Generator 12v Car Running = Idiot light on ? Help!

[watkinscapital]

First I know there are alot of forum topics about this but I have read through most of them and gone back to the car and tried.

The idiot light stays on when engine is running and will not go off, until car is turned off. I have checked and doubled checked all wiring and I am fairly cofident its done right. The battery is brand new and only getting 12 when car is running and when its rev'd it drops to 11-12.

Any Suggestions would be greatly apprciated? I am not sure what else to do.

What I have done:

I did polarize Gen.

Battery is brand new.

I Just put in a new voltage regulator.

Tested gen is putting out 40 amps at when rev'd ( http://www.nls.net/mp/volks/htm/gen.htm ).


Cleaned tabs and put in new connectors for idiot light.



new Regulator.


Generator:

[Dale M.]

Do you know if new regulator is good?

Here is basics for testing.....

Generator/Regulator Test!

Disconnect all wires from Generator. (tag them so you get them back right)

Connect a test light ( 6 or 12 volt what ever is appropriate) on generator to the "D+" terminal ... Ground other side of light.

Ground "DF" or "Field" on generator.

Start engine... If light comes on and brightness increases as engine rpm comes up your REGULATOR is bad ( generator works ) Caution over revving engine to fast will cause light to burn out.

IF light stays dark ( does not light ) , check test setup again to be sure its right... If you rev engine up and light still does not light GENERATOR is bad.

People with experience using a VOLT-OHM meter could use the meter instead of light... look for VOLTAGE increase..

Dale
_________________
Lives his life vicariously through his own self...
1970 "Kellison Sand Piper Roadster" For Street & Show.

All suggestions and advice are purely my own opinion. You are free to ignore them if you wish ...

[watkinscapital]

With a voltmeter I Put Pos. on ( D+ ) / neg on ground and grounded (DF) to frame with jumper wire.

Results were a reading of 12v then when rev'd it went up to 35-40?

I figured this meant it was good, so I replaced the voltage regulator. Started car up and the idiot light was still on when started and would not go off even when rev'd.

I have not tried a test light but will get to that this morning after coffee.

[Russ Wolfe]

Disconnect the #61 wire at the voltage regulator. The light should go out.
If it does not, then that wire is shorted someplace.
_________________
Society is like stew. If you don't keep it stirred up, you end up with a lot of scum on the top!--Edward Abbey

Gary: OK. Ima poop.

[watkinscapital]

It does go out. When unplugged, and did the same with both old and new regulator.

[Russ Wolfe]

If you are getting 30-40 volts when full fielding the generator, Then the generator is good, and putting out properly.
Are the wires good from the generator to the regulator? Especially the DF wire?
That is the wire that controls the generator, via the regulator.
Do the same test you did at the generator, only this time do it at the regulator.
Disconnect the DF and the D+ wires at the regulator, and ground the DF wire while measuring the voltage at D+ wire.
Could be you have a break in the DF wire.
_________________
Society is like stew. If you don't keep it stirred up, you end up with a lot of scum on the top!--Edward Abbey

Gary: OK. Ima poop.

[Dale M.]

Did you happen to reverse DF and D+ wire when you replaced regulator?

Also regulator appears to be mounded on fiberglass.... Is it GROUNDED?

Dale
_________________
Lives his life vicariously through his own self...
1970 "Kellison Sand Piper Roadster" For Street & Show.

All suggestions and advice are purely my own opinion. You are free to ignore them if you wish ...

[watkinscapital]

I will really inspect wires, and test the regulator. Yes wires were in correct spots, however at one point they were reversed (not sure if this could have damaged the generator itself). The regulator is grounded although maybe not grounded good enough (have cable going from right side of regulator box to frame).

I will do some more testing soon and if nothing changes (I suspect its something obvious that Im missing), I'll order an alternator kit.

[lostinbaja]

[watkinscapital]

lostinbaja:

Did you add anything beneficial here or just trying to get your post count up?

I am trying to figure out what is going on with the system which was my reasoning for the post, it could be a bad ground, it could be a fried wire. If you’ve got some suggestions for me to try out I may get some garage time tonight so let me know.

[zozo]

I'm following this thread VERY closely, as I'm have the exact same problem with mine. I've also installed a new VR, have a new battery, etc, etc.

The one thing that I'm thinking might be the problem with mine was the DF post was loose in the generator. The lock nut had backed off for some reason. Initially, this was accompanied by the DF wire to the VR being broken at the connector and losing contact.

I had thought that tightening the DF post and putting a new connector on the wire would turn the trick, but I find myself in exactly the same situation as you.

[watkinscapital]

I've been swamped lately and have not had time to get out in the garage. Its funny you mention the DF post being loose because mine was as well, but i figured it was ok because I was getting a amp reading off the Gen.

[Russ Wolfe]

You may have a broken wire to the DF post, inside the generator.
It is a solid wire inside there, and if it wiggles around too much, it will break.
_________________
Society is like stew. If you don't keep it stirred up, you end up with a lot of scum on the top!--Edward Abbey

Gary: OK. Ima poop.

[zozo]

[zozo]

To whomever posted this picture in whatever thread I found it, THANK YOU, THANK YOU, THANK YOU. After looking at this picture, I was able to diagnose my problem, and resolve it. A little time, a little solder, and voila, the problem has been fixed. I'm charging properly, and the idiot light has been extinguished.

Once again, THANK YOU to whomever posted this picture and provided the associated narrative on how to fix it.

[Markymark875]

Is that behind the pulley, I am having the same problem as you guys to, I wonder if I might have broken that wire while putting a screw driver in that slot to tighten the pulley nut?

[zozo]

Yessir, just pull the pulley off, look in there with a flashlight, and all will be made clear.

I fixed mine in about 20 minutes, and I only have one eye. If I can do it, anyone can.

Good luck.

Feel free to PM me if you have any questions about the process.

[Markymark875]

Thx for the help, the wire on mine is not broken, I cleaned the brushes/and copper?? cant remeber name of it, light is still on now, but very dim, seems to be charging a little

[dunebuggy09]

I'm having same issue change yep gens and three vr. My car Will run with battery cable off while car is running. Idot light on. D+ and df have power on them when car running.

[Dale M.]