83Toyota88

iTrader: (1)

I have one more thing to try before I replace my alternator. Everything I have read on GM alts says it gets grounded through its mounts on the engine block. But the bracket I made is painted so it cant be getting a ground. No ground will keep the voltage regulator from running and could also affect the charge circuit maybe. Worth a shot I think.

sarajevo--

Well, while that might sound reasonable, I have to note that the site I bought the bracket from recommends you paint the bracket before install. I myself have not, but I do not see that as being the problem unless you painted the bolt holes as well. But even then.............

83Toyota88

iTrader: (1)

Well that didnt work lol. Got it removed and Im going to O'Reiley in the morning to seap it out. Dont know if I trust Autozone's alts.

83Toyota88

iTrader: (1)

Got a new alt from Autozone this morning and installed it and drove up to test it because it didnt seem like it was working. It tested for voltage regulator failure. Super pissed.

sarajevo--

What? A new one with a faulty internal regulator?

Also, this morning i started my rig and the external fan was rubbing the altenator housing in the top left corner (looking at front of truck). I think the stock belt is too small. I have heard of some people using a belt that is 1.5 inches longer, but I am not sure how to get a belt like that other than by measuring mine and then measuring a host of them at the auto-store. Is the belt my problem? Do I need to shim the fan out some? or the pully from my yota alt?

83Toyota88

iTrader: (1)

I have heard some people having to shim their pulley to make the belts that the yotas use fit better. Im using an aftermarket pulley from summit racing . A lot of people do use a longer belt as well. When I sized mine I tried several at Autozone to get the right fit.

I just got another new alt and I was looking at a piece of technical documentation that it came with on all the terminals and what they are and according to it the L (charge circuit) wire must have voltage on it with the key turned to ignition so tell the alt to start charging. Now when the key is turned to the ignition position but no engine on I get voltage on the sense and ignition wires but none on the charge wire. This has to be my problem.

83Toyota88

iTrader: (1)

So on your wire harness on the cs 120 what wires did you tie to where? Wanna compare it to mine.

sarajevo--

My mechanic told me to bend the fan blades in a little to deal with the orientation of the alt shaft and the pulley. I will try this.

I did not hook up the LAMP wire from the alt because I didn't know where to run it. But the black small wire went to the red toyota wire, and the large red wire went to the white toyota wire. Everything works except for my charge light which keeps coming on (its not hooked up, need to bypass it some how). I need to find a 12v switched power source for it (cig lighter?)

83Toyota88

iTrader: (1)

I actually found a switched 12V under the hood earlier. On the passenger fender there is a relay for emissions something and it square and gray just like the charge light relay under the glovebox in my truck at least. The relay had two of those fusable links attached it it and one of the wires in it was a switched 12V. Ok so I everything I read about these cs alts says you have to have voltage on that charge light wire to the alt to male kt start charging. But you say you didnt hook up it ul and your works?? This is so confusing lol.

83Toyota88

iTrader: (1)

Think I got my alt charging now. See my notes below:

Found these notes on a pirate thread:



http://www.pirate4x4.com/tech/billavista/Wiring/Part2/

Found a big note in that installation bulletin I mentioned that says L activates the alternator and It will not charge without voltage present at L.

So I removed the red ignition wire from the F terminal and moved it to the L terminal. S is still hooked to battery along with battery charge wire from alt. I think it worked. Battery was 12.5V with engine off. Turned it on and went to 13.10V and so far it has slowly climbed to 13.57V I watched the tenths place on the multimeter climb by +1 maybe every 30 seconds to a minute. Also this paper that came in the box with the alt it said to give the alt about 15 mins to fully adjust the voltage regualtor.

However when I turned the headlights on the voltage starting dropping but the battery also doesn't have a lot of charge since I kept running the engine with the alt not working before testing everything.

83pingpong

That's a great description on the Pirate 4x4 site. Thanks Memphis 83Toyota88!

I put a new battery in my truck finally, abuot a month ago. The old one just would not hold a charge. But while I was installing the horns a couple of weeks ago, I got about 16-17 volts at the horn connector while the engine was running. I think the voltage regulator needs to be replaced. Can you replace JUST the internal voltage regulator if that's all that's failed??

Maybe the over-voltage shortened the life of the old battery.

83Toyota88

iTrader: (1)

See below for internally regulated alternator:
http://autos.yahoo.com/maintain/repa...ques033_2.html

Yea pretty much with these GM 3-wire alts if it has a "I" terminal that's what excites the alternator and if it has the "F" you have to use the "L" terminal to excite the alternator. Does your charge circuit/light function properly?

83pingpong

The alternator light shuts off after start-seems to work. Exciting voltage circuit might be fine.

I have NOT inspected to see if I have an external regulator yet, but parts lookup shows a separate regulator, for about $50, with a really SHORT connector harness that makes me think it mounts on the alternator housing... This truck has been all OEM so far ('83 SR5 lngbed 4x4), so I doubt it has been converted to an internally regulated alternator.

I will check to be sure, but it looks like I need a new voltage regulator.

83Toyota88

iTrader: (1)

Oh I thought you had a GM alt conversion thats why I asked about the charge light. If its still stock then you have an external voltage regulator on the driver side of the engine bay next to the ignition coil. I just ripped mine out. See pic below:


Black box is external voltage regulator.

83pingpong

I'll take a look tonight. Thanks for the photo. Yup-looks exactly like the photos on the parts websites.

I replaced the entire ignition system already, and quite familiar with that driver's side wheel well. It is probably not far from the GM ignitor I mounted, attempted to use, and then disconnected, abandoned, and went back to stock components (Oh, by the way, it turned out to be the fuel pump on that one )

I'll check voltage while running one more time, but I think I'll be throwing another $50 for the regulator.

83Toyota88

iTrader: (1)

Funny thing is the same part for a 79 pickup is only $27. Wonder why ours cost so much more lol?

83pingpong

12 volt? Wasn't the '79 a 6V system OEM? I know they switched to 12V at some point. When did they change it?

Not that it should make such a big difference!

83Toyota88

iTrader: (1)

I just went back and looked at it and our truck year only has one voltage regulator rated for a 55 amp alternator but under the alternator section there is a 40 amp alt as well as a 55 amp. On the 79 you can voltage regulator for a 40 amp alt or a 55 amp alt. The 40 amp regulator is $27 and the 55 amp regulator is $44. Weird.

83pingpong

I'm getting 15 volts with the headlights on! They're bright!
And, the alternator light (and hand brake warning light) stayed on until I drove for a few minutes and went out when I revved past 2500rpm! I think the my voltage regulator is dying.

It's all stock, so should be a simple replacement issue.

edit: GOT ONE...Duralast VR756- 12 month warantee. I saw that I could get a Denso "OES" replacment for as little as $34, but not locally. This should protect the battery and the rest of lights and components for another year anyways.

83Toyota88

iTrader: (1)

Did you ever solve the problem with the fan on the alt rubbing on the housing? Mine is doing it a little too.