Just went to put a new alternator in my 86 toyota pickup 22R, Apparently the one i pulled off was for an 84 tho and the hook up for it was spliced into the wiring harness, It looks legit tho. so i have both plugs for a 84 and 86 style alternator in my truck but the 86 one wouldnt mount up because someone mounted up an 84 alternator, to i returned the 86 alternator and they gave me one for an 84 that would mount up... so.... two bolts later and after plugging in the square plug with the three wires and the pos to the post i put my terminal back to my dead battery and hook up jumper cables to start my truck and let charge.... But as soon as i connected to power the black wire in the spliced harness started burning up till where is connects to the original harness until disconnected from power. Its possible that when i tightened the pos to the post it may have been touching the other plug but i dont thinks so... have no power to truck even when hooked up to cables i see no dash clock no lights nothing.... This is a great running truck and was running great with a jump start before i changed tha alternator, the black wire is exposed now because of burnage. If anyone has any insight it would be much appreciated... thanks .

The 84 alternators used an external voltage regulator, 85 and up used an internal voltage regulator, so it seems that someone some how rigged up an 84 alternator to work on your truck. I would buy the right alternator and find the correct mounting bracket and put it back the way it should be. And also fix the wiring.

x 2. The difference in the mounting brackets is that one lines up where the ears are on the inside, and the other mounts them on the outside.

BTW myYota, I grew up on the South Fork.

so your saying the 84 alternators external voltage regulator makes it non compatable with my 86 truck even if the wiring is the same execpt the shape of the plug? would this be the reason for the burning wire and no dash lights no nuthin? I was thinkin theres somthin thats shorted out or not grounded and didnt know until fresh alt was put in... still stumped tho.

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