GRUWEZ

Hi guys,
After having replaced all seals on the oil pump, the cam towers and having replaced the crankshaft front oil seal, I am still faced with a major leak at the front of the engine.
Have a look at this video:


You can see the oil leak onto the floor at the 5 o'clock position, bottom right of the harmonic balancer. This is on a cold engine, so you can only imagine what the situation is like when the oil becomes hotter and thinner.
Basically I will have to take everything apart again and check what went wrong. Crankshaft front oil seal was flush upon installation.
Any tips to get it right this time?
Thanks

Mrmerlin

either the oil pump or the front main seal in that order, chances are good the radial seal was damaged while sliding in the oil pump center gear
NOTE make sure that the gears in the oil pump have the dot facing the block

GRUWEZ

Thanks for the feedback. Is the "radial seal" you are referring to, the one that sits around the oil pump centre shaft? If so, is it a better strategy to install the center gear first and then press the new seal into place?
Also thanks for the heads up on the oil pump gear dots. I am 100% sure the gears are installed correctly.
Regards

GregBBRD

The small round seal where the drive shaft of the center oil pump gear goes through.

If you aren't super careful, a lip of the seal will become inverted, when the shaft is pushed through.

Porsche made a special guide tool, for that seal, to prevent this from occurring.

GRUWEZ

Thanks. This is what I found online.
https://www.porscherepair.us/porsche...-oil-pump.html

It looks like the shaft seal can be replaced without removing the oil pump. I don't have the special tools though. Is there a trick to do it properly without the tools?

GRUWEZ

I took some photos right after I had reinstalled the oil pump. I am not sure if it is visible from these if the oil pump shaft seal was damaged.

Mrmerlin

take the front cover off then remove the T belt,
then put a gun on the oil pump and spin it you will find the leak.
NOTE you could have also pinched the O ring did you use DC111 on the O ring?

GRUWEZ

Excellent tip, Stan. Thanks. So just apply shop pressure on the oil pump gear and let it spin to create oil pressure in the lubrication circuit...?
And yes, I applied DC111 on the oil pump O ring.

belgiumbarry

shop pressure ?
spin it with a drill ... so yes, creating oil pressure on the hole circuit. You will even feel "torque" when pressure comes in.

GRUWEZ

Yes, that's what I meant.

Mrmerlin

put a bolt into the tensioner hole so oil wont pump out.
Also remove the oil pump gear to see things easier before you use an airgun to spin the oil pump

GRUWEZ

Sounds like a plan. Thanks for the input. I know what to do.

Mrmerlin

PS it would be a good idea to spray some WD 40 into that idler bearing after you remove it and let it sit on a paper towel to drain out

edlocke

I'm very interested in this thread, mostly out of amazement. A 1980 928 that you are trying to get to not leak oil? Wow, you seek the Grail!

I just bought a drip pan - much easier.

zinn81

Did you really buy a drip pan? if so whats the part number, I might purchase one also. I think I have a valve cover gasket leak on my 81.