Mep-003 runs but starts smoking heavily and dies

I have a mep-003 and it will start up and run strong. After about 5 minutes it starts to not as run as strong and starts smoking pretty with very black heavy smoke. It will lose power and die shortly thereafter and wont restart. Its almost like it is burning up the engine oil. After is rest a while, it will usually start back up.

I didnt see how this engine breathes and initially thought it was pumping oil into the intake and burning that but didnt see any breather lines running to the intake.

The air does not seem to be restricted and does the same with no air filter in place.

I have replaced the injection pump with a rebuilt unit, flushed out the fuel tank, and installed all new filters. The engine is showing 400 hours and looks real good. It had been sitting for a while prior.

Do you have any ideas?

thanks!

Maybe clogged return line

I blew out the lines when I cleaned out the gas tank and did the filters but will certainly double check it. thanks!

I once had a problem like this with a 60 KW. The flexible hose from the air filter to the air intake manifold, collapsed INSIDE. The outer covering, did not collapse. But the inside did. The hose is made up of an outer covering, a wire coil, (spring if you will) and and inner covering. looked normal from the outside, but choked off air to the engine. This was a killer problem to solve!