First some background-
Installed a brand new DB high torque starter in my 2000 7.3 this past January. That's right, about four months ago. Truck does not get driven every day. Up until last Sunday, I would guess less than 50 starts on this starter. Went out to start it Sunday, and nothing. I could hear the solenoid on the RF fender clicking, so I verified everything at the starter itself. Battery cable at starter had 12v continuous, which it is supposed to. Also verified that the solenoid wire at the starter was getting 12v when the key was turned to the "start" position- it was. Clearly, the new DB starter just crapped the bed, and it appeared to be a solenoid issue at the starter itself.
So I took it out. And I ripped into the starter to see what I could see.
Picture 1- Rear of starter laying on my workbench.
Pulled the rear cover off the solenoid:
Close up of the contacts, plunger and round copper contact on the plunger:
Plunger removed from coil:
And here, finally, is the problem. The plunger shaft itself began to spall terribly. It obviously was not hardened enough, and in only 50 starts (estimated) the shaft of the plunger began to feel like 80 grit sandpaper. When I would push the plunger into the coil with my finger, the friction was unreal. No wonder it crapped out- the coil couldn't pull the plunger inside anymore due to the friction.
I did talk to Robert at DB electrical about a replacement. No issues there. He did admit that they had a batch of starters out there with bad solenoids. You think???
Supposedly, they have fixed the problem. I'm hoping that the supplier hired a metallurgist that knows how to harden metal correctly for the intended use...
I'll take them at their word and give them one more shot- I really liked the performance of the DB starter. I have the original OEM starter back in my truck temporarily, and have forgotten how insane the DB spins my truck over compared to stock.