[Vwdiesel] Nicks oil pressure problem

LBaird119 at aol.com LBaird119 at aol.com
Thu Sep 23 16:22:33 EDT 2004

> My question is how can this be running and getting oil
> all over the place in the head and up around my cam with such little oil
> pressure? 

  Pressure and volume are somwhat independant creatures.  In an 
open circuit, you can have gobs of flow but no pressure.

>  I checked the breather
> and you can blow air through it from the valve cover side and back through
> the intake tube side. It doesn't work like a normal PCV valve like I thought
> it would. 

  That's because it's NOTHING like a PCV.  One is not needed on a 
diesel.  With a PCV, you use vacuum partly, to pull the blowby out 
of the engine.  Without a PCV you'd loose engine vacuum through 
the carb and suck through the engine either creating a vacuum inside 
the crankcase or pulling air in through the vent.  The diesels just have 
the blowby "dump" under its own pressure, into the intake.  No pressure 
differential to be concerned about.

   The next thing for me to check is compression. Can that really> 
> tell me anything?

  If you have a broken ring it sure can.  If they just aren't seated then 
compression will still be low.

> I can have great compression but if the oil rings are
> trashed for some reason would that show on a compression test? 

  No, wouldn't show bad or broken oil rings only compression rings, 
which also control oil.

    I also am> 
> looking at the turbo. Could bad seals in that cause low pressure if it is
> eating oil from there?

  Nope, like Gary said it'd be running out somewhere.  
  Sounds like a classic case of bad intermediate shaft bearings or a 
worn oil pump.  You DID replace the intermediate bearings on 
rebuild didn't you?  It's a must.  The oil pressure and oil consumption 
are two different issues you have going, most likely. 
  If you're unsure of the seatage of your rings, put your heaviest friends 
in each seat, load up the trunk and go driving for a couple hours.  
Hitt the throttle and when you get to speed or just above, let off to 
5 or 10 below, floor it again, let off again.  Do this to some degree 
the whole time.  When you get back, treat your friends to their 
favorite beverage as you explain your ludicris driving habbit.  ;-)
If blowby and oil consumption don't improve, you likely have a 
ring problem.  :(

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