wirehairs
XS400 Addict
The bike: 1982 Yamaha Maxim 400. 14K on the clock. So, I had oil leaking into cylinder 1, and fowling the plug within a few minutes to the point where it wasn't igniting the fuel/air mixture. I was surprised, just because it blew 134 & 137 psi early in the restoration, so I didn't expect engine problems. I damaged my Motion Pro leak down tester, so while it was in the mail get fixed, I decided to pull the head, figuring I'd be doing this regardless. Once the exhaust and carbs were pulled, I looked in, and couldn't see any oil on the valve stems (I've got the right part?). Once I pulled the jugs off, I could see the oil by the intake valve of cylinder 1:
Cylinder 2 is nice and dry:
Here's the whole head, with gasket still on:
The gaskets get ripped when pulling things apart, so I'm unclear how I can figure out where the oil leak was. Am I correct is saying that it's not the rings, because then I'd have more oil throughout the head, and it's not leaking valve guides/stems because I couldn't see any oil on them prior to pulling the head, so it's the head-to-cylinder gasket that was leaking?
Cylinder 2 is nice and dry:
Here's the whole head, with gasket still on:
The gaskets get ripped when pulling things apart, so I'm unclear how I can figure out where the oil leak was. Am I correct is saying that it's not the rings, because then I'd have more oil throughout the head, and it's not leaking valve guides/stems because I couldn't see any oil on them prior to pulling the head, so it's the head-to-cylinder gasket that was leaking?
