Stuck or burnt valve?

I'm wondering if the "popping" isn't something to do with fuel injection pump/injector performance. I would cut out each cylinder in turn by loosening the fuel line connection at the injectors. That will tell you which cylinder and once you know that, you can swap injectors, pumps. inspect valve clearances etc to further diagnose the problem.

:confused2:Thank you guys for the info. Forgot to mention that the motor does not smoke in the least little way. I bled did the injector lines at the pump but it didn't have any effect. I will pull valve covers off and see if all valves are moving and are connected. After that I will adjust the valves as I believe this to be done while the engine is hot. After that I guess the heads need to come off to see if there is a problem. Thanks, Steve

Take the injector lines off one at a time at the pumps and see if compression is coming back through the injector to the pumps while it is running. sounds like a bad nozzle. a valve would sound more like a lisp sound at the exhaust pipe.

That's a really good idea! I will check that out and let you know. Won't be able to get at it until about a month. THANKS....STEVE

You can also touch the exhaust manifold when its running and check all exhaust outlets to see if any are staying cold.