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oil on one cylinder

Can evidence of oil escaping between a (one) cylinder and case or cylinder and head be considered "normal" in a 48K miles 930? If this was picked up in a PPI that did not include leakdown and compression numbers, would that be the logical next step?

I have one quite knowlegable fellow (who did the PPI) telling me to be worried (like, case studs worried) and the owner's mechanic stating it to be normal. I believe it warrants compression/leakdown investigation but am open to other opinions.
Old 06-19-2010, 07:44 PM
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It's not normal. Get the comp/leak numbers but don't let his mech do it, unless you can watch.

I had oil on the top of #5 cyl/head and the leakdown was bad - broken stud on the intake side at the back. Runs like a champ though - I hope to rebuild it this winter.
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Last edited by turbocarrera; 06-19-2010 at 08:20 PM..
Old 06-19-2010, 08:14 PM
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Well, was provided leakdown numbers from the owner's mechanic today (I'd asked they be obtained by the fellow that did the PPI and that compression numbers also be reported...but that didn't happen...but it wasn't my money for this either). The numbers are reported as follows:
Cylinders 1 though 6 sequentially(%): 17,17,15,17,15,17.

This is about as far as the owner is willing to go and I can't say he hasn't done his part. The car is a mostly original (MSD box and coil installed and BBS wheels from the late 80s) '89 930...original guards red paint in really good (not perfect but as good as ~50K miles could be), camel interior, not hit, clean...8 out of 10 condition...nice for nearly 50k miles. Pretty good documentation of good maint history. 2 owners. The same owner since ~12,000 miles. I've seen and driven the car and stood under it during a PPI. The owner is asking for a reasonable offer less than $45K

thoughts?

Last edited by pavulon; 07-10-2010 at 08:14 PM..
Old 07-10-2010, 07:50 PM
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Those leakdown numbers appear high, like possibly the test was done with the engine cold rather that hot. While the absolute figures may be high, the consistency across the cylinders is perhaps a more important telltale (and in this case a good sign) as different gauges and testing methods (hot or cold engine, and amount of air pressure used) can perhaps yield varied results even for the same engine.

My thoughts? You should never have oil leaking from between the top of the cylinder and the head, that would mean oil in the combustion chamber which is a very bad sign. Oil leaking at the cylinder base or at the head/cam housing interface is not normal. Fixing it properly requires a teardown of the top-end at minimum. However, a small oil leak is not really a big deal and you can drive a car like that forever really, so long as the drips don't bother you.

More thoughts. The headstuds may be fine, and a broken one might not even show up on compression or leakdown. Best way to check those is to pull the valve covers and look for the head nuts. This is a 20+ year 930 with 50k miles. Many of these cars have at least had a top-end rebuild by that mileage. I would add at least 10k to the purchase price in my head and see if I was comfortable with that thought before pulling the trigger.
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Old 07-11-2010, 05:38 AM
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What's a reasonable offer under 45k? Is he talking about 40k, 42k, etc? Still to much money IMHO. Care can be had in great shape with less questions for less.
Old 07-11-2010, 01:52 PM
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