Quandry

[J P Stein]

I'm settin' here looking at my 2.7L short block.

I've torn it down to that point for, at minimum, a top end job. 7 seasons of autocross floggings got it to the point of massive leakdown....and scored Nikasil cylinders. The clown that put it together (that would be me) neglected to check/set ring end gaps......too tight.

Other than that, the guts look great. Oil pressure was good, guides are tight, intake ports/valves are clean enough to eat off of, exhaust valves have little carbon buildup on their backsides. The pistons (9.7 :1 Shastas) show a little contact area on their skirts, but the pins are now tight in their bores....they used to slip in. I suspect they have ovaled a bit....there is not much meat below the pin bores.This looks like a good time for some 10.3:1 pistons & race gas.

Enuff....to the point. There has been a small pressure oil leak around the outside of the #8 bearing since day one. The O ring & silicone grease didn't do the job. I've had several trailer park engineering schemes to cure the leak without splitting the cases, but none are surefire & all are hokie. So, to cure the thing what is a good sealent for the # 8 bearing assuming I split em'.

[Henry Schmidt]

If you split the case to reseal it I recommend the following application.

Case sealing suggestions :

Outer case halves perimeter : Threebond 1104

Bearing web surfaces: Loctite 574

#8 Bearing O-Ring: Threebond 1211

Case Thru Bolts: Dow Corning 55 on Green Viton O-Rings

Flywheel Seal: dry

Front pulley Seal: dry

Intermediate Shaft Cover to Case: o-ring dry, gasket style 574

Oil Breather Cover to Case: Loctite 574

Cylinders to Case: Curil T

Cam Towers to Cylinder Heads: Threebond 1104

Cam Chain Housings to Case: gaskets Loctite 574

Cam Chain Housings to Cam Towers: gasket Loctite 574

Cam Chain Housing Cover to Cam Chain Housing: Gasket Loctite574

Gaskets: Thin coat of Loctite 574

[J P Stein]

Thank you, Henry.

[dweymer]

Has 1194 replaced 1104?

[MatthewBrum]

I think it has, I believe that 1194 works the same but contains less lead. I just purchased some 1104 and got 1194.

[J P Stein]

Split the case today. I found a few flaws on the OD of the #8 bearing....no wonder the SOB was leaking. I'll spring for a new one but will still use sealant on it. Everything else was quite nice.

[Henry Schmidt]

If you measure the #8 main bearing saddle you'll find that is not even close to being round. We have measured over .015" ovality in mag cases and in one case .014" in an aluminum case.

Gluing this bearing feels wrong to anyone with mechanical expertise but glue it you must.

Could you avoid glue because you feel lucking? of course by why waist your luck on something like this, buy a lottery ticket if you feel that lucky.