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Alternator issue? Hot to touch? and multimeter ?

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71 Monte. Ive been running an internal voltage regulator for years. No external Regulator. Had existing alternator rebuilt and new pully put on. I also changed the 2 prong plug as the old wouldn't clip in.  Everything ran fine.  Car - engine was cold and I was checking the belt and put my hand on the alternator and it was hot.  Not warm, hot and motor was cold. I unplugged the two wire plug came out the next morning alternator is cold.  I plugged back in the two wire plug. Let it sit car wasn't started /run at all.  I  came out 30 to 45 minutes later and the alternator was warm , generating heat!! 

   Key off. Using multimeter set at 20. The white wire in clip no voltage. The blue/red wire 15.40. The single post Battery on alternator 15.53. The Battery itself 15.65.  Either I wired the two prong clip wrong. FLIPPED THE WIRES. Or its an issue with the Alternator.   I thought it would be like 12.5 with car off at the Alternator and 12.6 at battery?  Am I using the multimeter correctly ?


BAT TERM Back of alternator.jpg

2 Prong plug blue-red wire.jpg

Alternator plug.jpg

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My bad. Battery in Multimeter needed changed... Checked agian


Alternator - White wire on two wire plug  =  00.2/00.4 Key off

Alternator - White wire on two wire plug = 11.79           Key on 

Alternator - Blue/White wire on two wire plug = 11.84

Alternator - Terminal with Red wire = 11.84  

Battery  - 11.82

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I cant remember when I removed the voltage regulator and added the Jumper to use the Alternator with the internal voltage regulator. If I had used a diode.  When I changed the plug I didn't use a diode. And of course , I can't find the old one I cut out to check...     So I wonder if that is the reason it gets hot when car is off? Or if its just me. 



Diaode needed ?.jpg

Voltage reg Jumper.jpg

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From looking at the wiring schematic I think your wires are jumped incorrectly..from the schematic it should be blue to brown, not blue to red... also should be white to red, not white to brown... Ron

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