Leakless XS Assembly

[ahrma814]

For a competition engine I have copper base and head gaskets. I install the head gasket dry and put Gaskacinch on the base gasket. With a constant dose of RPM and vibration, both still weep slightly, but the base is much better since installing a Hayden Krankcase vent which apparently does it job and lowers internal engine pressure to some extent.
Craig

[waynescyclegarage]

I don't want to muddy the water here and everyone has their own secrets for sealing these engines, Heres what I do. I put the engine back as the factory did it in the first place. I use 4 bond on the metal to metal surfaces as did the factory engineers, very thin after cleaning the surfaces with brake/contact cleaner. Where there is a gasket, like base and head I use no sealer, like a new engine. If you have any leaks around cam or covers it's because it was not properly prepared or somthing else is wrong. Retorquing the head is certainly important but is not that hard, just tighten the bolts. Once a bolt is tight you should not turn it any more regardless of what your torque wrench says. If a bolt is tight and you force it further you cause damage. This is from experience and formal training and works for me. My XS is high and dry. good luck and keep it simple IMHO. wayne

[targis34]

Just 2 cents about the Cam cover seals leaking. I had the same problem and it was because the bearings hadn't been pushed in far enough. They can be installed too far out on the cam shaft and then the seals won't work right. I push the bearings in as far as they will go. It solved my problem. Pushing those bearings back can be accomplished by loosening the outer head nuts and using a brass drift. I didn't get any leakage from either the seals or head gasket when I was done.
Mike

[targis34]

I'm rebuilding another from the bottom up. I always had problems with leaks that appeared to me as coming from the side cover gaskets. After the teardown I noticed that some of the nuts on the bottom side of the engine didn't have copper washers as needed. There are 6 of them in various locations. They only had spring type washers on them and If they are leakable then those washers wouldn't stop anything. I just replaced mine to make sure there is no excuses for leaks as I move on. They were hard to get. Only at MikesXS for me.
I must say the rebuild is going much better than just doing the topend. There is NO oil to get in the way, all parts are clean. If I'm only doing the top keeping oil of all those surfaces can be a real pain.

Mike

[yamasarus]

Wayne,
I agree 100%. Been doing this for years and don't have issues. By the way, the 70 XS1 had copper washers on the outer head studs from the factory. The rubber seals came about to stop the copper from leaking and they did.