Rebuilding an m50 starter

[Mendozart]

Has anyone attempted to rebuild one of these? Mine is starting to act up and I'm going to be taking my car down for some extended service. If so, what parts are needed?

[Blitzkrieg Bob]

Has anyone attempted to rebuild one of these? Mine is starting to act up and I'm going to be taking my car down for some extended service. If so, what parts are needed?

Rebuilt a few.

Several things can go wrong

What is happening?

[fin]

I'll let Blitzkreig handle the diagnostics.

I've rebuilt one starter a few times in the same day. Turned out not to be a starter problem at all, but a loose connection at the terminal block.

The big take-away from my starter rebuilding marathon was the big difference made by loading the planetary gears with grease. The RPM's when cranking over were much higher and it sounded so much better.

I used to have a very good Bosch starter overhaul page bookmarked, but lost it when switching to a new computer. It was on a VW forum I believe, but it doesn't come up when I google for it.

I didn't have Solenoid problems, so I can't help you there.

Best of luck,

Fin

[Mendozart]

Rebuilt a few.

Several things can go wrong

What is happening?
It doesn't seem to engage every time. Sometimes you'll hear it just start to crank, then it quits. The battery is fine. It looks like I'm going to be pulling the head off my car soon, so this will be the perfect time to take out the starter, what with the intake out of the way.

[pingu]

Try:

http://www.rangerovers.net/repairdetails/electrical/boschaltrepair.htm

[gale]

My son's e34 535i starter crapped out last year. The internal plasic bracket that holds the planetary gears self-destructed. I bought a rebuilt (junk!) one from Checker's (big mistake!) but they were the only ones that had on in stock and I needed it in a hurry.

The replacement starter did the same thing yours is doing, intermittent clicking/no start. It took several iterations of removal & testing and I finally discovered the threads in the endcap were stripped:

http://www.nmia.com/~dgnrg/starter1.jpg

http://www.nmia.com/~dgnrg/starter2.jpg

The 2 screws near the center bearing cap make the ground connection for the brushes on the underside. I drilled them out & tapped them the next size over, cleaned the contact surfaces and tightened them and it's been working fine all this past year.

To do it over again, I would have kept the original starter and got a junker from U-pull-it to turn in for the core & used the Checker rebuilt starter for parts fo fix the original. Then again, to do it over I'd get a Bosch rebuild from BMA, etc.

[Blitzkrieg Bob]

It doesn't seem to engage every time. Sometimes you'll hear it just start to crank, then it quits. The battery is fine. It looks like I'm going to be pulling the head off my car soon, so this will be the perfect time to take out the starter, what with the intake out of the way.

Test the solinoid by jumpimg the poles on the back...if it cranks good, then chase it back to the electrical.

Or better yet, just pull it and bench test it