Stiegg

So I'm workin on my alternator and everything is off minus the positive terminal for it and the last nut will not break free I've used a 1/4 hex impact and about all the ratchets that fit its a 13mm please someone help me out here need it fixed

Heguli

That is so badly rusted, that easiest and cleaniest way to remove it would be a metal nut splitter.

juanmor40

The space is very tight around there. Is it enough for a Dremel, and cut across two nut faces to weaken the nut?

chassis

Nut splitter
Dremel
Air chisel --> secret weapon. I used an air chisel to put the beatdown on a rusted/seized front axle fill plug on a 4Runner. Place the chisel blade mostly perpendicular to a nut face, offset from the bolt axis, Give the chisel some juice and either turn the screw or slice it into pieces.

ot1

an air chisel will damage the battery internally!

that nut is thin, center punch a nut face, then drill an 1/8” hole, then 1/4”, you maybe will need jobber length bits to clear the drill chuck. 1/4” should cut thru top and bottom of nut, if not go 5/16” or…

chassis

This is an alternator, not a battery, agree? An impact has already been used. An air chisel is no different, it simply applies the blows in a different orientation and more concentrated in the desired direction for the nut to move.