This message is marked as Important.

Subject: starter motor R & R.. Author: rv8flyboy : member since September, 2007 : 680 posts Posted on: 2007-12-30 17:26:36

A while ago I bought a parts car with a broken transmission. In the process of trying to start the engine it was noted that the starter sometimes would not engage, but just spin and sometimes it appeared to not retract as evident by the loud whine when the engine would catch.

When we removed the transmission to overhaul the A clutch, my son suggested to remove the starter motor for some R&R. Poor kid even volunteered to take it out for me ;-) I have a funny feeling he hopes to get the parts car drivable enough so he can drive it for a bit. Who says ya can't have dreams.

Anyway, he got the starter out so we did some R&R on it. Found 2 problems. First, the bendix gear has semi rusted to the shaft and second problem was that rust had formed on the plunger that engages the bendix and the electrical contacts inside the solenoid. We found some scoring on the plunger and the inside of the electromagnet which look freshly made.

Here are some pictures of our endeavor. Maybe they will help somebody else fixing their starter

we started by removing the 2 through-bolts and removing the small cover over the shaft at the end.


then we removed the circlip and two washers




next we pulled the metal cap off to reveal the brushes after loosening the strap from the solenoid to the armature.






pulling the nose cone off, gave access to the planetary gear set








The bendix is prevented from sliding off by a metal clip and a ring which clips over the metal clip. I found later that it is recommended that this clip is replaced after it is bend open for removal.








It turned out the bendix and one-way clutch where rather tight on the shaft and required some considerable pulling to get them off the shaft. Matter of fact, I had to use a fiber hamer to tap the assembly off.




cleaned the shaft with some 400 grid sandpaper, removing all the rust. amazing how easily the bendix went back on after the shaft was cleaned.




the plunger was cleaned also as was the inside of the electro magnet
The first pic is the plunger about stuck in the magnet.








time to clean all old dirty grease from the planetary gear set






next in line was a look at the commutator and the brushes. The brushes appeared in very good shape, as was the commutator so all that was done was clean the commutator and the grooves inbetween.








time to do some reassembly. now how the flying fadoodle does one get the brushes to stay in the brush holder so one can slide that armature back in? Tried tying them with dental floss, but that did not work. Finally figured out, the metal brush holders come off, they are held in place by a single hook on the back of the brush holder. tada. remove the brush holders, insert the armature, re-insert the brush holders and Bob's ya uncle.


Note the little hook on the brush holder.





assemble in reverse order, regrease the planetary gear set with some heavy duty grease, and test the starter. If all goes well, you'll be greeted by the sweet whine of the starter spinning and the bendix clicking in and out with snappy movement.



750IL 1990 (9/89) Black, 75K,
750IL 1989 (9/88) Black, 155K

I told my wife, it is not a Boy Toy, is a Man's Machine!!

• starter motor R & R.. (pic) - rv8flyboy 2007-12-30 17:26:36 (3133 views)
  • My starter photo (url) - Patrick C 88 750 160K New piston rings 2007-12-30 23:38:33 (303 views)
    • Re: My starter photo - rv8flyboy 2007-12-30 23:56:48 (181 views)
  • Nice write up ! thanx posting it. (nt) - hvacdude 2007-12-30 18:49:45 (158 views)
    • Excellent write up Thanks for sharing. (nt) - slydon 2007-12-31 07:11:01 (132 views)