Warning light

[Jeff753]

Started this morning and warmed up. Drove to new site about 3 miles away. Went to start again to move into site and warning light came on. Seemed hard to start too (cranked longer). I'm due for fuel filters (12 months).
Fluids all checked okay.
Is there a trick to draining the water bowl on the primary filter or just drain some fuel? Don't want any air in the system.

Jeff
2001 Dynasty cummins 8.3 350 ISC

[bobrw9]

Changing the filter(s) is the first and easiest thing that may work.

Otherwise it may very well the liftpump.

I have a LSI 400 Cummins and the lift pump has been replaced twice at about 18000 mile each.


Bobrw9

And finely too those dear paranoid people who check behind shower curtains for murderers; I'm curious, if you find one, what's your plan?

[Jeff753]

Lift pump is a year old:(

[koda59]

I have the ISL 400. My book says to open the fuel filler to release any pressure, open the water separator valve and drain . Might get some fuel out also. Close the fuel access cap.

[Jeff753]

Thank you for that info. I went in and turned the key to verify the warning light was still there and it was gone! Can't complain I guess.

I then followed your info and opened the fuel tank, drained the plastic bowl on the bottom of the (primary filter?) and closed the tank.

One thing I am not sure of (well many but this one is relevant I have two fuel filters. One has a plastic bowl which I thought was the water separator. The other filter says Cummins fuel/water Separator 3800394 and has the electrical connection (I presume for the water in fuel light) and this plastic drain port on the bottom (see pic below). Should it be drained periodically or not. I presume this is the secondary filter? Which would alarm if water passed the first filter with the plastic bowl on the bottom?



Jeff
2001 Dynasty Regent tag axle
Cummins 350 8.3 ISC

[Jeff753]

Originally Posted by Jeff753

Thank you for that info. I went in and turned the key to verify the warning light was still there and it was gone! Can't complain I guess.

I then followed your info and opened the fuel tank, drained the plastic bowl on the bottom of the (primary filter?) and closed the tank.

One thing I am not sure of (well many but this one is relevant I have two fuel filters. One has a plastic bowl which I thought was the water separator. The other filter says Cummins fuel/water Separator 3800394 and has the electrical connection (I presume for the water in fuel light) and this plastic drain port on the bottom (see pic below). Should it be drained periodically or not. I presume this is the secondary filter? Which would alarm if water passed the first filter with the plastic bowl on the bottom?



Jeff
2001 Dynasty Regent tag axle
Cummins 350 8.3 ISC

Forgot pic


Jeff
2001 Dynasty Regent tag axle
Cummins 350 8.3 ISC

[CampingCajun]

That is the drain.

[bobrw9]

Jeff,
When you have two fuel filters installed, they will be called the primary filter and the secondary filter.
The primary filter is between the tank and the lift pump.
It’s job is to stop the big debris and water.
The knob is to drain the water and the electrical connection is to turn on the (water in fuel) warning light.

The secondary filter is after lift pump and before the injection pump.
Its job is protect the injection pump.

When I purchased my coach it had wrong filters in both positions.
Make a note, you can never trust anyone about anything pertaining to maintenance of you coach.

The correct filters for my LSI 400:
Primary filter is FS 1065. 10 micron and 98.7% efficient.
Secondary filter is FF 5636. 2 micron and 98.7% efficient.

Search (fuel filters) and read everything you can find from Gary Spires (spike 45), retired Cummins filtration SR. Field Engineer.
Whatever spike 45 says you can take to the bank.
All the rest is questionable at best and wrongheaded sometimes.

bobrw9

I don’t like to make plans for the day because the word “premeditated” get’s thrown around in court too much.

[Jeff753]

So I have two filters. One has a plastic bowl on the bottom to drain. The other has a drain port and electrical connection (see in prior post).
Which one should be the primary?
My manual only shows the one with a drain port and electrical connection and I think it list a different part number than the one that is on my ISC.
Any 2001 350 8.3 ISC owners care to list their part numbers.

[bobrw9]

(Witch one should be the primary filter?) is the wrong question.
The primary filter is the filter between the tank and the lift pump.
You will have to follow the fuel lines and discover where they lead you.
It sounds like both of your filters are designed to be primary filters.
As I said before, some low rent wrench has most likely put whatever filter he had on the shelf on your coach.
You have to follow the fuel lines to make certain witch filter is primary and witch is secondary.
Then you must decide witch filter’s you wont to use.
There are many to choose from BUT Cummins has strong opinions about witch filters should be used on your engine.
Read what Spike 45 has to teach you.
Call Cummins and ask them.
When I was a lot younger I followed the rule (TRUST BUT VERIFY).
With this last couple of generations coming to the work place I have had to modify the rule.
DO NOT TRUST ANYONE AND VERIFY EVERYTHING.

[Jeff753]

I'm still very interested in fuel filter numbers for any circa 2001 Dynastys using the 350 ISC engine.

Looks like a couple years ago, when I got this coach, they put on the wrong filter in the primary position (roadside??). They used a Fleetguard FS1242 My manual says Monaco used a Racor S3201T which crosses to a FS19738 filter. They FS19738 is a half inch taller and only .1" smaller diameter than the wrong filter. It's actually a volume of 304.65 vs the wrong one with a volume of 299.37
Would this wrong, smaller filter be enough difference as to cause performance problems? My tag Dynasty 350ISC feels a bit underpowered. It is very heavy so maybe that's just the nature of the beast? They did offer a 400 as an option in 2001 but mine didn't get it:(

So it looks like I should have a FS19738 (according to my Monaco Manual) on the primary (which I believe is the roadside...all my hoses are in a bundle and hard to see which goes where yet),

and a FS1022 secondary (with the electric water sensor) on the curbside (according to my Cummins manual).

So what does your 350 ISC Dynasty have on it?
Roadside?
Curbside?

Originally Posted by Jeff753

So I have two filters. One has a plastic bowl on the bottom to drain. The other has a drain port and electrical connection (see in prior post).
Which one should be the primary?
My manual only shows the one with a drain port and electrical connection and I think it list a different part number than the one that is on my ISC.
Any 2001 350 8.3 ISC owners care to list their part numbers.

[JacobC]

Did you figure out what filter you should be using? I am about to change my primary (roadside) filter on the same coach (2001 Monaco Dynasty w/ a Cummins 350 ISC) and it appears I'm in the exact same situation you were.

The manual calls for a Raycore S3201T filter, but has a Napa 3783 filter installed (which crosses to the FS1242B filter you had installed).

[AFChap]

My 2002 ISC came with only an FS-1022 with water bowl & drain installed after the lift pump. That of course has the water in fuel wiring connected. When crud in the fuel this past summer took out the lift pump (at apx 106k mi), I told them to add a 2nd filter. Cummins SW in Albuquerque added an FS-1000 before the lift pump.

[ziaptrn]

Our 2004 350 ISC has only the one FS1022, and no other. Previous coach with a mechanical 330 Cummins 8.3L had two, and I searched and searched and searched on this one for the second filter. Not to be found.
So I'm next in line for a pre-lift pump filter, I guess :-)
At any rate - searching for filter numbers can drive you to distraction, and there is sound reasoning not to trust 'what was on there already' and simply replace.