My 99 E150 4.6 starter spins but does not turn the flywheel. I removed the starter and had it tested at autozone. It tested "good". Thinking maybe it was a connection I took a jumper cable from battery pos. to the starter. Same thing, not turning flywheel. I can't feel any broken teeth on the flywheel through the starter opening. Any ideas.
Thanks,

 

When you engage the starter, does the pinion gear kick out? I've never watched them test a starter at autozone. Not only should the starter spin under load, the pinion gear should kick out. If the pinion gear kicks out and hits the flywheel, but the teeth don't mesh, it makes a terrible noise, grinding noise. Do you hear a grinding noise, when you engage the starter?

 

Thanks for the help, its fixed. The starter was bad all along. Autozones test is in a covered machine, power only, no load. It tested good to current and voltage. I tested it at home the old fashoned way, kneeling on it and hitting it with a jumper cable. The motor turned just fine but the gear did not come out. Installed new starter and off I went.
Thanks again,
Bill