I have a 1989 Ford F250 7.3 IDI that has 235k miles, Automatic transmission, runs ok, will not start after I had it running and it cools off even a little. Have to wait until it cools completely or use starting fluid. My question is about power. Runs well about even without a load it's a gutless wonder. Had it about 6 months haven't done anything to it yet but looking to find out what I have to work one to improve the power. Been working on gas engines for 40+ years but this is my first diesel. So I'm not stupid, just need to learn diesel systems and troubleshooting. Towed my 30' Shasta and was an experience in fear I don't want to repeat. Compared to my 71 Winnebago with a 403 this diesel is way under powered. Bought it thinking it would have alot more power than it does. Starts well, runs without alot of smoke just no power. Never got over 50 mph towing and that took a long time to get there. Just will not pull any type of hill, like 20 mph going up an on ramp of the freeway. Even without a load you have to floor in to get up to 55 mph and looses that as soon as you start a small hill. Was told the original owner was a truck driver so it was taken care of. Mostly looking for information on the things I need to work on to try and get some power back. Should I replace fuel lines, fuel pressure or something else that may be causing the problem. Thank you for your any input and information on procedures to troubleshoot the problem.

 

I forgot to add that it sat for a long time and I purchased a manual controller for the glow plugs. But haven't installed it yet. The ohms read .4 to .5 across all the glow plugs. The kit I bought has a new controller as well a momentary switch. Haven't heard from other owners if this will help with the glow plug problem or if anyone else has tried this fix.

 

The injector pump on top of the motor could be weak and the float in it is most likely wore out and the o rings on top of the injectors are probably cracked I would recommend getting the pump redone with a little more power in advance the timing a little if you have the equipment and redo the return line on top of the injectors. The idi's have tons of power for pulling just not much horse power. My farther own a 92 idi and I own a 95 di we both pull the same size trailers and the only deference is I can take of faster and do hills better bc of the turbo but other the that he pulls the same 10000 lbs I do all through tx