Pelican Parts Forums - 3.0L Rebuild at 250k miles

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Quote:

Originally Posted by '76 911S 3.0 (Post 8477809)

The Drei Bond 1209 (3Bond) is the case sealant the Porsche dealership sells and is what is used on the 996 and 997 GT3 cases. As far as the Loctite on the o-rings, that is what was recommended to my by the engine builder I consult...

So Drei Bond is in the arena with other modern day case sealants? Great. I have not seen it discussed by any of the builders until now.

Loctite 574 is an anaerobic sealant used to seal flat surfaces. It was the standard used by Porsche on all air cooled motors; though it appears that on the water cooled motors, Porsche now uses Drei Bond. That is progress.

I've never seen nor heard discussed using Loctite 574 in conjunction with O-rings. Specifically, on the 911 case through bolts, builders usually install the O-rings dry or use only a little bit of engine oil, teflon paste, or Curall T in conjunction with O-rings to seal that area from external leaks. Since 574 is an anaerobic sealant, it sets up in the absence of air and does not form a "flexible" seal; whereas, O-rings are designed to accommodate the thermal movement of the case bolts relative to the case while still holding a seal. So, unless you can site where Porsche stipulates its use in this area, I would suggest that you consider what the prominent builders use. And, as I've stated, I've never seen Loctite 574 touted for sealing through case bolts. Perhaps someone can point out where that has been done before.

IIRC Nick Fulljames uses 574 on all the o-rings as well as on everything else in his videos. He obviously knows his way around a 911 engine, but I don't plan on mimicking that part of his engine builds.

what did you do with your cylinders? Are they the originals bored and recoated or something else?

I am thinking of doing the same with my 3.2 in terms of JE pistons and rebored and coated cylinders.

Did anything else need to be done to the pistons or used straight out of the box? Also, did you use the original 127mm rods?

An update...dyno'd the engine today, made decent numbers on a Mustang Dyno

Still on stock CIS with WUR recurved. 12.7:1 AFR at WOT. I will be modifying the stock CIS intake for an AEM Infinity 506 install in the near future.

204 wtq from ~3500-5000rpm
193 whp at 6000rpm

Dyno Graph:

http://forums.pelicanparts.com/uploa...1449694646.jpg