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Axledragger's avatar
Axledragger
Explorer
Jan 04, 2017

Diesel engine hard to start. But runs great.HELP

I have an airstream motorhome with a Cummins diesel type C engine with only 45000 miles. I have never had a starting issue. Now It only has a problem at cold start (67 degrees) after that it starts right up and acts like it is getting plenty of fuel. I checked for fuel leaks at the injectors which looked dry, change fuel filter and fuel/water filter. I have a good charge on the battery’s which turn over very fast. Every time I try to leave campground, I run the starter for 3 times for 1 minute, then it starts. Anyone have had this problem please tell me what it needed to fix it.

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  • wolfe10's avatar
    wolfe10
    Explorer
    Jan 05, 2017
    Freightliner shows that they provided Airstream with chassis through 2006-- some with Caterpillar, some with Cummins. That is why I asked.

    You are correct, this may be an old "bullet nose" Airstream with Cummins B engine, but we really don't know.

    https://www.fcccrv.com/coaches/
  • MrWizard's avatar
    MrWizard
    Moderator
    Jan 05, 2017
    He did say air stream
    Air stream diesels were only produced for a few years in the early 90's
    Would probably be 95 or before
    This would be mechanical injection 'i think'
    Like my 95 Safari with Cummins 5.9
  • wolfe10's avatar
    wolfe10
    Explorer
    Jan 05, 2017
    Axledragger,

    Please help us to help you. We don't know if this is an older mechanical injection Cummins C or newer one. Makes it kind of hard for us to know how to answer.

    What year is your coach???
  • The_real_wild1's avatar
    The_real_wild1
    Explorer
    Jan 04, 2017
    What year is it? Lots of changes throughout the years. At that temps a grid heater won't matter so it shouldn't matter if you have one it not. It is on the intake BTW if you have one. I am thinking as other mentioned you are losing prime. Not sure if you have a hand pump or an electrical pump for prime. There should be a fuel regulator/ check valve that keeps the fuel from draining back. This may have failed as well.
  • lanerd's avatar
    lanerd
    Explorer II
    Jan 04, 2017
    I had a C7 ACERT CAT that acted the same. Always had to turn on the engine heat for abut 10 minutes or so prior to trying to start. Even then it would crank for 15 seconds or so before it would catch and I'd have to keep the starter motor running for another 5 seconds or so.

    Traded it in on our Phaeton and the 2nd owner of it said he had to replace the lift pump and then it would start like it should.

    Have no idea if that may be your problem...different engine altogether.

    Ron
  • dons2346's avatar
    dons2346
    Explorer
    Jan 04, 2017
    Just for grins and giggles, have you tried plugging in the block heater for a couple of hours before trying to start?

    I watch my volt gauge and it appears that my grid heater comes on all the time on a cold start. Watch your volatge and ee if it dips down below 12 volts. That should be a good indication that the grid heater is working.
  • Sam_Spade's avatar
    Sam_Spade
    Explorer
    Jan 04, 2017
    Bob Sue wrote:
    I'm sorry if this sounds stupid,


    Not stupid at all.

    The fuel pressure needs to be checked before starting to see if it has leaked down. If an injector is leaking, there might be a couple of puffs of REALLY black smoke just before it fires up.

    Running the starter continuously for 60 seconds, however, probably is NOT a good idea.
  • Bob_Sue's avatar
    Bob_Sue
    Explorer II
    Jan 04, 2017
    I'm sorry if this sounds stupid, but to me it sounds as if you are losing the fuel prime. Try turning the key on for a second at a time for 3 or 4 times, then crank it up. If it starts, check your fuel line and filters for leaks.

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