Thanks folks. I'm still collecting information and trying to decide what to do. I inspected the old valves fairly carefully. All of them are covered with black carbon soot, and one of them appears to be slightly out-of-round. Maybe this one came from the cylinder that was giving me low compression (see my first post). Would a burned valve appear slightly out-of-round?? Sorry for the newbie question.
The timing gears have a lot of dried, caked oil inside the cover. This got me to wondering how the gears are oiled. Is oil sprayed between the gears and then drained back into the block by gravity?
I have not removed the caps from the rod and main bearings yet, but I'm thinking that will be next. Can I use plastigauge to check the clearance on the existing bearings? If existing bearings are not way out of spec, there should be no need to remove the crank and replace the bearings.
I'm also planning to borrow a better micrometer to check the cylinders. If the cylinders are not out of round by more than a few thousands (diameter and taper), I would think there would be no need to replace the pistons. Do rings wear out even if the cylinders meet spec (another newbie question)??
Finally, when I removed the engine, I noticed a lot of oil caked on the transmission. I'm assuming this means a leaking main seal should be replaced. If the bearing journals and cylinders meet spec, I'm thinking I'll just replace the seals and gaskets, button the thing up, and drive. If bearings and cylinders out out of whack, more work will need to be done.
