[Vwdiesel] Head/Engine rebuild lots of questions

[Bob O Shaughnessy]

    After watching it languish on the repair lot of the VW dealer next to my
office for over a year, I finally (after turning it down twice) bought a 82
diesel Westfalia Vanagon.  The story goes that the engine lost power in a
huge way and didn't show very well on a compression test.  The owner was in
Japan for most of the year and finally told the service manager to sell it
off.  While I was having it pulled onto a trailer one of the mechanics
confided to me that he thought that all it needed was some valve work.

    The engine was mostly assembled, with a box in the passenger compartment
holding the injectors, timing belt cover, valve cover and intake air box.
Oddly, it also held ten head bolts (the 12mm ones).  I suspect that they
removed the head, but wasn't sure, as it was full of oil and coolant, and
had a visibly worn timing belt.

    Well, since I was able to get the Westy to its temporary home behind the
in-law's pole barn a few weeks back, I decided that today was ripe for
removing the head and doing some poking around.  The head came off too
easily, as the head bolts didn't seem to have been torqued down and the
exhaust manifold wasn't bolted to the down pipe (pretty sure they removed
the head at this point).

    Here's where the questions begin:  The heads are cracked between the
valves in each combustion chamber, not huge cracks, but maybe .5mm wide from
valve seat to valve seat.  Would this alone cause compression problems and
loss of power?

The valve seats seem okay and the stems aren't too carboned up.  One intake
valve stem is a bit oily though.  Oddly, the #3 compression chamber didn't
have much carbon at all coating it.  #1 and #4 looked fine, nice coating of
carbon, #2 and #3 show a bit of aluminum corrosion.

    While I had the head off, I figured that I'd try to measure the piston
crowning for the next head gasket.  I think that the dealer put the wrong
gasket on, as theirs had holes instead of notches.  Not having the proper
dial gauge, I tried using a straight edge and feeler gauges.  I'm pretty
sure that I didn't get accurate results as I measured all four pistons as
crowning at around .030", well below the threshold for the one notch gasket.
Is this a bad assumption? I'll probably get the dial gauge to time the pump
anyway.

    I'm guessing that I'll have to start with a rebuilt head, and the
rebuilt injectors I just bought, assemble the engine and see what happens.
During one of the discussions of the condition of the engine with the
service manager at the dealership, I seem to remember being told that the
compression problem may have been a bottom-end thing.  What are the chances
of this?  The van has ~114k on the odometer.

    Thanks,

_________________________________________________________

Bob O'Shaughnessy,         Columbus, OH
vanagon at columbus.rr.com
99 A3 Jetta TDI
85GL with basic Westy interior
82 Diesel Westy (with blown engine)
74 Bus (Dad's)
72 Wife, 95 Cat, 96 Cat, 98 Kid, 00 Kid, 01 Dog
25 House