your starter drive is not engaging all the way...look for worn teeth on the drive....also, direct connect the starter to a 12 volt supply (battery with jumper cables works) and see if the starter drive (bendix) is kicking all the way out.....
While its out take a look at the flywheel teeth too.
Were the bolts loose on the starter when you took it out?
Make sure the starter gear when all the way out is engaged on the shaft....do this with NO power to it
2013 WRANGLER SPORT 2 DR., V-6 ,AUTO,HARD TOP
(Sold)1994 Jeep Wrangler 2.5L, Bestop top
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Ok, the flywheel looks good..so does the Bendix teeth. I applied 12 volt source and the bendix pops out like I guess it should. Strong and solid. But no turning,even when I put a jumper on to the starter positive side the bendix did not turn...shouldn't it? Its a motor..the bendix engages,but does not turn
So, you are saying that the gear moves out but the gear does not turn. Replace the bendix if you know how, the starter is not that expensive rebuilt. I just put one in for $70.00 completely rebuilt. Works like a champ.
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You need to put 12 volts on both terminals of the starter at the same time!! Clip your positive jumper cable to both or short with a screwdriver or piece of wire, clip your negative cable to the starter housing and hang on to the starter.