2 piece rear main seal questions

[Vintage Windmills]

It seems most people don't glue the two piece seal in place from the research I've done. If there is no adhesive, what would keep the seal from spinning? even if theres enough friction, wouldn't it be cheap insurance to put adhesive on the seal. Also, I see opinions vary on what to do where the ends of the pieces meet. My instructions don't call for anything but I've heard of people using everything from superglue to sealant here. Thoughts?

[kelsfine69]

Any rubber joint i use a good sealant, intake corners etc...

[68 TT]

Originally Posted by Vintage Windmills

It seems most people don't glue the two piece seal in place from the research I've done. If there is no adhesive, what would keep the seal from spinning? even if theres enough friction, wouldn't it be cheap insurance to put adhesive on the seal. Also, I see opinions vary on what to do where the ends of the pieces meet. My instructions don't call for anything but I've heard of people using everything from superglue to sealant here. Thoughts?

Never had one spin or seen one that moved at all in over 25 years of building Chevy engines. Most likely they are compressed in place when the main cap is tightened down so they can't spin.

I wouldn't mess with the standard procedure of putting them in dry with a dab of sealant on the staggered ends. With my luck the thickness of the adhesive under the seal would mess up the seal clearance with the crank and cause it to fail prematurely. It would suck to have to do that job again not too long from now when the new seal fails.

I say play it safe and do the install like everybody else with no adhesive.

[Meatman]

Ive always installed them dry. Main thing I make sure is that the ends of seals don't meet where main cap meets block. Spin seal so ends are staggered in relation to main cap and block joint.

[old Chevy guy]

I never saw one spin and Ive never put anything as far as sealing the joint either. I agree with 68 TT I'd be afraid to have something extra in there and mess up the clearance on the bearing cap. I wouldnt stagger the joint though,besides that the direction never included that fact ,that Ive ever seen, It seems like the compresion on the seal from tightning the bearing cap is what would keep it from leaking at the joint. That would not be the case if it was turned. I never had one leak after almost 30 years of working on old Chevys. Just my two cents.

[cdowns]

putting sealant adhesive or other goop just makes more for work in the future// gazillion bazillion came off the assembly line dry i figure that is the best way to do it

[Vintage Windmills]

Thanks guys! I put it in dry and made sure there was no trace of oil on the surface where it sits. I rotated it so the ends staggered 3/8". That was what was on the felpro instructions and what I heard most frequently.

Didn't seal the ends either.

[jocko]

Originally Posted by cdowns

putting sealant adhesive or other goop just makes more for work in the future// gazillion bazillion came off the assembly line dry i figure that is the best way to do it

But at least a half a gazillion of them leaked, or we wouldn't still be chatting about it 57 years later... I agree with "put them in dry" - i.e. no glue or sealant on the backside of the seal where it meets the block, but I do think it helps to put a small amount of silicone sealant where the (staggered) ends of the two halves meet.

Actually, I'm with ya cdowns, I normally think that if it's good enough for the factory, any "improvement" I make will probably only screw it up. But in this case, even the factory finally went to a one-piece seal in recognition of the fact that these suckers leaked often enough to be a topic of conversation.

My own pers experience - I think the important thing is to make sure the ends are not aligned with the mating surface of the cap (as meatman mentioned above) - I gooned this once and, even with the above mentioned silicone, it leaked bad enough to tick me off. I tried the sneaky pete approach at a repair and I think I only made things worse. So, stagger - yes / silicone sealant - yes, but sparingly, and only where the ends of the halves meet.

My 2 cents. Worth about 1 cent.