copper coat or other head gasket sealant on MLS install? case assembly?

[Chuck78]

I have a freshly resurfaced 79 850 cylinder block and 79 750 head, & am using the gs1100g MLS head gasket vs a composite or custom made cometic head gasket.

I was wondering if it was still a good idea to use any products on this install, or if I should just put it on dry? On surfaces that have had sealer on them in past rebuilds, I am always upset at the difficulty in cleaning them off, so dry would be preferred as long as I am not compromising anything.

I have 72mm (+3mm overbore for gs850 sleeves) pistons, hence the gs1100g (8valve) head gasket with a 73mm bore.


Also, any tips on reassembling my case halves, particularly getting the shift forks in right? I have the crank/kickstart/trans in the top half, shift forks and drum in bottom half, going to install with top half upside down on bench. ThreeBond 1207b probably, but I also have 1211. Should I use the 1211 on the oil gallery o-ring, as it was on the flat non-recessed surface like that when I tore it apart. Clymers says do that to the base gasketsealerhaped o rings with 1211 also.

Any benefit/extra insurance to use any sealer on the head at the oil pressure corner stud passages only?

[rapidray]

Gasgacinch! Two coats on each side of gasket, head surface & block surface. Allow to dry between coats. Make SURE you get it on the dowels correctly when you set it as it will STICK!!!
Ray.

[Nessism]

The Kawasaki KZ guys fill the square cam chain tunnel O-ring groove with RTV when they use MLS type gaskets. Let dry before assembling the engine. A lot of them also swear by Copper Coat on the gaskets. Not sure what's best, but it's interesting to see the different opinions.

[Chuck78]

Hmmm....well...

Manuals say nothing about any sealant, and I absolutely despise having to clean that stuff off of the head gasket surfaces on teardowns...BUT, if it means better sealing and no chance of a leak on a straight head, then maybe I should go for it.

Big advantage over clean&dry install, anyone care to comment on? It's a 10:1 piston'd 920cc build, .004" milled off the cylinders (ebay parts salvage seller used a D.A. sander to clean up surface, sheesh!) and .002" off the head to clean up some minor scratches around the oil passages.

Ray, if you swear by Gaskacinch, then I know it must be good for high heat high performance applications. Is coating the block and head commonplace? I just thought you did the gasket both sides 2 coats. So I guess I'll have to mask it off with masking tape or a cardboard cutout of the head gasket, plus the combustion chambers. Please excuse me, still learning the ins and outs.