64 Impala Engine Rebuild
About 2 months ago (June 2003) I was on my way to play paintball with some friends in Leesburg, VA on a Saturday morning when I blew a fan belt and overheated. I stopped, and refilled the radiator after the engine cooled, drove the car to a friends house and left from there to go play paintball. Over the course of the next few weeks the car started running rough and I knew the head gasket was on it's way south.
I did it Myself!
With Tools and Instruction
I decided on August 22, 2003 to change the head gaskets. I backed the car into the driveway, put it on the ramps and started taking it apart. As I removed the front of the motor I was anticipating putting it back together that Sunday afternoon. It looked like it was going to be a simple job, just yank the distributor out and pop off the intake manifold. I ran into a challenge with the head bolts when I realized my toy of a 3/8 ratchet wasn't up to the job so I walked to Standard Auto Parts about 3 blocks away to pick up a 1/2 inch drive torque wrench. Alas the heads came off. My close friend Murphy, of Murphy's law, decided I should find the unexpected and I discovered a collapsed ring in cylinder number 8. The gasket job just turned into an engine rebuild. Notice the clean crescent shaped area on the lower side of piston number 8 where the oil was washing past the piston. This is where the piston rings had collapsed.
I wasn't too reluctant to do it since I used to do this for a living when I was just out of high school. I grew up in a mechanical family, my father was in the transmission business when I was a teenager. I was a willing recruit then because I liked playing with cars. This evolved from helping yank trannies out after school and on weekends to tearing them down, tearing down engines, differentials etc. When my father struck a deal with a guy that owned a few speed shops with their own machine shop I couldn't pull myself away from the place. Needless to say I was eventually working for him too building street rods and doing a lot of generally hard core automotive work.
The cleanup job
I stripped the engine down in my "spare" time over the course of the next few days. I felt ambitious about it and thought it would be a good idea to refinish a lot of extra parts like the air cleaner, converter cover, all the brackets etc. After starting to sand the air cleaner one afternoon and spending way too much time on it I realized the smart thing to do would be to take the parts to Charlie's Machine Shop in Glen Burnie, Md and get them to hot tank these parts, at least that would save me from blistered finger tips from sanding the nooks and crannies in the parts. This decision saved about 2 days worth of work. I already had a sanding episode a couple of weeks earlier when I sanded down all the wheels by hand and primed and painted them.
Of course I still cleaned the heads and block myself, after all I still had to hone the cylinders, clean the pistons and do a general health check on the parts before deciding how much work was in store for me or the machine shop. As it turned out the pistons were in excellent condition for 120,000 miles, I have seen far worse than this and now these pistons were going back in the motor. It really was a good thing that I parked the car while it was still running rather than wait for it to implode and die. The overall damage to internal parts was limited to normal wear and tear.
The cam was in really bad shape though, I knew that going into it when it was only a head gasket job since I had adjusted the valves several times before and found a couple of cylinders had really worn cam lobes with very little lift. Luckily there was no mushrooming on the lifter bottoms and they came out with minimal persuasion. Take note of the picture where I highlight the offending lobe in green, this is supposed to be the high spot on the cam lobe and is supposed to look like the one immediately behind it. There were a few others that were worn as well but this was the worst of them. The cam bearings were near perfect after cleaning as is usually found in these old chevys