Help, oil leaks....stupid me!?

[BartdeBruijn]

Hi!

I would like some advice / experience about concequences of blocked air breather hose.
After 16 years of restoring my 1969 911 2.0T I had my first start up!
It went all reasonable wel ;-)


Engine was running strong, no smoke(only first minute burning oil from assembly), no strange noises no metal in oil nor on plug-magnets of oil tank and drain plug ;-)

'Only' drawback was that after +/- 10 minutes, engine started to leak oil from several points....

Knowing how precise I sealed the engine (used all tricks from waynes book), there must have been some general issue/problem....

After a day or so I realized, in all my effort to do things right, what the reason of these oil leaks could be.....

When removing my air cleaner at first start up, also the tube from my oil tank to the air cleaner had to be removed. I closed this opening on the oil filling tube with a sealbag and tierip to ensure nothing will fall in.......but also no (not enough) crankase pressure could go out.... yep stupid me. So looking at where the oil came from and later on investigating the engine I realized that due to blow by (new cilinders/ piston rings) the crankcase will build up pressure that has no way out to the aircleaner..... This crancase pressure build-up together with oil temperature going up and therefore viscosity going down this could caus leaks half way the 20 minutes break in period.

After investigating the engine I saw small sputters on the top side of the engine to body seal!!
Beside that the engine leaked from the crankshaft seal. there was also oil on the stud thread from the valve covers and some drips on the bottom part other covers.

Way forward is to check the crankshaft seal on the rear and check torque on some covers.
Then I will put fresh oil /oilfilter in and deplug the opening and start it up again and see what happens.......often you are to scared ;-))

Any suggestions/advice....?

cheers,
Bart