can anybody please help me with this. what are some reasons for this and also has anybody had the the same issue?
Alternator getting really hot! Cant even touch
My alternator, for some reason, is getting extremely hot...what could cause this issue?.
I have replaced the battery and played with the tensioner (tightened it)...not sure what else to do.
I have replaced the battery and played with the tensioner (tightened it)...not sure what else to do.
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GUESSING, too much output load or bad bearings.
Check the voltage output at the battery.
How about ambient too hot under the hood?
Check the voltage output at the battery.
How about ambient too hot under the hood?
brand new battery just installed last night trying to fix the problem. that wasnt it... the car has no hood on it right now. i did ground the battery wire to the alternator bracket. the bracket is also painted black by me. could this be the problem since the wire is not grounded to a fresh clean metal surface?
You may have answered part of your own question ?
i have not tried to find another ground location yet. do you think this could be the issue? just need somebodies skilled opinion before i do anything. thats allYou may have answered part of your own question ?
Alternator needs a good ground path back to the battery. Make sure your ground cable and alt mount have a good path to the battery. Ditto on the pos cable as well.
Then you can move on to the mechanical side if it is still burning hot (they do run warm though).
Then you can move on to the mechanical side if it is still burning hot (they do run warm though).
Get a DC meter and check voltage input and output ,could be. Voltage regulator problem
Could also be bad diodes in the alternator too. Take it off and have it tested..
I had the same problem on a different vehicle and it was the wires were reversed switched them around and all good now.
Was a GM motor on a boat.
Was a GM motor on a boat.
High voltage, bad diode, improper alt fan, bad bearing , defective heat sink ,high voltage drop accross alt power wire or ground wire . A few places to check
alternator fan, now why didn't I think of that?
1. measure voltage. if above 14.8ish, regulator is bad, and is running alternator wide open, resulting in excessive heat. Will very soon ruin your "brand new battery".
2. if voltage is below 12.6 when running, suspect bad diode
3. If voltage is between 13.2 and 14.8, disconnect exciter wire. Run alternator. If unit STILL gets hot, suspect bad bearing. If unit stays cool and HAS a fan on it, recheck alternator and other system grounds.
Just some diagnosis to try.
Suspect a bad regulator myself.
2. if voltage is below 12.6 when running, suspect bad diode
3. If voltage is between 13.2 and 14.8, disconnect exciter wire. Run alternator. If unit STILL gets hot, suspect bad bearing. If unit stays cool and HAS a fan on it, recheck alternator and other system grounds.
Just some diagnosis to try.
Suspect a bad regulator myself.
i was messing with the fan belt and pushing it softly. i noticed the alt fan made a slight clicking noise when i pushed. would that be the sound of a bad bearing or bad fan on alternator?
Like I said, run it with the exciter and load wires disconnected and see if it gets hot purely from mechanical rotation. That'll answer your question.
Make sure the vents are not blocked. You may need to get a higher current rated alt.
Post some pictures. There may be clues there as well.
I smoked an internally-regulated alternator on an externally-regulated vehicle, because I connected the two wires at the alternator according to GM spec, but used the damned MAD Electrical wiring diagram at the external-regulator connector.I had the same problem on a different vehicle and it was the wires were reversed switched them around and all good now.
Was a GM motor on a boat.
Got so wound-up about MAD's mistake that I built my own wiring diagram, which actually uses the correct color-coded wires in the GM-intended locations.
Once again, it is dirt simple to wire up a 12SI 3 wire alternator to an earlier vehicle.
Mount 12SI internally regulated alternator in place, install the large gauge battery to alternator cable, removed from the old alternator, onto the new alternator BATT terminal. Build and install a bridge wire, 14 gauge, one ring terminal on one end, one .250 wide flat female blade terminal on the other, from that large BATT term on the new 12SI alternator, to the number 2 terminal on the rear of the new alternator.
If you have either a volt meter, or ammeter, you are done, finished, works like stock.
If you have a charge light, then, use a wire length to connect the number 4 wire from the old remote mounted regulator connector, to the number 1 terminal on the alternator, the light will work as stock, done, finished.
DIRT SIMPLE, I'VE BEEN DOING IT THIS WAY FOR OVER 25 YEARS, NO PROBLEMS. This is the way GM have done/does it as well.
All this hooey about connecting all sorts of wires to the old connector is just that, useless hooey. Do the connections at the alternator, NOT AT THE OLD REGULATOR CONNECTOR, simplify the whole mess, for goodness sake.
If anyone wants diagrams of how to do it the right way, PM me on this site, and furnish me a real email address to send same to, and I will be happy to forward the diagrams to you.
I have 12SI alternators with this wire up on just about every make and model vehicle there is to play with, with NO PROBLEMS. My neighbor's Continental fork lift even has one I did for it, NO PROBLEMS in over 15 years of constant operation.
Mount 12SI internally regulated alternator in place, install the large gauge battery to alternator cable, removed from the old alternator, onto the new alternator BATT terminal. Build and install a bridge wire, 14 gauge, one ring terminal on one end, one .250 wide flat female blade terminal on the other, from that large BATT term on the new 12SI alternator, to the number 2 terminal on the rear of the new alternator.
If you have either a volt meter, or ammeter, you are done, finished, works like stock.
If you have a charge light, then, use a wire length to connect the number 4 wire from the old remote mounted regulator connector, to the number 1 terminal on the alternator, the light will work as stock, done, finished.
DIRT SIMPLE, I'VE BEEN DOING IT THIS WAY FOR OVER 25 YEARS, NO PROBLEMS. This is the way GM have done/does it as well.
All this hooey about connecting all sorts of wires to the old connector is just that, useless hooey. Do the connections at the alternator, NOT AT THE OLD REGULATOR CONNECTOR, simplify the whole mess, for goodness sake.
If anyone wants diagrams of how to do it the right way, PM me on this site, and furnish me a real email address to send same to, and I will be happy to forward the diagrams to you.
I have 12SI alternators with this wire up on just about every make and model vehicle there is to play with, with NO PROBLEMS. My neighbor's Continental fork lift even has one I did for it, NO PROBLEMS in over 15 years of constant operation.
My altornator for some reason is getting extremely hot...what could cause this issue?. I have replaced the battery ,,played with the tensioner (tightened it)...not sure what else to do.
1 - 20 of 27 Posts
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