Hi guys,

Just put some 2nd hand heads on my 272 and I noticed a popping coming from passenger side. I installed new springs rockers and shafts and lapped the valves. Used the valves that came with the heads.

Now I know I have spent all this money rebuilding this engine only to skimp and just throw the heads on hoping they are ok. Not the best idea but now I’m paying for it.

Anyway, I pulled the headers off and looked into the exhaust ports with a torch and cranked the engine (with coil off). I started with no1 cylinder exhaust and found the valve wet and on the compression stroke fuel and air was blowing past the valve.

Do you think it could just be a bad valve or More likely a bad valve seat?


Thanks, Dennis.

56 F100 - 272 Y Block
NSW, Australia.