1992 D250 Starting Issue

Hey all,

I'm new to this forum, I just inherited an automatic, intercooled D250 a few months ago and I love my truck. I daily drive it and it always started in less than a second after cranking the engine.

The other morning I went to work, started up just fine. I got back in my truck about 20 minutes after getting to work and it made a horrible grinding noise prior to starting. I freaked out, shut it off immediately and I couldn't get it started again without pumping the throttle (the grinding happened again) and it took even longer to start then before, about 5 seconds.

I immediately went and bought a new starter (left the truck running while I went it to buy it) and installed it as soon as I could get back in the driveway. The first crank after getting the new starter in was flawless, but I warmed up the truck, shut it off, tried to restart it and the problem is still occurring.

I googled and searched forums desperately for an answer, and I read that heat soak, a bad starter, and a bad flywheel might all be culprits. But what confuses me is how sudden everything was. The truck was running perfectly one night, and the next morning it's having trouble starting at all, much less without that terrible grinding.

Truck runs perfectly after start, any help would be much appreciated.

Thanks