Need help with diagnostics please . . .

Discussion in 'Diesel Engines' started by L'eau.Life, Feb 14, 2014.

  1. french44
    Joined: Mar 2006
    Posts: 37
    Likes: 2, Points: 8, Legacy Rep: 63
    Location: kinshasa mwanza brazza

    french44 Junior Member

    so : no over tem, no over oil pressure, no black smoke with dust. it could be an advance problem check the sensor it was a problem on QD32 on 4*4 also the injection solenoid Nissan knows this trouble on 4*4 it's same engine. try to run the engine without load to see if you get more rpm than 3000 may be the cutting injection point is not well adjusted. What is version of engine Mechanical injection ? or other ?
     
  2. L'eau.Life
    Joined: Jan 2008
    Posts: 71
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Bay of Islands, New Zealand

    L'eau.Life Junior Member

    Basic QD32 mechanical injection from 2WD Navara. Engine free revs off the gauge (4000+RPM)
    Thanks, Alan
     
  3. powerabout
    Joined: Nov 2007
    Posts: 2,903
    Likes: 61, Points: 48, Legacy Rep: 719
    Location: Melbourne/Singapore/Italy

    powerabout Senior Member

    Have you askedgarret if those pumps are capable of pumping twice the fuel at wot than the built spec.
    They can only pump max fuel as per their settings
    All that fuel is going somewhere?
     
  4. L'eau.Life
    Joined: Jan 2008
    Posts: 71
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Bay of Islands, New Zealand

    L'eau.Life Junior Member

    The pump delivers way more than the engine needs and recirculates the excess. Hoping to get the guy from Garrett to visit the boat - just trying to find a time that works for everyone :)
     
  5. Baltic Bandit

    Baltic Bandit Previous Member

    any chance that you have something binding or off center from the tranny aft?
     
  6. powerabout
    Joined: Nov 2007
    Posts: 2,903
    Likes: 61, Points: 48, Legacy Rep: 719
    Location: Melbourne/Singapore/Italy

    powerabout Senior Member

    If its easy job I would swap the injection pumps over
    That will solve that question
     
  7. L'eau.Life
    Joined: Jan 2008
    Posts: 71
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Bay of Islands, New Zealand

    L'eau.Life Junior Member

    @Baltic Bandit
    Well, we looked at that and I spun the prop by hand when I dived and it turns very freely in neutral. When I select drive both motors drop about the same (100-ish RPM) and there is no evidence of any binding. I've run about 50hrs while this deterioration has been occurring and if it was a significant dragging I would have expected some sort of failure or other indication.
    Many thanks.
     
  8. powerabout
    Joined: Nov 2007
    Posts: 2,903
    Likes: 61, Points: 48, Legacy Rep: 719
    Location: Melbourne/Singapore/Italy

    powerabout Senior Member

    Yes but it can only inject to the max fuel setting
    Hard to believe that that setting allows twice the fuel of what the good engine uses at full load.
    Thats like a pump for a turbo engine delivery full fuel when there is no boost
    Volume wise the pump shop should be able to tell you how much fuel that can pump at its correct setting
     
  9. L'eau.Life
    Joined: Jan 2008
    Posts: 71
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Bay of Islands, New Zealand

    L'eau.Life Junior Member

    @powerabout
    In terms of access the other engine was definitely "born out wedlock"! It is a major to get to the pump involving removal of the full galley. If it comes to it I'll have to follow that path but in that case will probably wait until winter. At least for the moment the boat is usable and our weather has been stunning recently.
    I'll ask the question re pump capacity/flow.
    Thanks again!
     
  10. Baltic Bandit

    Baltic Bandit Previous Member

    So I assume from the access issues that my next idea is not viable - namely to pull the trannies. you could have something on the output bearing side that only starts to show up at higher revs, some sort of binding that is increasing friction and hence transferring more heat back into the engine. though from the amount of heat you describe, it probably would have failed catastrophically before this.

    Enjoy your weather. its dreary in Paris and everyone is coughing fighting a nasty grippe that has been going around.... :-(
     
  11. quequen
    Joined: Jul 2009
    Posts: 369
    Likes: 15, Points: 28, Legacy Rep: 199
    Location: argentina

    quequen Senior Member

    White smoke and overconsumption in a diesel engine is often caused by a damaged fuel pump.
    Pump damage often comes from internal oxidation caused by water into the fuel's filters.
    Hope it helps, that's what my mechanic says...

    -
     
  12. L'eau.Life
    Joined: Jan 2008
    Posts: 71
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Bay of Islands, New Zealand

    L'eau.Life Junior Member

    Thanks quequen - we have had the pump checked and overhauled and changed the filters. No evidence of water. :-(
     
  13. Westfield 11
    Joined: Apr 2008
    Posts: 215
    Likes: 8, Points: 0, Legacy Rep: 95
    Location: Los Angeles

    Westfield 11 Senior Member

    How long ago was the manifold repaired and what was done to it? Is it possible that this could be your problem?
     
  14. L'eau.Life
    Joined: Jan 2008
    Posts: 71
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Bay of Islands, New Zealand

    L'eau.Life Junior Member

    @Westfield 11
    Manifold repair was after the problem started. I've had the manifold off and inspected two weeks ago and no issues there.
    Thanks, AB
     

  15. L'eau.Life
    Joined: Jan 2008
    Posts: 71
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Bay of Islands, New Zealand

    L'eau.Life Junior Member

    Manifold repair . . .

    This is why - the original welds had no penetration whatsoever and with [probably] 30-odd kilos of steel and water hanging on them, this was the result!
    Fortunately when it let go I was tied up alongside investigating the engine problem . . .
     

    Attached Files:

Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.