sealant for cyl. gaskets

[Tori]

Hate starting new threads all the time, but i need to get going on this motor,.... what sealant should i use for the copper cyl. to case gasket. Waynes book says to use the case sealer, but since i didn't split the case, i don't have any and wonder what else i can use.

Would Yamabond work ?

[Henry Schmidt]

Curil T

[Tori]

Thanks Henry, suppose i'll have to mail order that. Was hoping to find something local and keep trucking with this....

[trond]

I used nothing at all on the copper cyl base gaskets, out of ignorance. Has not leaked a drop since 4 years or so. Maybe not so critical, copper will seal pretty well by itself. Next time I will be using the thinnest layer of curitT

[Eagledriver]

Curil T is great. I use non hardening permatex because it's available everywhere. I disagree with Wayne's advice on using case sealant. You should use a non hardening sealant because you need the cylinders to seat fully into the case when you torque the headstuds. If you use a hard sealant then it might dry before you finish putting the cylinders and heads on. This would result in variations of cylinder height.

-Andy

[Henry Schmidt]

The reasoning behind using Curil T is that it is non-hardening. This allows the cylinder to move without disturbing the seal. With heat expansion, the cylinder to case to head joints are constantly moving.
The copper gasket (in a perfect world) should work without additional sealant but with these old engines "perfect" is illusive.
We generally put a thin bead of Curil T in the corner of the cylinder where the spigot meets the base. This seals the cylinder to the case rather than coating the gasket.
A fine distinction but it seems to work well. It also seems to make more sense when dealing with the 3.6 base o-ring.