white smoke at idle?

My D6 9U to puts up puffs of white smoke at idle, even after working hard for a few hours? I can see it at start up, not warmed up yet, but after working hard and temp is up to normal, still smokes if throttle too low? Thank you, Tom

Sounds like the injector timing could be a bit retarded.
First thing to do is adjust the pump lifter heights as per your Serviceman's Reference Book.

You might also have some weak injectors.

I think I would start by loosening each injection line in turn and see if you can eliminate the smoke by making each cylinder misfire. Once you know which ones are doing it, you could move those injectors to a cylinder that was not smoking and see if the problem moves with the injector valve or stays in the same cylinder.

Aftermarket injection "valves" as CAT calls them are around $30 each so it doesn't cost a lot to replace them but you may be replacing good injectors in cylinders that have low compression or are fed by injection pumps that are leaking or operated by camshaft lobes that are worn etc. By moving some stuff around you can rule out some problems pretty simply.

Will take a look at the lifter height since that is what it looks like the most. thanks again, Tom