary filter rather useless but most everyone leaves it in place.

HIGHLY RECOMMEND installing a fuel gauge with sensor at the secondary filter so the driver can see pressure falling as the FASS (or Air Dog) filter becomes clogged with particulate or water. The FASS filter does NOT have a water drain. Also HIGHLY RECOMMEND using a fuel treatment such as Biobor JF to add lubricity to the ULSD (Ultra Low Sulfur Diesel) fuel during fillups . . . and it kills algae that may develop if the coach has infrequent use. A few pennies spent on fuel can save thousands if the CAPS or HPCR pump fails (not to mention towing, overnight costs, transportation home & back, downtime, etc).

- bob


All times are GMT -6. The time now is 08:23 PM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2022, vBulletin Solutions, Inc.