F 20 starter problem

[SDE]

It is my opinion that the mica between the commutator segments needs to be reduced. How can I do this and what tool should I use?
TY
SDE

 

[used red MN]

It is my opinion that the mica between the commutator segments needs to be reduced. How can I do this and what tool should I use?
TY
SDE

Usually not a problem on a starter, more important on a generator. Here is how it is done correctly. Undercutting a generator commutator

 

[matthies]

In college they had use a hacksaw blade. Cut the end back an inch and angle it to get right up and close.

 

[SDE]

Usually not a problem on a starter, more important on a generator. Here is how it is done correctly. Undercutting a generator commutator

TY for the link. I found it to be very interesting.

 

[SDE]

In college they had use a hacksaw blade. Cut the end back an inch and angle it to get right up and close.

I will try the hack saw method and then hope the starter works.

 

[used red MN]

I will try the hack saw method and then hope the starter works.

Some will cringe on here but I am not sure how familiar you are with Delco automotive starters from around the 70s and 80s had a stamped steel back plate with the rear bushing in it. An old mechanic showed me how to the clamp the end plate in a vise. Then chuck the drive end of the armature in a drill. Stick commutator end in the rear bearing clamped in the vise. Spin it up and clean up the commutator with a mill nnalert file. Hit it with a little emery tape and they were good to go. Rebuilt many that way always worked fine.