Alternator cooked, seized, cranks but does not start

I'm in no hurry here because there's plenty more to do, but my alternator played the part of temporary engine support to get me out of the woods. The ground stud boss broke and wedged into the regulator in the back of the case, which made no difference until I jumped it a couple of times. It didn't like that. After cutting out a few times, I smelled the generous liberation of smoke and it died.

Today, I got around to pulling it, and hadn't realized it was seized. Looking at it, it certainly burned, but would that really kill the ignition? Is there a chance it took out something else like the coil or ECM?

If it seized it could put enough load on the belt to kill it and not restart. Try starting with the belt off?

I have the oil filter off at present to drill the broken bolts for the engine mount in the side of the block and I'll be putting it back together with another alternator. I just figured I'd ask for speculation in the meantime.

Otherwise, it would have broke the belt. Been there before.

Never mind, it was the ENG CTRL 2 fuse in the PDC.

Overland said:

I have the oil filter off at present to drill the broken bolts for the engine mount in the side of the block and I'll be putting it back together with another alternator. I just figured I'd ask for speculation in the meantime.

Otherwise, it would have broke the belt. Been there before.

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Maybe. But I've seen many cars with siezed alternators or ac compressors or whatever that won't start but never broke a belt. Good you had an easy fix tho.

I have had numerous reman alternators where the bearing in the rear of the alternator housing goes bad/dry and essentially squeals and eventually seizes.

I lost the passenger motor mount bracket bolts in the block on a particularly rough trail. Zip tied a log to the frame and put the alternator down on that to get back to pavement. It busted the ground stud and started making noise within a hundred yards, having crammed it into the back of the case. Trail was mostly steep rock gardens with big steps off camber.

Pretty sure it was the original alternator. I'll rebuild another original alternator to replace it, probably have a couple of them around. I'd take a used original over an auto parts store reman any day.

If the alternator smoked, check every fuse first. If it went open loop, the output voltage could have seriously spiked. I have actually seen them take out an ECU, but it is rare.

Also double check the fusible links and see if it boiled out the electrolyte in the battery.

like said check your fuses and fuselink.
look in to new motor mounts and plates like the one's sold by brown dog or sfr.
personally install the SFR units and very very please with them. only a mild amount of vibration felt in the chasy, mostly in gear at rest. But the amount of beaf in the new plates is worth it. They will prevent what you just had to do. they pick upi on 7-8 bolts perside instead of 3-4. and are rebuildable.

old_man said:

If the alternator smoked, check every fuse first. If it went open loop, the output voltage could have seriously spiked. I have actually seen them take out an ECU, but it is rare.

Also double check the fusible links and see if it boiled out the electrolyte in the battery.

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It also took out both 60A MAXI fuses for the alternator circuit. It's all 92 under the hood.