I have a bobcat 743 with a kubota diesel engine. Today out of the blue the engine lost power, ran rough, like it was loaded up and stalled. I had recently filled up with heating oil (off road fuel) fuel so thinking it might be the fuel, I Changed fuel filter, drained and washed out fuel tank, replaced fuel lines in tank, filled up with new diesel, bled the air out of the system. Got it running, will run at an idle, but when idled up, it starts to run rough and will stall. It will not restart after, once it sits for a few minutes, it will restart, idles alittle but then the same symptoms occur. I don't know if I got ALL the pink fuel out of the system, but I have a hard time thinking it is the fuel pump or injectors. Any suggestions please.