Non Caterpillar question (IH TD-6)

Hello everyone,

I realize this would probably be best posted on Redpower, but alas I am having technical difficulties doing so. 

I have a 1949 TD-6 (Ser# TDBK 21303) that is/was having issues with the starter not engaging properly. Upon removal of the starter, I discovered some mild wear on the forward face of the ring gear, however a substantial portion of starter drive gear was worn away. I am send the starter out for rebuild, am curious if the starter gear is the correct tooth count (13) based on the wear. 

For context, the starter motor appears to spin properly and when everything engages “properly”, it turns the motor as expected. With that said, it’s about a 1:75 ratio of that happening. 

Any thoughts or insight are/is much appreciated. 

thanks much,
Breadler