Voltage Regulator (ext.) / How it works (2 Viewers)

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Also interested in this. I have an '84 FJ40 and there is a high pitch noise coming from the VR. Can anything be done or is it on its way out?

Not sure I have the right answer for you, but I did just order a new VR and brushes. THey should be here this week so I will let you know if that fixes the issue or not.
 
Looks like mine is an aftermarket SS unit and I went out to start up and there was nothing...had battery tested and it wouldn't take a charge so replaced it. After installing it was hard to start and keep running (smoking etc) and wouldn't idle. Went to O'reilly and had tested and the VR is bad. It actually ran ok on the way home but still a little rough. My question after all that...would the VR cause those rough running/starting issues or could it be something else? If I run it the way it is until Tuesday when the replacement gets here, will it hurt anything? I typically only drive it a few miles at a time.
 
Interesting thread. I had an issue with my VR, and during adjustment, I stopped getting any charge at all.

I think it's just a coincidence, because it seems that no amount of bending will get it charge again. So it's probably the alternator.

Edit:

After working on it for another day, I realized that the gaps were out of spec, and fixing that fixed my issue. If you look back at OPs picture here, you can see that the Angle gap and the Point gap will act as a starting point for adjustment (if it's out of spec like mine was). When you depress the spring so that it's touching the top of the coil, the Angle gap should be 0.2, but the Point gap has both an upper and lower limit.

You first make sure the High Speed Point PL2 is in the correct position by bending it so that the Angle gap is at least 0.2mm, and then you bend the Low Speed
Holder PL1, towards or away from PL2 until the Point Gap is 0.25-0.45. Working from there, I was able to get it functional again and subsequently adjust the voltage by bending the Adjusting Arm.
VRpic.PNG


It's still not perfect, but it's pretty damn close. The only thing I seem to have an issue with now is that there is a bit of a swing in current. Sometimes the Ammeter jumps up and down a bit. I suspect it may take a bit more fine tuning to get it right, but I also suspect that it may be a result of wear on the part, so I'm not sure how perfect I can really make it.
 
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OK.. I have read this thread multiple times over the last three days and have learned a lot.. Thank you Rudi and others...
However,,, my problem..
Purchased a 77 FJ55 last year, got her running, driving, even drove out to the pig rally in Arkansas this past year but did a quick turnaround. (Florida).
I wanted to sort out and clean up a couple of wires in the engine compartment, replace a couple of short length non OEM wire installations with OEM wiring I have from other projects. Fun stuff. Truck running great. All lights, switches, blinkers, working. Loom looks unaltered. No worries..
I start by reading all the above info. I have a 77 FJ55 wiring diagram. And I cannot find the voltage regulator.. I know right.. Grins.. but seriously, I was thinking it is in the engine compartment somewhere... USA model. I have followed the loom from start to finish both sides. And under the dash.. Cannot find the darn thing. Cant find a plug that has the wiring for a six plug, four plug, or three wires unattached, or an indication of where it was installed...my loom appears to be virgin unwrapped, except......where the loom comes close to the ignitor. My ignitor and coil have several additional wires on them... my alternator has the three prong, NON IVR, with the white/green wire and the white/black for the ground...coming out of the loom and correctly attached to the Alt... My gauges work, including the charge needle.
My thinking is the VR was originally located in the engine compartment, passenger side, on the firewall close to the coil/ignitor...there are two nuts on the firewall that are vacant/empty, and I'm hoping/thinking. If that is where it is supposed to be, Im thinking a previous owner removed it, and hooked the wiring up to the coil and ignitor, but cut in non OEM wiring.. I dont see the white/green... I don't see the white/black... My next step is to trim back some tape on these non OEM wires to expose what they are attached to. But if the VR is under the dash, I'll focus more there....

So, big help would be hopefully, if someone knows where the VR should be on a 77 pig...
Any assistance much appreciated...
 
OK.. I have read this thread multiple times over the last three days and have learned a lot.. Thank you Rudi and others...
However,,, my problem..
Purchased a 77 FJ55 last year, got her running, driving, even drove out to the pig rally in Arkansas this past year but did a quick turnaround. (Florida).
I wanted to sort out and clean up a couple of wires in the engine compartment, replace a couple of short length non OEM wire installations with OEM wiring I have from other projects. Fun stuff. Truck running great. All lights, switches, blinkers, working. Loom looks unaltered. No worries..
I start by reading all the above info. I have a 77 FJ55 wiring diagram. And I cannot find the voltage regulator.. I know right.. Grins.. but seriously, I was thinking it is in the engine compartment somewhere... USA model. I have followed the loom from start to finish both sides. And under the dash.. Cannot find the darn thing. Cant find a plug that has the wiring for a six plug, four plug, or three wires unattached, or an indication of where it was installed...my loom appears to be virgin unwrapped, except......where the loom comes close to the ignitor. My ignitor and coil have several additional wires on them... my alternator has the three prong, NON IVR, with the white/green wire and the white/black for the ground...coming out of the loom and correctly attached to the Alt... My gauges work, including the charge needle.
My thinking is the VR was originally located in the engine compartment, passenger side, on the firewall close to the coil/ignitor...there are two nuts on the firewall that are vacant/empty, and I'm hoping/thinking. If that is where it is supposed to be, Im thinking a previous owner removed it, and hooked the wiring up to the coil and ignitor, but cut in non OEM wiring.. I dont see the white/green... I don't see the white/black... My next step is to trim back some tape on these non OEM wires to expose what they are attached to. But if the VR is under the dash, I'll focus more there....

So, big help would be hopefully, if someone knows where the VR should be on a 77 pig...
Any assistance much appreciated...


i bet you have a updatd 2 wire green plug fj60 unit on there now

right ?
 
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Well, that would make it easy, but nope.. I have the older (pre IVR) 3 prong. I have an 82, and had an 83 40 both with the IVR's atop the Alt's, so art least I can check that off the list.
My voltage regulator is either a lot smarter than I am ( a possibility) or PO removed it (seems like after reading attached threads a few have done that), or it's been relocated to parts unknown...
 
My voltage regulator is either a lot smarter than I am ( a possibility) or PO removed it (seems like after reading attached threads a few have done that), or it's been relocated to parts unknown...

Without a VR, wouldn't you just cook your battery? I've definitely seen voltages upwards of 16-18VDC with a messed up VR.

A good sanity check would be to measure the voltage at you battery terminals at 2000 RPM. Might not be a smoking gun, because you could still have a bad VR, but if it's really high, that would at least point to a missing VR. If it's normal (14.4VDC or thereabouts), then you've either got voltage regulation or a bad alternator that isn't putting out enough juice to ruin your day.
 
Without a VR, wouldn't you just cook your battery? I've definitely seen voltages upwards of 16-18VDC with a messed up VR.

A good sanity check would be to measure the voltage at you battery terminals at 2000 RPM. Might not be a smoking gun, because you could still have a bad VR, but if it's really high, that would at least point to a missing VR. If it's normal (14.4VDC or thereabouts), then you've either got voltage regulation or a bad alternator that isn't putting out enough juice to ruin your day.
Honestly I don't know much of anything when it comes to electronics.. Yes, I'm that guy.. However, me being able to locate the VR compares to some people rebuilding an engine.. and will be a great starting point. Which is partly why I love Toyota wiring and the color codes and schematics. Im thinking the VR is right where it should be, but I've been at a loss up to this point. I'll know later today. The whole thing about measuring voltage is still a pay grade above where I'm currently at, but that is where I'm heading and why I love doing this as a hobby. Great mud is here, and thanks to all.. Common sense tells me I have one, plus the loom is otherwise original as previously stated..
 
The whole thing about measuring voltage

This is the same operation as measuring the voltage of any battery. Put the multimeter in DC voltage mode in the correct range (should be the 20 VDC range on pretty much all multimeters), put the multimeter leads in the right holes (black goes to common, red goes to the hole with a "V" next to it), and hook it up to your battery terminals.
If you hooked it up backwards, you will just get a negative voltage reading, no problems.

I use this multimeter for automotive stuff because it also has RPM and Dwell on it for setting other stuff, but I'm not endorsing anything. It's just what they had one day when I was at an Autozone, and it still works fine 20 years later.


I can't link to amazon from this forum (won't let you) so this is the name of what I use: Actron CP7677 AutoTroubleShooter

All you have to do is hook it up and position the thing so you can see from the driver's seat. Then you put your foot on the gas and watch the meter. If it goes past 15VDC, that's too high. If it's super high, like 16 volts or higher, you are cooking your battery.
 
There was a suggestion about making a plug with a resistor between the field and the ignition. The value of 10 ohm is for a 12v system. Should it be 20 ohm for a 24v?
Since the rotor have 20 ohm (ext 24v). It would give a current of .6 amp. Any suggestion for a resistor which can handle that.

I did an "emergency harness" which once it is connected in place of the rectangle VR plug. It allow to connect the round (Can) VR, a resistor for the trickle charge or an internal VR alternator (using B for S,IGN and L). Not tested yet...

BTW I realise that the Canadien round green plug is backward in the FSM. The tab should point up like the rectangular general market. At least for me (trace wire on a OEM unit)
Thanks
 
There are 2 different models of 6 wire VR's. One that is not using the N and one that does use the N terminal to function.
In case yours doesn't work..... connect the N (Null) terminal on the VR to +12V

Rudi
Ciao Rudi & all,
I've just finished a major restoration of my 1979 Bj40 (24v), and I was following this GREAT thread to understand what's going on with my charging circuit that does not work.

I've installed also a voltmeter... that showed everyday I was going lower until actual sad 23.6.

I have a new AVR512 with 6 connectors, and 50A ammeter that works (I've studied it a long time ago and understood why it was not working and fixed it).
In dash there was no charging light but during restoration I've realized that it was just missing a 3 inches piece of cable from harness to dashboard, there was even the plug just behind it.

So, this morning, as VR was not working I've tried to to connect N to +24V (B) as suggested here, seemed a good advice.

YEAH !
when I've plugged N to B I've heard a tic from it (uuuhhh good) and then I've start engine, and AM went steady to +40A.
Super happy.

BUT when I shut down engine... nothing happened.
EDIC was not working anymore.
Shut down by pressing brake and then realized that engine fuse blowed.
No worry.. new fuse, turn the key.
Blowed instantly.
I've tried to disconnect VR plug... just a test.
Blowed again.

During restoration I've done a lot of work to go back to factory connections, getting rid of years of mess.
For example when I brought in 1990 she had a VR from a FIAT tractor installed, with charge lamp ecc, not good to see but it worked so I let it where it was.
Until restoration, when I tried to went back to factory, my harness right now is, as far as I know the same as diagram.

This afternoon I will take apart EDIC relay to check if it works testing E+IG and then OIL to see if stops, finally ST to see start position.
Hope I've not burnt anything into it :(((

Can't really figure out what went wrong, do you have any hint about this?

Thanks for your kind suggestions.

Emanuele
 
Update:
EDIC relay is fine.
Then I've fused the connection between IG and N ( if I connect B the lamp is always on).

This is the situation:
If I take apart the engine fuse, then charging circuit is fine, 25.6V, +30 amp (the batteries needed a good recharge)... don't know if at sometime amp go back to zero, I've left it running for 10 minutes.

If I put the engine fuse, while charging, it blows.

If I take apart the VR fuse, so that IG + N are not connected anymore it won't charge the batteries (light is on, amp to minus something), engine fuse is ok and EDIC relay works

Pretty...isn't it?

Again, if I'm missing something or you have suggestions on what to do or try... super appreciated.

Grazie
E
 
Not sure if anyone chimes in on this thread anymore but thought Id ask a question. this thing is 12 pages so I read a bunch but not all so hopefully this wasnt covered.

So got this 82 hj47 troopy from a guy in OZ and everything works great but I noticed that the battery wasn't fully charging, so I read up on adjusting the VR and thought I got it right. but after a while it seemed to be working poorly like it originally was. tried adjust ing again but then the adjustments made no difference? Id be driving on the highway with the windshield wipers going and the battery moniter I got will say 11.3 - 11.7 and when its in the 11.3 zone the wipers appear to struggle. so I figured the VR was bad and bought a new one. but it in seemed to be charging more without opening it up and adjusting. but its still doesent do 14.2 at 2000rpm. I tried adjusting the new one and like the old one it didnt seem to change. Is my alternator going? another thing. theres two coils in my VR with the "adjustable tab" one facing up and one facing down. to adjsut do you only tough the upper facing one or do you do both? I only touched the upward facing one. any insight would be awesome.

thanks!
 

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