Free Starter Advice

I needed a starter for my 650 "test" engine that I bought recently at the wreckers where I work. There were a few more 650 engines going for scrap and one still had a starter motor on it. I removed the starter and tested it on a battery but.....it had kind of a weird noise to it and didn't sound like it should, so I pulled it apart to investigate what was causing the noise.
Here's what I found:

1) NO/NO lubrication left anywhere....assuming Mitsuba put any in it in the first place.
2) The sun gear reduction system was totally dry including the planet gears/pins as well as the outer gear teeth in the housing.
3) The drive end bearing is a single seal ball bearing sealed on the outboard side backed up by a lip seal mounted in the housing on the inboard side. This bearing was totally dry. How it survived this long is beyond me. It had been working itself loose in the housing and had worn the housing somewhat on the interface between the bearing OD and the housing.
4) The small bushing that holds the "dead" end of the armature/rotor in the housing opposite the drive end was also totally dry and the armature shaft was worn somewhat but was still usable. Down inside the housing underneath
the bushing, I could just see a small washer that looked like it was made of leather or hard foam rubber or something similar.
5) The brushes were still serviceable and the commutator was worn very little. There was the usual carbon dust from the brushes in the bottom of the end housing but not a lot.

What I did to try to resurrect the starter after everything was cleaned up in solvent and inspected:

6) lubed the planet gears/shafts on the reduction gear setup as well the big ring gear and sun gear. I used a light synthetic high temp grease for this.
7) the ball bearing had no rough spots and didn't seem excessively loose so I packed it with the same grease as in 6) above and then centre punched 4 spots lightly around the inside of the housing where the bearing fits in an effort to secure the bearing properly.
put a couple of squirts of engine oil into the dead end bushing cavity and on the armature shaft in the hope that the little washer would soak it up and keep everything moist with oil.

I reassembled everything and test-ran it again. It now sounded much quieter.....not as quiet as I would like....but quieter, so it's good to go, IMO. We'll see what happens when it gets put into service on the test engine.
This starter is quite a simple design and is nice to work on since the brushes and brush holders are mounted on main starter housing. This allows you to pull the end covers/housings off without worrying about having to mess with reinstalling the brushes on re-assembly.
Strangely enough (or maybe not....) the FSM does not mention ANYTHING about lubrication of the starter motor anywhere that I could see.
I will/will be pulling the starter motor from my 650C2 the first chance I get and giving IT some lubrication therapy as well. The next chance YOU get to pull yours apart I strongly recommend you do so. As my dear old dad used to say..."Grease and oil are cheaper than shop labour and parts." Words to live by.....

Nice write up. Something to think about with a 30 year old starter! I may pull mine and check it out, Thanks.

ADDITIONAL INFO ON STARTER!!

Hidden away in the "Disassembly-Engine Installed" section of the FSM is a section on starter motor disassembly with a nice exploded view of the starter AND one!! little line about lubrication:

Quote:

3. Apply a high temperature grease to the planet pinions #19 and internal gear #17.

End Quote

Not a peep about the drive end ball bearing OR the dead end bushing!!!
And why the hell wouldn't they put all this nice info in the section on "Maintenance-Electrical" where a normal person would look for such stuff ???
Sometimes the thought processes of the Oriental mind elude me completely.....:S

McMaster Carr used to carry a high temp grease that was listed as robotics grease. had a tacky quality to it so that it didn't sling off. I've used it on industrial packaging machines, and it is really good stuff. Something to think about for those pinions as it won't sling off so easily.

Your notes on rebuilding or goign thru the starter just added to the list fo stuff to rebuild on both my bikes...lol...thanks for the additions....lol!

Doc