82yotacrawler

Hi everyone, new to this forum, but will be here alot now. Just picked up an 82 longbox 4x4 that im going to build into a cheap mudder toy. It has a rebuilt 21r with a 20r head. Not sure if this is a good or bad thing but it seems to have decent power. It has a lockright locker in the front and the rear is welded. Sitting on 31's atm but will end up on 35's when im done.

Anyways its got some electrical gremlins. The guy that had it before me replaced the alternator and ever since then its been burning up fuel pumps. So i got it home, put on a new fuel pump and started it to find 17-18 volts at the battery. So i shut it down and bought a new voltage regulator. Started it back up and same thing 17-18 volts. This is when I peeled back the wiring looms and took a look at my nightmare. Someone has hacked it up pretty good. I checked continuity and all the alt to voltage reg wires test good. My biggest concern is a large black wire on the harness to the altenator that is cut on the alt side of the harness. The other half tests to be a ground but it not hooked to anything. Anyone know where that wire is supposed to go? Will an 84-85 internally regulated alt bolt on?

Thanks in advance for any advice/solutions!

suncomb1

The alternator might be a high output unit and when you install one you need to run an 8 gauge wire from the output terminal of the alternator back to the battery + terminal thus by-passing the regulator. L. C. Engineering sells an adapter bracket to allow the installation of later model Toyota alternators onto older Toyota 4 cylinder motors.

INFINITY

i would check the voltage regulator if it is still in use. mine went bad and fried all of my bulbs once, 36 volts at the bulb sockets!

82yotacrawler

Voltage regulator is brand new. Its a Napa unit only couple days old now. May end up doing the later model alt swap.. starting to give up.

82yotacrawler

Ok so today I pulled off the new alternator that came with the truck and i noticed the plug looked slightly different then the half that goes into it. I took it to my local parts shop and they listed 2 different alts for an 82. Black plug and green plug. My harness has a black plug and the alt in the truck is green. The one with green is also slightly off center on one pin but my black plug fit it because its cracked. So i brought home the right alt and now i have No charge. With the engine running I have only 12.1v which is slightly less than i starte with before i starte it.

My question is: What could be causing the alt to not charge? My charge light also does not come on at all.

Any ideas?

ajoebob

you could of got a bad one out of the box. i make them test them before i leave the store becuse it has happened to me too meny times. i open the box and say i need this tested and they look at you funny then tell them agen you wount it tested.

82yotacrawler

i can see the charge light relay uner the dash, could this cause the alt to not charge? My charge light doesnt come on at all either and i checked the bulb.

suncomb1

Does your voltage increase when you increase the engine idle say to 2000 RPM? If it does then you are okay. At idle, 12 volts is normal and as long as you go to 13-15 volts at higher RPM your charging system is working. The charge light relay, voltage regulator and alternator system on 1982-1983 is different then what I was ever use to seeing. I have street rods and customs with GM alternators and they definitely work different at idle.

82yotacrawler

I get no voltage increase with rpms.. just stays at battery voltage.. i tapped on the charge light relay and it made my charge and brake light come on but i tapped it again and they shut off... either way stillno charge from alt.

i_love_tacos

i am having the same problem. new alt is not charging new battery. the engine does stay on longer without dying out. the truck would just die out with the old alt. hmmm........

82yotacrawler

Ok so i have figured the problem to be the voltage regulator even though my new one from napa doesnt work so instead of spending $40 on another one i got a gm alt and im going to fab up a bracket tomorrow to put it on the passenger side.

Thanks to everyone trying to help me out but im going to go ahead and admit defeat mainly because its a crappy set up so i dont feel to bad.

Cheers!

jtruck79

man i tell u after replacing my toy alt and reg about every 6 months from wheeling at about 180 bucks each round. i decided to go with ford ext. reg andd 70 amp alt. fabbed up mount on opposite side where air pump went. 18 dollar regulator and 35 dollar alt. way cheap. srry toyota

Kiroshu

theres an alternator for the diff transmissons. auto and man. If you have an auto alternator in a man it will charge too much. If you have a man trans alternator in a an automatic it will not charge enough and acctaully cause bookoo issues....

82yotacrawler

Got the chevy alt in on stock location for now.. its up against the water hose so im going to make a bracket to passenger side.. i have the excite wire jumped right to the charge wire and not seeing any issues. getting about 13.9 volts out of it. soo... brand new first gen toyota alt for sale! lol