This is a 53 1/2 ton, all original. The 216 engine has always smoked some on startup and burns oil. After a couple hundred miles, the #6 plug fouls but all the other plugs are nice and clean and look good. Recently I installed Fenton headers. Now the blue smoke comes only from the right exhaust pipe. Also, a fine spray of dirty oil or oil and gas comes out of the right exhaust on startup and at idle. When the engine is cold, it occasionally backfires from the exhaust...not big bangs, just several small pops, like maybe raw gas is collecting in the pipe and igniting.
Oil pressure at the dash gauge is normal for these engines. I don't have a compression gauge, but I used a vacuum gauge and the vacuum seems steady at around 20, and the other vacuum tests don't seem to show anything wrong. It looks like the #6 cylinder has a problem. Could it be that the valves are sticking, or maybe the valve seals are shot and oil is leaking into the combustion chamber, and burning, and the gas isn't completely burned on ignition? What should I check? Thanks
