Nose (#8) Bearing - What's the Slot For?

[goldgunner]

I'm puzzled by the longitudinal slot on the outside of the Nose (#8) Bearing opposite the locating hole-pin.

I can't see any function for the slot...is there?

Seems like an oil leak path, albeit into the O-Ring seal...

I think some people, like Henry the engine builder, recommend a thin coating of Curil-T on the O.D. of the nose bearing: what about the slot? Fill it with Curil-T?

[Eagledriver]

That is a oil return slot. Don't fill it with anything and take care to not let any case sealant get in it. I think the bottom of the bearing may have an oil feed (not sure about that). If it does then some oil will ooze out around the bearing and be blocked by the o-ring. The oil then must have an escape path or it will leak past the o-ring.

-Andy

[ChrisBennet]

Wayne's book recommends Curil-T, Henry recommends Threebond 1211 for sealing the #8.

The Threebond 1211 does the work that the O-ring and the return channel didn't do very well (sometimes). Personally, I would trust the sealing to the 1211 and fill the groove.

That said, except when I put too much 574 on the case halves once (classic newbie mistake), I've never had one leak at the #8 with or without sealant.
-Chris

[cgarr]

Looking at the slot, since its midway up in the case and not at the bottom, I would guess it is there to equalize pressure and allow the o-ring to work as it should, I would not block the passage

[lindemans]

NO GUYS !!!!

Make sure you have the right manuals at hand when putting an 911 engine back together (such as Wayne's Bible.....):

This slot MUST fit a dowel pin in one of the case-halves.
Therefore the #8 bearing must be properly aligned when mating the halves.

Not having the dowel pin in place may lead to this bearing spinning in the case instead of the crank in the bearing.....

[goldgunner]

uh, no...
opposite the slot is the mating hole to the alignment dowel.