RV Diesel problem. 1989 6.2 Chevy V8

Discussion in 'Tech/Mech General' started by paulkearnusic, Sep 6, 2014.

  1. paulkearnusic

    paulkearnusic Read Only Funster

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    Anyone have any ideas or experience of the normally aspirated Chevy 6.2 litre diesel engine fitted to my American Tiffin motorhome?
    It was working 'spot on' on the last trip towing our Fiat tow car (I'm in a wheelchair - so I'm allowed a tow car :) ).
    The last thing it did was climb the 1 in 4 hill (1 in 3 at the bottom) hill to get back to our house.
    All seemed fine - although it took all it had to get up the hill until we loaded up last week to go off and enjoy the nice weather. I started the engine to warm up and for a couple of minutes it was fine (started first click as usual). Then, for no reason I could see, it just died and wouldn't start again.
    Wind forward and I thought that although we had indicated 1/2 tank perhaps the gauge was faulty - so we added 5 gallons from the spare cans we carry. I went online and found out how to bleed the air out, did all of that (and changed the fuel filter for good measure).
    When I tried to start up, it coughed and sputtered into life then smoothed out into the lovely V8 purr - ran for 10 minutes and died again. I re-bled the system and, again, it started ran and died.
    I can do the above as many times as I like but it simply won't run longer than 5 mins.
    I tried opening the bleed valve and running with it open (catching the diesel in a clear container) and noticed that each time it dies the fuel goes from clear to frothy.
    Each time I bleed it the fuel flow is clear for 5 minutes - then it froths up.
    It's almost as if we have an intermittent air leak. How could that be?
    When it's running, it has full power and is smooth as silk - it's just the frothy fuel that stops it.
    Does anyone have any idea what might be going on? I'm at the end of my tether and my disability prevents me from doing anything that requires bending or standing up (broken spine) - but my wife can do those bits under my guidance.

    Any ideas or suggestions.very welcome.

    Cheers

    Paul
     
  2. Snowbird

    Snowbird Funster Life Member

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    Obviously pulling air in somewhere. Thats what the frothy diesel is. The only way is to check each joint from the tank.
     
  3. paulkearnusic

    paulkearnusic Read Only Funster

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    I was dreading that might be the case.

    Best go wake the wife up with a nice cuppa - sounds like she's spending the day under the camper.
    She will be SO pleased :) .
     
  4. Snowbird

    Snowbird Funster Life Member

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    The easiest option sometimes is to run a new fuel line in.
     
  5. John Laidler

    John Laidler Funster

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    Might also be a fuel leak from where the air is getting in so she could look for a damp patch, so to speak, either around the pipe or on the ground. If it is a damaged pipe you may have to drain all the fuel out. :(
     
  6. TheCaller

    TheCaller Funster

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    A very long shot, but you could try running with the fuel tank filler open. If the filler breather has become blocked, a vacuum will start to build up & the lift pump is probably quite low pressure, so soon stops feeding fuel through.

    I say a long shot, because if the tank is half empty, I'd expect it to run a lot longer than 1o minutes before the problem showed itself.

    When you bleed it, are you getting a strong clear flow immediately after the lift pump straight away, or does it have air in it that far back?
     
  7. Leftlegger

    Leftlegger Funster

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