chris951

alright guys,

I've done the oil pan gasket twice and replaced the rear main and it's still leaking. The back plug of the lower balance shaft is loose and oil all over it, the upper balance shaft has oil pooling between the block and the top of the balance shaft case. I've searched on here and can't really find a good thread on resealing the balance shafts, including clark's garage. Do you have to pull the intake to reseal the upper shaft? I am going to put a front crank seal and cam seal while I'm in that area. What parts do I need to reseal the balance shafts?

I am concerned about crankcase pressure, but I am running a catch can. When I let off the throttle under boost, the recirculation from the diverter valve I was wondering since it is in the same area as the crankcase vent, if any recirculated air could possibly cause positive crankcase pressure? My car has 181,000 miles and no blowby freerevving without boost, which I'm sure their is under boost.
Photos are welcome, so is sound advice.

potent951turbo

I can post some photos later when I get home if you want. To do the upper balance cover your going to have to pull the intake and a lot of the upper stuff, along with the turbo. To seal it you will need the new o-ring that goes on the little round disc on the back of the cover. I got mine from 944 online. As for the rest of the housing I used the Porsche loctite, I think its 474? I could be wrong on the number. And the front of housing where the balance shaft gear is etc. there are a few seals that go in there.

RajDatta

Its locktite 574. As stated, its a big task, might as well get all the seals and gaskets for the rest and call it a day.
Raj

Claus Groth

When my upper rear seal leaked, I cleaned the whole end very well and sealed it with YahamaBond 4. It stayed tight for another 75,000 miles until I took the engine out. I had no other reason to remove the balance shaft housing so that worked for me.

User 41221

Ditto to what Claus said. I routinely do this on all 944/951's that come through my garage as preventive maintenance. The lower rear balance shaft seal in particlular likes to leak, and while it may not be the "book procedure" for taking care of the problem, it sure works well and is a heck of a lot easier to do. Just hose the area down with brake kleen and then use a good quality high temp rtv and liberally slather it on the area.

Regards,

chris951

Thanks guys, I have yamabond at the shop since my boss works on bikes on the side. Can you get the oil fill tube out without pullin the intake? I thought about replacing those O-rings too.

User 41221

Nope, on a turbo, that becomes a major PITA job ad it requires a lot of disassembly. Sorry!

Regards,