The Stovebolt Site Forums The Shop Area Engine Shop 1960 235 Tear Down

After an initial assessment of the the engine in our 1960 C10, I decided to tear the engine down and have a better look. I did a compression test, cylinder #2 was only producing 60 psi, cylinder #5 was about 80 psi. I added a small amount of oil to the cylinders and there was no change. I verified the valves were fully closed. I don't have any history on the engine. Removing the valve cover showed the top end to be clean, there was no sludge build up to speak of. Pulling the head revealed the engine had been rebuilt at some point, the pistons were marked 0.060. The head gasket looked intact, the valves looked good, nothing burnt, no real carbon build up. I saw nothing that would account for the loss of compression. Having the head pressure tested will hopefully shine some light on the issue. Getting the the machine shop to rework the head is a given at this point.

I pulled the rod bearing caps, the bearings were 0.010 under. there was no evident wear, nothing that would catch your finger nail. I pulled the pistons, the skirts and rings looked good. From the lack of wear it may not have had many miles on the engine since being rebuilt. There were no honing marks on the cylinder walls however. The main bearings were also 0.010 under, the crank was stamped rods 0.010, mains 0.010. The crankshaft journals showed no signs of wear. The oil pump had a cobbled together pickup screen wired over the outside.

The cam was a different story, there was significant wear on the lobes, the lifters were cupped and worn. The cam bearings showed a lot of wear. I an thinking the engine builder used the original cam and lifters and didn't replace the bearings.

At this point I'm going to mic the crank and cylinders and make a decision. I don't believe the block will need to be bored, I would hate to go any further over sized. A fresh cam, lifters and bearings are in order. A good cleaning and have the crank polished, hone the cylinders. Fresh bearings, rings and a full gasket set and I should be ready to put it back together.