some of you might remember my post couple weeks ago about my alternator and the troubles with this part.



anyways , I figured one of the "things" broke off and since I had two more alternators I took them apart, compared all the parts and made sure they were the same. Then I replaced the part in the pic with the same part from another alternator.

painted the case , both the rear one and front, making sure that there was nothing in the cases that could have been damaged by the paint (that was my reason for even taking the thing apart).

I bolt everthing back up as it was before (I took pictures while dismantling it so I would know what it looked like before).

put it in the car

started the car , let it run

I hear squeling sounds , ok , probably the belt. No big deal... (I'm 99% sure that it was one of the belts).

anyway , after about 10 minutes I start to smell smoke , so I look at the alternator (car was just running in the driveway, I didn't drive it anywhere), and I see smoke coming out of the alternator.

hmm , so I touch it and the thing is HOT !!! like really really HOT !!!

WHY ???

I took the thing apart again and nothing is broken inside, nothing is melted, nothing seems to be out of place.

here's my theory

when I painted the case I covered the bearing inside the rear part of the case. but I never added any grease to it afterwards, so is it possible that there wasn't enough grease in there and that heated up the case ??? if that's possible, should I use the other rear case from the second alternator or is the bearing still fine ???

I know it would be easier to buy a new one , and I've done it couple times before , but no way in hell I'm going to give up after all this work lol , plus car won't be driveable for a while anyway so I'm in no hurry...

please help me fix this !

thank you.

 

i tihnk you'd be ahead using the case halfs with known good bearings, or replacing the bearings in the case you have. if the parts store doesn't have bearings for you try Bearings Inc.

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ICON Motorsports

1st & 3rd

 

That "thing" is the brush holder. It's about $4 or $5 for a new one.

The reason your alternator got hot is probably because your battery was completely drained and it was working its little butt off to charge it back up. The current flowing in the alternator heats it up. It's possible however that the diode bridge (the big aluminum thing with the fins in it, that's all the way down in the bottom of the case rear) is bad; if so, the alt will get hot whether the car is running or not, and will rapidly drain the batt.

A new front bearing is a universal bearing, you can get it anywhere that sells bearings, from a parts store to a hardware store; it's a 6203, can often be had for less than $2.

The rear bearing is specific to alternators and is therefore expensive. Definitely grease it.

If the alt is charging the battery, and the bearings themselves aren't making noise, I'd leave it alone.

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"So many Mustangs, so little time..."
ICON Motorsports

 

thank you !

I think I'll buy a whole new alternator overhaul kit and replace everything inside of it , that way I know the parts are good and will still have the pleasure of doing it myself instead of buying a new crappy alternator