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Nose bearing and O ring were installed dry. No residue in the relief channel. Just a bit in the o ring channel.
Jason, please tell me 1209 is only for later models. I can't deal with any more options
Use Loctite 574, its the industry standard for aircooled.
Look again carefully at the nose bearing photo.
What I see is the seal incorrectly fitted, sitting proud of the top of the bearing, damage to the outside of the bearing in critical areas, a mark along the o-ring where circled AND sealant in the groove. Do I need I say more?
My advise from looking at that photo would be to buy a new bearing and seal, grease and fit the seal correctly, grease and fit a new o-ring correctly, then fit into the engine with correctly applied 574 and the front of the case will be leak free.
Wow, there is a lot going on there and not too much of it good If ever need a second opinion on an X-ray, I'm telling them to send a copy to Colin as a second opinion... We can give thanks to hi-def cameras too that o-ring does look to have a pinch?
Use Loctite 574, its the industry standard for aircooled.
Look again carefully at the nose bearing photo.
What I see is the seal incorrectly fitted, sitting proud of the top of the bearing, damage to the outside of the bearing in critical areas, a mark along the o-ring where circled AND sealant in the groove. Do I need I say more?
My advise from looking at that photo would be to buy a new bearing and seal, grease and fit the seal correctly, grease and fit a new o-ring correctly, then fit into the engine with correctly applied 574 and the front of the case will be leak free.
Bearing ordered and on its way. Thanks for the reply. I had already ordered the front seal but hadn't picked up that it wasn't properly installed in the first place!
im in the process of rebuilding my engine and have already closed the case.
but I can tell you that from the factory build when I took the motor apart, you could see the marks as posted in your pictures from the case halve seam on the oring. mine did not leak.
the Porsche factory oring is quite hard, or should I say the hardness of the Porsche oring is on the firm side.
I got my oring kit from Steve Weiner and his supplied oring for the nose bearing is more softer .
I think that because the Porsche oring is so firm, that this happens when you put the case together. its just my observation. take it for what its worth.
it not an ideal way to install an oring for a circular seal, most time you are place and oring in a bore and not pinching a bore around an oring if that makes sense.
you do need to coat the oring very lightly and make sure its not roll out of its natural orientation when you install it. and you need to lube the case halves where the oring ride in very lighty too so as the case goes together its not gripping the oring and trying to bunch it up as the case halve meet.
I think this is the problem with the factory oring. its too firm. you would have to compare the two to see what I mean.
just curious, what would be nice is if you machined off that small land, threaded a portion on the end of the bearing so you could assemble the case, slide on the oring in the bore and screw on a a machined retainer. that way no pinch oring, it replaceable in the future . I don't think that land provide much bearing support but more of a wall for the oring .
Thanks Colin..for the great info and insights..my 1990 964 engine rebuild started in June 2016 and only completed in March this year..now I wish i had found out about you then..but no knowledge is ever wasted...please keep posting!!!
Loctite 574 all the way. A little bit of red grease on the O-ring and bingo, nice dry engine. I get my gaskets and #8 nose bearing from Wrightwood Racing.
Last edited by triplezero; 05-06-2017 at 10:40 PM.
Reason: My Text never went through.
Just found these photos of Ninemeister engine builder Mark using the foam-dab technique to apply Loctite 574 to the camshaft carriers prior to assembling the heads.
Sorry for coming in ..... Is this amount of locktite 574 is enough as applied in above pic
05-03-2017, 05:36 PM
If ever need a second opinion on an X-ray, I'm telling them to send a copy to Colin as a second opinion... We can give thanks to hi-def cameras too 
that o-ring does look to have a pinch?
