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1980 LUV, 1.8L ISUZU. When the truck is on and idling, the GEN light is always on, no matter how clean or tight I make the battery connectors, and any other connections. Voltage is around 13.25 volts while running. Engine does not die or hesitate when battery is disconnected, so the alternator is giving a charge...

I noticed today while working on it (just replaced carb float and valve) while it was running I started to hear a clicking noise coming from the driver side of the engine bay. Located it to be the black box mounted on the fender well on the driver side. This is the voltage regulator, yes?

I also noticed that while the regulator was clicking the gen light in the dash was flashing. Has the regulator gone out or is the alternator beginning to fail? Or could it be needing a electrical re-ground? I did find a couple loose grounds but after messing around with them there was no difference.

Also, the only time the regulator is clicking is when the engine is running.

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1980 Chevy Luv (1.8L I4, 4-speed) - Should never have bought this pile of crap
1987 Nissan 300ZX (3.0L V6, 5-speed) - Best car I've ever owned

That is your voltage regulator, the clicking is the regulator turning on and off so you don't over charge, I am guessing the regulator is bad but I would first do the fuse box clean up first. The fuse box is a common issue to our trucks, it causes all kinds of strange stuff.

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Certified pilots, looking down on people since 1903.

The wiring for this truck is a nightmare. Someone went through and rewired a lot of stuff for the voltage regulator and alternator. I cleaned fuse box some more (it's pretty bad, might need to replace) and no change. Uncovered wiring for the alternator and regulator stuff, it has all been hacked and still has some spots of dry cracked wiring.

Truck will start fine, run fine. 13.5 volts at the battery. 14.1 volts at all fuses (?)... If I disconnect the battery while the truck is running it stays running, at first. I'll also hear the bearing inside the alternator start to whine faintly. Re connect battery and alternator stops whining.

After a few minutes (I'm guessing once voltage starts to get high?) the regulator will start clicking on and off slowly. Now I'll have usually 13.1 volts at the battery. When it was doing this I disconnected the battery again and the clicking stopped, and alternator was still charging, I reconnect battery and regulator will starting clicking, (with voltage bouncing from 12.8 to 13.1) and progressed to a rapid clicking with gen (and sometimes heat) light flashing in dash.

Shut the truck off and let it sit for a moment. Restarted truck and it ran fine, alternator still charging and regulator clicking slowly, again 12.8 to 13.1 volts. Pulled the regulator fuse and nothing happened. Pulled all the fuses to be sure and regulator was still clicking on and off and voltage was still 12.8 to 13.1. Shut truck off, put the fuses back in.

Now it gets weird, started the truck back up and the regulator clicked maybe three times and the truck will start to run like crap and voltage drops to 12.3 and regulator stops clicking, and GEN light is constantly on in dash. Disconnect battery and truck dies. Restart truck and same scenario. Alternator no longer charges. If I let it sit for a while and come back it starts over at the beginning.

:/ Could it be that the alternator is just taking a crap and making the voltage regulator go crazy? I'm not very familiar with the external type voltage regulators. Why is the regulator and alternator still working if I pull the regulator fuse? Could it be the hacked wiring is my issue ?

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1980 Chevy Luv (1.8L I4, 4-speed) - Should never have bought this pile of crap
1987 Nissan 300ZX (3.0L V6, 5-speed) - Best car I've ever owned

I'll give it a try here. Hacked wiring sometimes means all bets are off regarding normal operation.
Two things here lead me to believe your idle speed is too low. #1- the gen light should be off if your idle speed is 900+.
#2- Running crappy means the engine is probably below its normal 900 rpm and thus the light would be on.
Regarding the clicking regulator: Yes the clicking noise is the regulator doing it's job, however it is not operating properly if you can see/hear this. Usually means the regulator has a open resister located under the body of the regulator. So--yes regulator replacement time.
As far as the alternator whining noise, it usually means an increased load on the alternator. Maybe not regulating properly with the battery disconnected temporarily.
Why it still charges with the fuse out? Don't know, possible hacked wiring?

Hmm it idles kind of high in my opinion. I would say it's probably around 900 RPMs. (Truck doesn't have a tach) It idles smoothly until the charging system starts to act up and the battery stops receiving it's charge.

I'm thinking about getting a wiring diagram, some mil-spec wire and other necessities and soldering up a new harness. The wiring through out the truck looks rather ragged and old, and a lot of hack spots.

Also the truck didn't do this (that I noticed) until recently. When I had first bought it voltage regulator was unplugged, I plugged it back in and haven't noticed anything until recently, but I have noticed the GEN light goes on and off as it pleases, and the FASTEN SEAT BELTS and HEAT lights will turn on if I rev the engine, the heat light will flicker off and FASTEN SEAT BELTS will stay on for a few moments, been doing this since I bought it.

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1980 Chevy Luv (1.8L I4, 4-speed) - Should never have bought this pile of crap
1987 Nissan 300ZX (3.0L V6, 5-speed) - Best car I've ever owned

With all the strange things going on I would start with checking and cleaning all grounds.

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Certified pilots, looking down on people since 1903.

A very good idea.
If the alternator quits charging, the voltage regulator quits powering the fuel pump relay and shuts down the fuel pump. So--yes that would effect the engine running.

Voltage regulator stops clicking and alternator stops charging, thus the truck is now running off purely the battery and starts to die because low voltage and old battery haha.

D'oh! it may help to mention that the starting/ignition wiring was pretty bad on the hacking too and I have already gone through and temporarily re wired it separate from the rest of the system so I could get it home when I bought it, left all original wiring how it was, just disconnected and ran some of my own wires. There was no change in any issues except for the mystery of random no spark. I ran new wiring for ignition, fuel pump and starter. (to get it home.)

Another reason why I just want to solder up a new harness or find a new one, this harness is probably part of my issue, but I'm going to see what I can find to see if I can get stuff to work out right before I throw new parts at it.

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1980 Chevy Luv (1.8L I4, 4-speed) - Should never have bought this pile of crap
1987 Nissan 300ZX (3.0L V6, 5-speed) - Best car I've ever owned

Do the Fuse Box fix. A search will find the procedure. Buss bars need to be disassembled, cleaned and re riveted or soldered.
Don't waste any more time on the issues you describe until you fix the fuse box.

I will be replacing the fuse box with a set of 6 slot ATC type fuse blocks. Going to consist of 2 common hot feed 6 slot blocks, one block for voltage regulator, fuel pump and ignition, the other for lighting and other misc. electrical circuits.

Today the truck didn't act up at all. At first GEN light was off and alternator wasn't charging, then tapped the gas, heard the regulator click, GEN light came on and was getting 13.9-14.1 volts at battery after that, alternator charging and still nothing happening when fuses are removed. I do believe the problem does lie in either the fuse box or the hacked up wiring. Let it idle for almost 30 minutes and voltage regulator did not start clicking repeatedly and alternator was giving a good strong charge.



Areas circled in red are what bother me. Crimped and twisted together wiring with tape (you should've seen how much tape I took off!) Definitely a issue for me, harness is probably full of electrical resistance and corrosion, along with the fuse box needing replacement. The worst of the hacking is in the wiring that goes to the bottom of the fuse box.

Also...



...where does this wire go? I'm pretty sure its a ground, just want to know if it needs a specific spot. When I stick the positive needle from the multimeter to one of the fuses in the fuse box and touch negative needle from multimeter to this wire I get 12 volts. Solid black wire goes through the harness to the voltage regulator.



According to the Series9&10 wiring diagram this should be wire E for the alternator? But I don't know where it would go there doesn't look to be a spot for this wire on the alternator? If it is just a ground I could connect it to one of the mounting bolts for the alternator?

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1980 Chevy Luv (1.8L I4, 4-speed) - Should never have bought this pile of crap
1987 Nissan 300ZX (3.0L V6, 5-speed) - Best car I've ever owned

I got sick of burning out voltage regulators and put an 80 amp 1 wire alternator in. I can take some photos and let you know how its wired if you like.

Matt

Truck still not showing any voltage regulator issues today.

Pulled apart wiring, made some patches and started hooking everything up the way its supposed to be, and removed all the temporary wiring for ignition and starting and fuel, and hooked them all up to their proper pig tails in the stock harness.

Came to notice the fuel pump relay is not working. No power to fuel pump unless I jumped power to it (BR wire) from the relay connector. Also noticed that, according to Series9&10 wiring diagrams wire B on the voltage regulator (WR) runs from the voltage regulator directly to the fuel pump relay.

How important is the fuel pump relay and resistor bypass relay to the voltage regulator? With the temporary wiring I had set up it completely bypassed both of those relays on the passenger side of the engine bay.

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1980 Chevy Luv (1.8L I4, 4-speed) - Should never have bought this pile of crap
1987 Nissan 300ZX (3.0L V6, 5-speed) - Best car I've ever owned

Replaced fuel pump relay with a Nissan 5-point relay out of the Z parts car. Works beautifully. Drove truck around the block a few times. No issues.

Everything on drivers side of the engine bay for wiring has been looked over and patched and covered in the generic black plastic coverings. Everything for starting and ignition and fuel now work flawlessly.

Removed the hacked up wiring for the alternator/voltage regulator and re-wired it with new wiring. Used the heat shrink type crimp connectors. I hate using crimp connectors honestly, but better than twisting and taping wires. Also, soldering iron seems to have grown legs and disappeared



I figured I would have fun with it while I was going through the harness. All ignition wiring is labeled with blue, lighting is labeled with yellow (as was stock wiring?), and voltage regulator/alternator labeled with white, taped to hold it together underneath the coverings, and to aide in wiring identification if I ever have to go back through.



Removed the voltage regulator wires from the stock fuse box and ran them to a new 6 slot ATC fuse common hot feed panel. When running GEN light is no longer on constantly, and FASTEN SEAT BELTS light turns on with the key and turns off about 30 seconds after. Then turns on for another 30 seconds after engine starts, then shuts off again. (Normal?)

...and still no voltage regulator issues. Battery is charging normally with 13.9-14.1 volts.

One thing I've still noticed is that the HEAT light will light up and flicker for a moment before turning off when the truck is first started. Is this normal ??



And (above) is what remains, the mess of wires there by the fuse box will be sorted out and fixed up (thats the other area of hacked up wiring, still working on fixing it.) Perhaps the flickering HEAT light will disappear once I finish up with the harness?

Also, the black coverings you see are what I am using to cover the entire harness. All the wiring on the opposite side of the engine bay has been repaired and covered. (Will get pic in daylight tomorrow.) All that remains is the hacking that was done by the fuse box, and installation of second 6-slot ATC fuse panel for remaining electrical items.

_________________
1980 Chevy Luv (1.8L I4, 4-speed) - Should never have bought this pile of crap
1987 Nissan 300ZX (3.0L V6, 5-speed) - Best car I've ever owned

Good job on the rewiring, looks quite professional. Not surprised that fuel pump circuit from Z car works for the Luv, as the Nissan 240 Z had the very same fuel pump as the Luv. If you ever need to order a stock Luv fuel pump and they say no listing, just order one for a Nissan 240 Z which they probably do have, same pump.
That whole pump, relay, regulator circuit was mandated for safety only. In an accident the motor should stop, alternator will then stop, fuel pump will stop, and not continue to pump gasoline on a maybe burning vehicle. All vehicles now do this and that was the way Luv decided to do it.