Inside your DB high Torque starter, and why it failed...

[dlnw98]

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.

[bigb56]

There a several threads around on various PSD site about db starters. I too got a bad one, it would not engage completely some of the time and not engage at all at times. db sent me another one, same problems. This led me to believe it was something else, so I replaced the battery cables (all three) and even added a fat grounding cable between the block and one of the starter mounting bolts. I replaced my under dash starter relay. I bypassed the ignition switch. The problem persisted (Both batteries were already brand new.)

Finally I pulled the db out and took it to a local starter shop. They found a couple of things wrong, one being a loose part, seems like he said it was the final drive. They fixed it for $50 and said it was a good starter now and I wouldn't have any more trouble with it. They did say this same starter is commonly available at a lot of places, and it is made in China, which I already knew by the tiny sticker on the bottom. So I don't think it's really anything special, although db does sell them cheap.

It's been about a year now and it's been working fine. I still keep my OEM behind the seat though just in case.

[BrownianHeatingTech]

I just spent $20 on a new plunger, contacts, and spring. ($10 for the parts, and $10 shipping)

I'm going to take it out and rebuild the solenoid, early next week. Looks pretty straightforward, but if anyone knows of any tricks, please let me know...

Currently, it just sticks occasionally, and I have to crawl under there with a small hammer and apply some percussive maintenance. I want to fix it before it gets to the point that it just won't run anymore.

[BrownianHeatingTech]

Well, that was ridiculously easy. Took longer to remove and re-install the starter, than to replace the guts of the solenoid.

[mythreesons]

Can you give us the part numbers and supplier for the parts you bought ? Thanks.

[BrownianHeatingTech]

I called EMS at 800-697-6070 and told them that I had a Denso 228000-8420 starter and what parts I needed, so I never had the part numbers.