I bought a GQ 4.2 diesel about 3 years ago. Has an aftermarket turbo. It had a leaking injector pump but it was never enough to worry about.
Recently I had the injector pump rebuilt by Sheppards Diesel and now it smokes when started.
It's a white/blue smoke and when started cold, the engine coughs for about a minute while smoking. After that it seems fine and stops smoking.
But if it sits for more than an hour or so, then the engine cools down enough and it smokes again on starting.
Didn't smoke when starting until the injector pump was rebuilt.
Any suggestions?