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retiredtraveler's avatar
retiredtraveler
Explorer
Mar 01, 2016

5.9 Cummins fuel problem

We have a 1998 HR Endeavor with the 5.9L Cummins. Last summer a problem developed which drove my mechanic crazy. Engine would start then die. He replaced the lift pump and everything seemed fine for a while, Then it happened again, this time in my driveway. He sent out a guy who tapped the fuel filter housing and it started. He replaced the lift pump with an OEM pump. He checked all the fuel lines and blew them out. Everything worked fine. We went to Florida with no problems. After 3 months we left the campground and went 4 miles to top off the propane. Same thing happened. I called home and spoke to the actual guy who did the tapping. He explained where he had tapped and I did it. It started. Now we are in GA and it happened again. We had a mobile truck guy here. He checked the air filter and replaced the fuel filter. No cigar It fires with a squirt of ether and keeps running. He suggested the lift pump so I ordered one. This morning I have second thoughts. What are the odds 3 pumps fail? The last one with less than 2000 miles on it. Also the old fuel filter was only 1/2 full when he took it off.
Any thoughts?
Class A
  • gbopp's avatar
    gbopp
    Explorer
    Mar 01, 2016
    I do know that just because something is new does not mean it is good.
    Maybe you got a bad one.
    Did you try calling someplace like This to get a second opinion?
    It wouldn't hurt to call and talk to them, or any other place that specializes in diesel pumps? JMO
  • 45Ricochet's avatar
    45Ricochet
    Explorer
    Mar 01, 2016
    Try to read this article

    LINK

    There are a few improvements that can be done to a stock fuel system.

    FASS

    I think they have Air Dog on that site as well.
  • path1's avatar
    path1
    Explorer
    Mar 01, 2016
    Also the old fuel filter was only 1/2 full when he took it off.


    I think 1998 is 12 valve?

    Some of this link might be helpful. If your mechanic is not a "diesel" guy, he might not beware of some of 5.9 fuel problems. There is a ton if info on "poor or lack of fuel delivery". In my 2001 (which is 24 valve) I check my fuel pressure everytime I change the oil.


    http://dodgeram.org/tech/dsl/troubleshooting/12v_trouble.htm
  • retiredtraveler's avatar
    retiredtraveler
    Explorer
    Mar 01, 2016
    Thank you for the replies.
    I agree the first pump could have been bad. But 2 in a row is unlikely. The first one was an aftermarket, the second OEM.
    The engine is the 24 valve. I will poke around the links.
  • lc0338's avatar
    lc0338
    Explorer
    Mar 01, 2016
    I ran this by my diesel mechanic and here was his reply:

    Is there a chance you have the engine serial number?

    It should be an ISB 5.9L with a VP style pump. I just don't have a way of looking up an endeavor. If you do not have the ESN then if you can describe the injection pump for me I will know for sure what series of 5.9 I'm working with. Most likely it is not the fault of the lift even though it may be bad. Cummins drives the lift pump with a power transistor in the ECM. As they get older they sometimes fail. It may be causing a low voltage problem to the lift pump that causes them to fail prematurely.
  • retiredtraveler's avatar
    retiredtraveler
    Explorer
    Mar 01, 2016
    One more piece of info I neglected to mention. One of the times I was poking around under the bed I had my wife turn the key to run. I could hear the pump running but no start.
  • lc0338's avatar
    lc0338
    Explorer
    Mar 01, 2016
    Info from my mechanic after looking at the serial number up:

    OK it is what I thought it was. I would have the voltage tested at the lift pump with the lift pump and engine running. Unfortunately if it is low the correct way to fix it would be to replace the ECM. The cheap way to fix it is supply the lift pump key switch power. That is only 12 volts in the run position. You do not want the 12 volts to stay on during the cranking position of the key cycle. It sounds funny to not want 12 volts to it but VP44 injection pumps don't like fuel pressure when they are trying to start. After the start the don't like having less then 10 psi supply pressure.
  • retiredtraveler's avatar
    retiredtraveler
    Explorer
    Mar 02, 2016
    First of all thank you to all who tried to help us out. I did call a couple of the places suggested. It seems the more I read and hear the more confused I get.
    I guess if I can get the beast started with a drink of starter fluid it is time for a visit to Freightliner in Savannah.
    Again thanks to all.

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