Well, I cleaned the mating surfaces as best I could. I scraped carefully with a razor blade, then finished with a little nylon brush on a dremel. Installed the new head gasket, torqued to 30 ft-lbs in the proper pattern going 10 ft-lbs at a time. I oiled the head bolt threads with 30 weight oil. The bolts seemed in good shape (fresh water boat). A few little external leaks that had developed over the years now disappeared, but the plugs still came out grey/ milky. Cylinder bores looked good (to me). My compression actually got a but worse, it was about 135 psi before the job, about 120 to 125 after. The other bank (starboard side) is also showing milky plugs, but I have not touched this side. It's compression is about 140 to 130.
I noticed in the photos that the grey stuff was on the exhaust port side on the cylinder head. I read somewhere that water can come in from a blown exhaust cover gasket? Could this be the problem, or are my heads possibly warped? I did have the high temperature alarm go off briefly last summer, so I installed a new impeller this spring.The old one was stiff, but not broken.
I've also noticed water occasionally squirting out the poppet valve hole on the starboard side of the motor. I opened it up, cleaned the spring and diaphragm. No holes, it looked in good shape.
Any suggestions welcome.
Thanks,
-Chris