Topic: Alternator / Charging problems 83 22r

[Turtle Bite]

My buddy has an 83 with the 22r and we are having problems diagnosing why the truck is not charging, heres what we have done:

Cleaned and checked battery cables
Checked charge wire for good connection
Grounds look good
old alternator tested, was bad so:
Bought new alternator from shucks, installed, no change
replaced voltage regulator with another (not new but fairly sure it is good)

The battery is fairly new but was low on water, so we topped it off. Couldnt hear it boiling as far as I could tell.

The charge light is on and the voltage is pretty steady at 12-11 with the lights ect. on. Is it possible that we fried the new alternator with a bad voltage regulator then when we put the second regulator on it didnt make a difference?

Yes I know we could do the chevy alt swap but he would rather use the toyot alt.

How do I test the voltage regulator? I only have a 1980 FSM. Any other ideas?

[kneedownnate]

DO NOT BUY AN ALTERNATOR FROM SCHUCKS!!!  They are junk out of the box.  Call your toyota dealer and ask for a rebuilt factory toyota alternator, way better.  I had a kragen alt toast my wires, then the next 3 I got as replacements all had problems, with the last one having a bad bearing out of the box.  Yes you could have ruined the new alternator with a bad regulator, you generally wanna replace the two as a pair.  If the battery was low on water you could have ruined it as well, could have plates touching.  This is one area that you don't want to be stingy on, too easy to have it fail in the wrong spot.

[brainlessfool]

what he said.

[Duffil]

Did you disconnect the battery when you hooked the alt up?

[8D3TOY]

went through the same thing a few months back, just because the charge/brake light is on does not always indicate a charging problem.  I replaced everything involved with the battery & charging system on my 83 then I finally gave in and took it to an independent Toyota mechanic, his explanation was that the charge light and brake light are primative check engine lights, idiot lights, my motor was running really rich and the computer triggered these two lights to indicate a problem, he rebuilt the carb and replaced a vacume switch and they went off! Maybe I got ripped off but it made sense to me.

[Bob Garrett]

A bad charge light relay can cause the light to stay on even though the alt is charging. Use a digital voltmeter and measure the voltage across the battery while the engine is running at a fast idle with all accessories off. You should read around 13-14v.

[Turtle Bite [OP]]

Update: We took the new ALT and got it checked, failed "lamp on voltage", same as original alt. We exchanged that alt for one we tested before install and installed a new regulator. Charge light is still on and alt is not charging, voltmeter reads 12volts at fast idle...


The battery was low on water, were are going to put in a known good battery and replace the charge light relay. We did dissconnect the battery cables to install all the parts.
Thanks for the help guys.

[Bob Garrett]

Don't replace the charge light relay until you test it first. There is a test procedure in the Factory Service Manual. If you don't have one, let me know and I'll send you the steps to test it when I get home later today. BTW, the charge light relay merely controls the charge light. it has no effect on the actual charging.

Have you tried running a temporary jumper for the charge wire? When I had this problem with my 83, I jumpered the charge wire and it started working fine. Turned out the wire was badly corroded inside the connector that attaches to the alt.

[Turtle Bite [OP]]

Update again: Replaced the charge light relay and put in a known good battery. Ran another charge wire to the battery. Still no change, 12 volts. Right now I'm am all out of ideas short of putting a Chevy alt on there.

Someone on another board scanned the FSM for me so I know the test procedure for the relay but I couldn't remember how to check for continuity with my ohm meter and i had an extra so i just swapped them.

[79coyotefrg]

Update again: Replaced the charge light relay and put in a known good battery. Ran another charge wire to the battery. Still no change, 12 volts. Right now I'm am all out of ideas short of putting a Chevy alt on there.

Someone on another board scanned the FSM for me so I know the test procedure for the relay but I couldn't remember how to check for continuity with my ohm meter and i had an extra so i just swapped them.

12volts with everything on  or everything off??  engine at what rpm??

at 1200 rpm with nothing on i run 15+ volts,

if shucks is anything like autozone,  you might get 5 alternators befor you get one that works 

[79coyotefrg]

Update again: Replaced the charge light relay and put in a known good battery. Ran another charge wire to the battery. Still no change, 12 volts. Right now I'm am all out of ideas short of putting a Chevy alt on there.

Someone on another board scanned the FSM for me so I know the test procedure for the relay but I couldn't remember how to check for continuity with my ohm meter and i had an extra so i just swapped them.

12volts with everything on  or everything off??  engine at what rpm??

at 1200 rpm with nothing on i run 15+ volts,

if shucks is anything like autozone,  you might get 5 alternators befor you get one that works 

[Turtle Bite [OP]]

It put out 12 volts regardless of rpm with all accessories off and the voltage dropped according as headlights, etc were turned on. Battery voltage was at 12.5-12.7 when measured out of the truck.

Well the final update is the three prong harness was supplying no voltage at any of the terminals. Since I didn't have a FSM to figure out exactly what that meant and start stripping the harness to figure out what was going on, I got a 12Si GM alt off of my demolition derby car that had been recently rebuilt and now it charges like a champ. Basically I gave up on the the toy charging system. All that was needed to install the gm was trim the large mounting hole on the gm alt and extend the the top adjustment bracket on the block. We also ended up using a 36 inch long belt instead of the 34.8 inch that was on there. The wiring could use some looming and zip tying but it works and got him charging.
When we returned the the toy alternator it  failed every test the machine gave it, and WAS NOT BAD when we installed, we had it tested right out of the box. And it was installed with a new regulator from the start.

[Turtle Bite [OP]]

Oh and thanks for everyones help, Especially Bob Garret.

[kneedownnate]

. When we returned the the toy alternator it  failed every test the machine gave it, and WAS NOT BAD when we installed, we had it tested right out of the box. And it was installed with a new regulator from the start.

This is exactly what I went through too.  I bet if you pulled the sub harness that goes from the alt up to the main harness and peel all the tape off you'll find a problem in there somewhere.  My problem was I bought my truck from a house electrician, he had done a couple of splices in that harness and when I tested with an ohm meter a couple of the wires were very inconsistent.  I redid the splices and it all checked out good, no problems since.

[Resist]

Like Kneedownate said. Check your harness. I had the same problem and found the hot wire from the alt was the problem. Replaced it and never looked back.