91 F150 starter troubles.
 

I have a 91 f150 with the 300-6 with a 4 spd tranny. I've been having trouble with my starter lately, i've put about 5 in it within the past few weeks. What happens is it will start when i put the new one in a few times, then it just grinds on the flywheel and doesn't catch. The truck has a new flywheel in it, I just replaced it this past weekend. What i'm wondering is what would be causing it to keep doing this. Is it going too far back and only catching the back side of the flywheel, or could it be getting too much juice to the starter and burning up the internal parts. Any help would be much appreciated.

It sounds like you were having the problem before you changed the flywheel; is this why you changed the flywheel?

Have you been getting the starter bench tested before replacing them?

I changed the flywheel because it was missing teeth in some spots. Yes, I was having that problem before I changed it. I have had all the starters tested before I bought them. The one that I just put in it was tested and it worked good on the test. Could it be possible the starters they've been giving me don't have enough torque to turn the engine over?

update
 

Just a little bump on the thread. I don't know how many of you guys know this, but in 91 (not sure about other years) they made starters with a 9 tooth and a 10 tooth gear. I kept getting starters with the 9 tooth, so I took it to a local guy and he put a 10 tooth gear on it and it starts quiet with no problems.

Good work!