Community Forums

JPG010783 · 10-13-2022, 02:41 PM

Here's my story:

On Sunday, while driving through the mountains in Colorado, within about a 30-minute time period "Engine Fault Stop" light came on 3 or 4 times. It would briefly beep and stay lit for only a second or two, then would disappear. Other than that, nothing crazy would happen to the operation of the motorhome.

I did notice throughout the drive that the shifting seemed a bit off (i.e. sometimes rough and sometimes delayed). I also noticed that at times my power / acceleration seemed to be lacking. However, I was not running any hotter than typical when climbing steep grades, my transmission fuel temp was okay and my oil pressure was also good.

About an hour later as I was approaching a junction and was slowing down and speeding up with traffic, the light (and audible alarm) seemed to come on each time that I pressed the accelerator. I then came to a stop at the junction, pressed the accelerator and took a right. I had very little power and felt a rough shift, I gained a little speed, but again noticed that when I pressed the accelerator the the light would come on and the alarm would sound. As I was pressing and letting off of the accelerator, the light then came on and stayed on. The engine then stalled.

Thankfully I was able to safely coast to a pullout on the side of the highway, but was not been able to get the engine to start and had to get it towed to McCandless in Colorado Springs.

The shop is wanting to replace the fuel pressure sensor, but thinks the CAPS pump is going to need to be replaced... I find it odd that both parts would go out at the same time, but am following their guidance at this point.

Long story short, my fear is the CAPS pumps is going to need to be replaced. They are quoting $5,700 for the pump and $4,000 in labor (20 hours @ $205 / hour). For one, 20 hours seems like a lot of time to replace the pump, but my main question to this forum is does anyone know where I can source a new / rebuilt pump?

My wife, daughter and I live in our RV full-time and cannot stay in it while it's at their shop, so we're displaced until we can get it running again.

Also, to add a bit more color to my story, last summer I replaced the fuel lift pump and the surge suppressor. I haven't had any engine issues since then, until of course on Sunday when it died on me.

I have a ScanGauge D and it is showing the following two error codes:
#1 ID 106 FM 0 CNT 0
#2 ID 94 FM 10 CNT 0

Here are the details of my rig:
2001 Newmar Mountain Aire
Cummins ISC 8.3 Liter CM 554 350 HP
Allison MD3000MH 6 speed
Spartan Mountain Master Chassis, MM2242

Thanks in advance for the help!

shootist · 10-13-2022, 05:08 PM

Can you find an independent shop? How many miles on the coach?

Surf Fisher · 10-13-2022, 05:40 PM

CAPS injection fuel pumps are expensive, and they are located in a difficult area of the engine to replace.

A lot of my Monaco friends are replacing the stock fuel lift pump with a FASS pump as the stock lift pump only works for starting the engine then it's up to the CAPS pump to draw fuel from the tank. Whereas the FASS fuel pump is working all the time reducing the strain put on the CAPS system.

Can't help you with shops as I am not familiar with the area.

jacwjames · 10-13-2022, 07:25 PM

I suggest you create an account on the Cummins Quickserve site, once you create an account you register your engine by SN. From there you can look up the part number for the parts you are looking for. From there you can search the internet.

You can also search for your fault codes and it will provide trouble shooting info. It might give you enough information to quiz your shop as to what they are doing.

The prime reason for the CAPS pump to fail is the transfer pump leaking while running and then sucking air when it shuts off while the engine runs. I would be looking at that as the root cause of failure. If the transfer pump has been leaking and is not replaced you will fail another CAPS pump.

AFChap · 10-14-2022, 07:51 AM

My fuel pressure sensor issue last spring turned out to be clogged fuel line between the filters & the pump. Along the way, they broke the sensor off in the fuel pump head so had to replace both parts in addition to cleaning out the fuel line .

JPG010783 · 10-14-2022, 08:55 AM

Quote:

Originally Posted by shootist

Can you find an independent shop? How many miles on the coach?

Potentially, but that means I'd have to get it towed again (which obviously isn't cheap)... I took it to this shop because it was the nearest Cummins affiliated shop and I am hesitant to take it to a shop that isn't Cummins certified.

It has about 108,000 miles on it.

JPG010783 · 10-14-2022, 09:04 AM

Quote:

Originally Posted by Surf Fisher

CAPS injection fuel pumps are expensive, and they are located in a difficult area of the engine to replace.

A lot of my Monaco friends are replacing the stock fuel lift pump with a FASS pump as the stock lift pump only works for starting the engine then it's up to the CAPS pump to draw fuel from the tank. Whereas the FASS fuel pump is working all the time reducing the strain put on the CAPS system.

Can't help you with shops as I am not familiar with the area.

Thanks for the note... I've done a bit of reading on the FASS pumps, but I am hesitant to add after-market parts since I am not a mechanic and don't want to create more problems for myself down the road if / when the FASS has issues with. Another hurdle I can foresee is finding someone qualified and knowledgeable enough to install it correctly, because it appears that if it is not installed correctly, then it can cause way more harm than good. Also, my understanding is that a Cummins dealer won't touch a FASS pump, so if I have issues with it, or anything within the vicinity of it, then they'll throw their hands up and I'll be left needing to find someone who is familiar with them -- which again, these qualified folks seem to be few and far between.

As far as replacing the current CAPS pump, again I am not a mechanic, but the pump is located at the back of the engine immediately at the opening of the engine compartment -- so access doesn't appear to be difficult. Now I don't know what it entails to remove and replace the pump, if there are nuts and bolts in hard to reach places, etc., but the immediate access is actually pretty easy (IMO).

JPG010783 · 10-14-2022, 09:08 AM

Quote:

Originally Posted by jacwjames

I suggest you create an account on the Cummins Quickserve site, once you create an account you register your engine by SN. From there you can look up the part number for the parts you are looking for. From there you can search the internet.

You can also search for your fault codes and it will provide trouble shooting info. It might give you enough information to quiz your shop as to what they are doing.

The prime reason for the CAPS pump to fail is the transfer pump leaking while running and then sucking air when it shuts off while the engine runs. I would be looking at that as the root cause of failure. If the transfer pump has been leaking and is not replaced you will fail another CAPS pump.

Thanks for the tips!

As far as the transfer pump, I actually had that replaced at a Cummins shop last summer. So while it is possible that it is leaking, I doubt it. I also have not noticed any fuel leaking on the ground... would it make it to the ground? Or how would you recommend that I confirm if the pump is leaking or not?

JPG010783 · 10-14-2022, 09:14 AM

Quote:

Originally Posted by AFChap

My fuel pressure sensor issue last spring turned out to be clogged fuel line between the filters & the pump. Along the way, they broke the sensor off in the fuel pump head so had to replace both parts in addition to cleaning out the fuel line .

Oh geez, sounds about right where the issue is an easy fix, but more problems were caused in the process!

Harb2500 · 10-14-2022, 01:50 PM

I had to have the CAPS Injector pump replaced in February of this year at a Cummins repair center in Cincinnati. The price was the same as you were quoted. I had them replace the radiator, the water pump and thermostat while they had it all apart. The total was a small fortune but the old girl is running sound.

It may be a little cheaper if you have a side radiator. One of the big cost and what makes the hours go up is the gear that drives the pump has to be pulled before the pump can be removed. The pump is on one side of the mounting plate and the gear is on the other. There is a lot of stuff in the way that has to be removed.

All CAPS Injector pumps are re-manufactured with no user replaceable parts. The distribution manifold was leaking on mine but I had to have the whole pump replaced instead of the manifold. 2016 was the last year supposedly you could buy the individual parts for the injector pump.

Ray,IN · 10-14-2022, 07:22 PM

July 2021 the fuel distribution module failed on my main pump. Cummins Great Plains replaced it after several days of diagnosing the problem. Then had to wait 5 days for a rebuilt one to arrive.
Normally they had replacement parts next day, but the pandemic caused the long delay.
They gave me a choice, a rebuilt main pump $10,000 or just the rebuilt fuel distribution module for $5,000.
Oddly, the fuel distribution module is 12V, I thought it was mechanical drive. That required replacing the transient voltage suppressor.

funjnt · 10-15-2022, 04:52 AM

I haven't had mine go bad but have done the research when that day hopefully never arises. I found this online and they work on and repair injection pumps.

https://bkdiesel.com/i-30499453-8-3l...fuel-pump.html

Hope this is a help.

JPG010783 · 10-15-2022, 07:08 AM

Quote:

Originally Posted by Harb2500

I had to have the CAPS Injector pump replaced in February of this year at a Cummins repair center in Cincinnati. The price was the same as you were quoted. I had them replace the radiator, the water pump and thermostat while they had it all apart. The total was a small fortune but the old girl is running sound.

It may be a little cheaper if you have a side radiator. One of the big cost and what makes the hours go up is the gear that drives the pump has to be pulled before the pump can be removed. The pump is on one side of the mounting plate and the gear is on the other. There is a lot of stuff in the way that has to be removed.

All CAPS Injector pumps are re-manufactured with no user replaceable parts. The distribution manifold was leaking on mine but I had to have the whole pump replaced instead of the manifold. 2016 was the last year supposedly you could buy the individual parts for the injector pump.

Thanks for the info! Glad to hear your problem is resolved as well.

JPG010783 · 10-15-2022, 07:11 AM

Quote:

Originally Posted by funjnt

I haven't had mine go bad but have done the research when that day hopefully never arises. I found this online and they work on and repair injection pumps.

https://bkdiesel.com/i-30499453-8-3l...fuel-pump.html

Hope this is a help.

Thanks! And yes, I hope you are able to avoid this issue!