This past Friday night, I pulled the Cavalier into the shop and began disassembling it. I was anticipating finding a failed head gasket. Much to my surprise the gasket had no failed.
After verifying no cracks and no warpage, Saturday morning I began disassembling the head to inspect the valves. I knew the issue was limited to cylinder #2 and after removing the #2 exhaust valve, it became clear what the issue was. The valve guide was worn to the point that there was over 1/8″ of play! It was worn to the point the valve stem had nearly worn all the way through the side of the guide. I have no idea how it didn’t drop a valve. Two of the exhaust valves were pitted, two looked as if they were relatively new and almost all the valve seals were broke.
Instead of having a week of downtime while I had new guides installed and a valve job performed, I pulled the head off of a 95′ parts Cavalier we have here at the shop. It was pretty carboned up and the valves were heavily carboned. However, the guides looked pretty good, and the seats were in good shape.
After three hours soaking in the parts washer, and another hour spent with wire brushes and bottle brushes, it was free of any carbon deposits and ready for assembly. The intake valves from the original head, as well as two of the exhaust valves were cleaned up and inspected. All the valves were installed and lapped as well as new seals installed. The valve springs and locks from the original head were also cleaned and switched over.
After a thrash session Sunday morning, it fired up and runs like a top. Compression is now even among all cylinders, the miss is gone, and mileage has doubles with an average of 29.5mpg. Not bad for a three speed auto car!