Originally Posted by DAYCLONA
Originally Posted by MoparsnMissiles
Originally Posted by eightlitermopar
1971 Plymouth roadrunner, 383 engine. Newer stock style alternator bought and has been sitting for 18-24 months while I have been getting it up and running again.


The alternator spins free by hand with no belt tension. The belt tightened and it is locked solid.

Started the car and the belt was spinning but alternator would not turn. It squealed and smoked the belt.

Took off the very hot belt and the alternator spun with no problems by hand again............

............ but I was wondering if anyone has ever seen anything like this before. It's a first for me.

Thanks
eightlitermopar



Yes, I've seen this very problem. Its quit simple but not obvious to everyone.

When you have the belt off, all the mounting bolts are loose and the alternator spins normally.

When you tighten the belt, you now have tightened the mounting bolts to hold the alternator in place and keep the belt tight.


Well, IF YOU DON'T HAVE ALL THE CORRECT SPACERS between the ears of the alternator and between the alternator and the head, you are now squeezing the ALTERNATOR CASE together enough that it locks up the rotor of the alternator.

I'd put money on the fact that you are missing one or more of the correct factory spacers for the alternator bolts.






Also the single locking bolt on the adjustment arm, if it's too long it will hit the vanes on the rotor and lock up the alt....DAMHIK



It sure will, thanks, I forgot about that little possibility. Done that in the past also.

Last edited by MoparsnMissiles; 05/02/21 10:57 PM.