ULSD 1 Cummins 0

[Jgolden]

Cummins info from 2005

As info:

No doubt this is old news to many. Just happened to read it elsewere.



Early Warning

Lift Pump Leakage Due to Ultra Low Sulfur

Diesel Fuel

Summary of the Early Warning

This Early Warning informs the field of a potential lift pump fuel leak, if a customer switches to

Ultra Low Sulfur Diesel (ULSD) fuel after using Low Sulfur Diesel (LSD) fuel.

Affected Engines

This warning affects ISB and QSB CM550, ISC, QSC, ISL, and QSL CM554 engines.

Symptoms and Observations

If a fleet changes fuel from LSD to ULSD, the lift pump can leak between the bracket and the

lift pump body or at the electrical connector.

Failure Verification

If a fuel leak appears on the lift pump, determine if the customer has begun to use ULSD fuel

recently.

Early Warning Number Revision Level Date

E05033 03-AUG-2005

Engine Family Fuel System

6B, B5. 9

6C, C8. 3

ISL, QSL9

Bosch VP44 - ISB

CAPS - ISC, QSC8. 3, ISL, QSL9

Bosch VP44 - ISB

Design Application Market Application

Automotive All

Industrial Agriculture

Industrial Construction

Marine Propulsion Marine

Suspected Cause

There is a nitrile gasket between the lift pump body and the bracket. Once the nitrile gasket

absorbs fuel, the gasket expands and seals. If the fuel type is changed from LSD to ULSD, the

nitrile gasket will shrink and no longer seal, causing a fuel leak.

Potential Component Damage Assessment

None

Repair Instructions

To avoid fuel leaks when changing to ULSD fuel, customers ought to consider replacing the lift

pump as well. The table below lists the present part numbers for 12-VDC and 24-VDC lift

pumps.

Requested Failure Information

None

Last Modified: 08-Aug-2005

Copyright© 2005

Cummins, Inc.

All rights reserved

Lift Pump Part Numbers

Engine Family VDC Part Number

ISC, ISL, QSL, QSC 12 3949085 and 3939894

ISC, ISL, QSL, QSC 24 3939898 and 3949086

ISB, QSB 12 3990105

ISB, QSB 24 3990106

 

[Nate]

My lift pump has been weeping a bit. I'm going to wait until it actually is making a small puddle to replace it though.



Orginal 1998 one with 171,000 miles :eek



We have been running ULSD at work (Air Force) for over a year now. We have several 1990 CTDs. We lost 1 injection pump and a fuel sending unit on another (not sure if that one was even because of the ULSD). Also we have one that's got something wrong in the injection pump I think. The first 1/2 of the pedal is almost nothing above idle, yet it's moving the injection pump arm. (or whatever it's called... I'm not very up to speed on the 1st gen setups).



It sucks, but I suppose it's a small sacrafic to make for less pollution in my opinion.

 

[jdross440]

In Arkansas mine inj pump starting leaking about 2 weeks after switching to ULSD. I took it off and resealed it and then about a week later the seal between the intake manifold and the fuel heater started leaking. I've noticed my lift pump is a little damp around the weep hole but will wait for a bigger leak to replace it.

 

[GIT-R-DONE]

Here is a question for you guys that have had to re-seal you pumps. Did you use factory DC or Bosch seals/gaskets for these pumps or are they special seals that you are replacing them with?



I keep hearing of people replacing the seals, but they dont say if they are NOS or something newer that has the USLD in mind.



?

 

[cerberusiam]

Here is a question for you guys that have had to re-seal you pumps. Did you use factory DC or Bosch seals/gaskets for these pumps or are they special seals that you are replacing them with?



I keep hearing of people replacing the seals, but they dont say if they are NOS or something newer that has the USLD in mind.



?

All the seal kits you get now should be Viton unless they have been collecting dust for the last 10 years. I believe about 1996 everything was switched to the new seal materials. Probably checking for viton would be a good idea.

 

[GIT-R-DONE]

How about Seal kits for the VE pumps? Do they sell just the kits or do you have to buy a whole rebuild kit? P/n's for seal kits.



I may have to do this in the near future, as mine hasnt seen the USLD yet. Getting closer to the final product... Oo.

 

[jdross440]

I bought a Bosch seal kit from a local injection rebuilder. They are the new Viton material. The kit was $21. 00. They wanted $600 to reseal it and replace any worn parts. I said no thank you, all I want are the seals.

 

[RSchwarzli]

I have not noticed any leaks, but I did notice a tone change in my motor upon using my first tank of ULSD. I thought I was loosing my hearing as the pump was not even marked ULSD in the summer around here. I only found out weeks later that around the time my motor sounded different was around the time they changed the fuel... ...



Robert

 

[JLEONARD]

First of all... knock on wood... .



I have been running ULSD since mid Oct. . at least that's when they started to purge the tanks with it. I just went outside and did a visual inspection and found no leaks around the inj or lift pump. The only spots under the truck are from the puke tube.

I use additive on every fill up... normally I use FPPF brand.



Again... . knock on wood... . salt over the shoulder..... fingers crossed..... eyes crossed... .



But what I have noticed is ever since I started using USLD my hood paint has been flaking off. . oh wait. . that's just coincidence. :-laf

Jay