After a nice Sunday drive and nearly home, suddenly the engine made a terrible noise. I almost seemed as if a bearing had failed or a piston had come adrift. Immediately I stopped, and it was very clear that only the two front cylinders were firing, but otherwise the engine seemed alright. No oil or water leaks at all, so I decided to slowly drive home.At home I once again determined that there really was no compression on cylinders 2 and 3. Because there was no steam coming out of the exhaust and no pressure on the crankcase, it looked like the head gasket between the two rear cylinders had burnt through.
The head came off easily. The question now was of course whether the head and block were still straight or needed to be skimmed. With my vintage steel ruler and the smallest feeler gauge I couldn't find any bumps or dents, so I decided the head and block were still level.
After some thorough cleaning, light sanding with a small block, I replaced the head with a new gasket. I tightened the head bolts in the correct sequence as discribed in manual I adjusted the valve clearance using the well-known rule of nine. When everything was in place, it was a bit of an anti-climax because the engine started without a fuss.
