DDK - Die Deutschen Klassiker

I have recently purchased my first classic Porsche 68 912. aftre driving about 600 miles with great performance and a big smile, I desided to have it serviced and the rear main oil seal changed as it had a small leak.

Took it to a classic porsche mechanic recommended by a DDKer and had the work done. the mechanic commented on how nice the car is 'no hidden suprises with this one'.

after driving it home looked under the engine lid to find oil all over the right hand side of the engine. Back to the garage.

Mechanic couldn't find any obvious leaks but commented that the leak only seemed to occur above 3000 revs. thinks that the increased oil pressure from the oil change may be reason for the problem only being aparent after it was in his garage.

Compression test shows that cylinder 4 is at only 64%. He thinks it may be a piston ring and that a top end rebuild may be required.

Cylinder four is on the left of the engine oil leak seams to be the right?
what other sympoms would be expected with this kind of failure?
are top end rebuilds succesful or do they cause problems later with the bottem end?

Your thoughts and advise would be helpful

Many thanks

before you decide to do anything drastic, check that the oil level hasn't been overfilled. Did they check the rocker clearances? if so did they refit the valve cover properly, this could be the source of oil everywhere.

no.4 at 64%, 64% of what? Isn't compression usually measured in PSI.

Sorry I can't be much more help

Also worth checking that the clearances are still correct: if they've been mis-adjusted and one's tight, or one was already tight of course, that could cause your compression problem.

As Nige says, '64%' is an odd way of expressing it: perhaps he meant 64 PSI which is not good. Don't panic too much yet though: lets face it, if it was fine, and nothing much has happened to it, it's much more likely to be one or two simple, coincidental things that have combined to give you an easily-sorted fright .

Be interested to hear the outcome ...

HI have a look at the tinwork screws near the carbs , as some have holes through into the rocker box, and if the screw comes out!!, oil leak, then again it is prob' the rocker cover gasket slipped in side if the clearances have been checked.

regards mike

All god advise from the guys before me.

Let us know how you get on.

Sorry I did mean to say "GOOD advise" but God works as well !!!!