My starter was dragging and making noise. I replaced the armature and it would not turn at all. Eventually I found it was dragging on the bushing in the front end housing. The shoulder beyond the end of the shaft (on the left) was .040 closer than the previous armature (on the right). I counter-bored the bushing a little at a time and after a few tries it turned freely like it should. Has anyone else noticed a difference here before.
Also what is the little groove for? It looks like a small ring of felt or o-ring would help seal in oil but have never heard any mention of this before.
Also, while I am talking starters, Friction tape does not work well for wrapping frayed wires if they get hot or oily. I was pretty proud of this fix a few months ago but it is a sticky mess now.
Richard, did you check the length of the other end of the shafts? Or the overall length of the shafts?
It may be that one of the shafts was pushed further into the armature core than the other one.
Or maybe the core has shifted on the shaft?
Or maybe I'm off base here.
I didn't think to measure anything else. The starter is in the car and working fine now so I am happy. I was just surprised that they were not as interchangeable as I had expected.
I did tap very hard on the shaft with a leather hammer but could see no movement.
Thanks for the ideas Ken.
Did you fix the post connector while you had it apart? This is a failure waiting to happen. It looks like the left side is already cracked.
Ken K. Thanks for your concern. That is my gobey solder repair. It was broken but works fine today. That picture was taken a year ago and it didn't look like a problem yesterday. I'll look closer at it next time. Hopefully several years from now.
Good catch though. It will give me something to worry about. :0)