[Vwdiesel] Ring job

[Val Christian]

Whenever I have a cylinder head off, I evaluate whether I want to
rebuild it.  At the same time, based upon time on the engine,
any known compression data, and the bore condition, I evaluate
whether I want to do the rings.  On VW diesels that I've owned,
I've never had to rebore.  (Close, though.)

On rod and main bearings, I plastigauge them, and decide whether they
need replacement.  They're not real expensive.  I also look at the oil
pump.  My history is that I've never replaced main or rod bearings
with the exception on one rod (and bearing) after a valve collision
(the cog belt pulley on the valve train slipped on a 1.5L diesel...they
had no key).  In my experience, the oil pump needs service before the
main and rod bearings so.

I had one VW Rabbit with over 400K miles, and it had gone through
two cyl head rebuilds, and had a bunch of seals replaced, but the
rod, and mains were good when I pulled the engine from the rotting
body.

Your mileage may vary.

Val


ps: A local pilot, aerial photo outfit owner and statistician did a 25 year
analysis of time-based maintenance vs. conditional maintenance, on aircraft
and aircraft engines.  Time-based maintenance is the gold standard in
aircraft maintenance, and regulations are written around it.  His findings
were that conditional based maintenance enhanced uptime, and reduced
maintenance costs by a wide margin.  The number of in-flight system and
engine failures was also less (although with only about 125 planes in the
study, the results are not as statistically significant).  Ten years into
his study, I changed my way of thinking.  Conditional based.