8N starter questions

[rossow (mn)]

Starter issue with 1951 8N (12v conversion): Last summer the starter would spin but the original Bendix wouldn't engage. I put in a new-style Bendix and the tractor started up fine, but the next day it was the old story -- spin and whir but not engage. I finished the summer by crank-starting it and put it away for the winter. I decided to tackle it again today. The ring gear is tight on the flywheel, no missing or bad teeth. Electrical connections are bright and tight. Battery is strong. Tried two different sets of battery cables. Starter-to-housing mating surfaces are shiny. I pulled the starter and removed the Bendix. It looks brand-new (which it is). It slides freely on the long starter shaft, which is shiny, clean and dry. My questions: (1) How freely should the starter shaft turn? I can grip it between thumb and forefinger and turn it fairly easily. I assume it should have some drag from the brushes. (2) Also, can I hook the starter up some way on the bench to see if it spins with the Bendix removed? If so, how do I connect to the solenoid to do so? I don't want to fry something unnecessarily. (3) Maybe I simply got a defective new Bendix? If bad comes to worse, I'll pull a starter from one of my other 8Ns, install it on the '51 and try the malfunctioning one on the other tractor, but I'd like to avoid that hassle if I can. Or maybe I'll take the starter to a shop to have it checked and rebuilt if needed. At this point, I'll appreciate any advice.

 

[ratface]

did you try rocking it back and forth in third gear and then see if the starter engages then? I replaced my ring gear last year and they only wear in a couple of spots but the rest of the ring gear would look fine. You could shine a flashlight in there with the starter removed and check out the entire ring gear by rotating the engine either by the front through the hole in the grill with along extension and socket or remove the plugs and turn the fan.