Thanks for the warm welcome folks. I can see already that I'll like it here. I sense some good knowledge and experience in the forum. I find these forums extremely valuable in enabling me to service and maintain the car. Using my own to hands, my experience, along with some guidance from others. I have yet to meet another owner of the same car, so the internet with these groups, put in contact with you folks from all over the world.
As @Plymouthy Adams mentioned, #5 intake valve suffered a collision. It is bent and stuck open. The story on the valve goes like this:
Last Saturday, 1 week ago, I wanted to go to a local car show. The car has only been in my possession for 1 month so far. I have been working a little on it almost everyday. Checking things over. Fixing little things. Finding problems and improving them. The previous owner had missed some simple things that I found like, 1 missing exhaust flange nut at pipe to manifold. 2 missing manifold nuts at head. The 2 carb mounting nuts were coming loose. Little stuff, no big deal.
I have put about 400 miles on the car so far, but still had more work to do, to earn its trust. I had yet to pull and inspect the spark plugs or do a compression test.
I pulled the spark plugs one at a time. I inspected, cleaned, gapped them and re-installed them. After that the car ran like crap. I was struggling to understand what I had done. I have pulled and installed plugs many many times over my life. Such a simple task. There was nothing complicated here to cause a problem. I began thinking about what I had done, racking my brain with no solution. So I began throwing parts at it. I installed new spark plugs, new coil wires, new points, new condenser, all with no improvement. I checked TDC against the distributor. All good. The primary and secondary ignition systems all seemed to be in good shape.
I had to take a few breaks as the frustration mounted. I took my time and tried to stay calm, but still things were not adding up. Time for a compression test. I found that the spark plug holes in the head are recessed quite a bit. A bought some adaptors for my compression gage so I could safely seal up the hole and not plunge to deep into the cylinder with the adaptors. I pulled all plugs on Wed night and took a compression test. All were fairly low, with 5 and 6 holes dead, at 0 psi. I proceeded to pull the head, and what you see above is what I found. a bent valve on #5. Also #6 valves are coated pretty good with carbon and not sealing great either. In fact all the valves need dressing up. Which I believe is why I measured low compression readings. The car did not burn any oil that was visible.
I racked my brain further to figure out what caused a bent valve. After pulling the head, I removed all the built up carbon with a brass wire wheel in a drill. I found slight bruises in the combustion chamber of the head/ Something went into the cylinder and took a merry go round ride. The cylinder walls are fine. no scoring. I am lucky there. I can only assume what happened. I suspect the previous owner dropped a small nut or washer and could not find it. It landed right down in the dish beside a spark plug. It sat there for some time. Until I changed he plus. Leaning over the fenders to pull plugs, I did not see it on the back side of a plug. I proceed to pull the plug, and it drops in, unknown to me. It sits on the intake valve, which is directly under the plug hole.
As soon as I attempted to fire up the engine, contact is made as the valve rises to open. The small fastener gets bounced around a few times and the bruises the combustion chamber.
I have ordered parts to replace all valves at #5 and #6. I will pull all valves, de-carbon them, and deck area of block. I hope to lap in the new valves and re-seal all the others. The parts won't be here for about another week. Today, I will proceed to hopefully pull all valves and start cleaning. I have not found the culprit fastener yet that went through the spark plug hole. I am hoping to find it in a manifold today.
I heard someone in another form, mention that the water distribution tube may also be suspect. If you look, you'll see #5 and #6 valve are carbon'd up more than any other cylinder. If they are not getting the cooling, this may be a contributing factor. I suspect 5 and 6 were in need of service, then this valve collision happened and was the final nail in the coffin.
Here you can see the build up on 5 & 6 valves. That light scuff mark in#5 cylinder is of concern. It appears to be up into the top ridge area. I am not sure what would cause that. It does not feel excessive. The walls are still smooth to the hand. The top ridge does not appear excessive. Hoping I can patch it, and run as is for a while. Oil pressure is good. No smoke.