Generator charging questions update II stumped

Followed John T's trouble shooting guide...thought that I had it narrowed down to the VR being bad.

Ordered a new one from Rusty...Forty seven fifty (and that included freight). Was here in 3 days.

Took me longer to get the new ammeter from the local (Frederick) CIH dealer.

Put the wire brush wheel in the drill, shined up where the VR mounts, shined up all of the connectors. Installed the new ammeter, new VR, made sure that the wiring matched the schematic in the owners manual, started it up and still no charge.

Go thru John T's steps again. Shows discharge when I turn on the key or the lights when not running. The only way that I can get it to charge is to short the field terminal to the case. With the cover off of the VR and the field shorted, at idle no charge but as I rev up the motor the ammeter jumps to the charge side and I can see the bottom contact in the VR pull closed. Can see the voltage rise at the battery with meter as I rev up motor also.

According to John's guide, it is pointing the area of the VR again, but it's new.

As I noted in the subject line, I'm stumped.

For those who didn't see the previous post: 340 Farmall, 6V Pos Gnd

Guys, Thanks in advance.

Edward

Once you have it charging, will it continue if you remove the ground wire?

Edward - A couple quick things to try:

1 - Run a temporary ground wire between the sheet metal regulator base and the grounded battery post. If the generator now charges whatever metal part the VR is mounted to is not grounded well enough.

2 - Check the wiring between the VR "F" and the generator "F" terminals for continuity. Could be there's an open circuit in the field wire inside the harness.

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Where did you purchase the VR? (I need a new one for my Super H and $47.50 is a good price...)

(quoted from post at 18:42:43 06/18/09)


[b:ae0a9adecb]Ordered a new one from Rusty...Forty seven fifty (and that included freight). Was here in 3 days. [/b:ae0a9adecb]

Edward

Click to expand...

looks like he got it from rusty

Bob:

I've put things away for the night (I'm on the east coast, should already be between the sheets!!). I did run a temp wire between the field post on the gen and the field term on the VR. No difference. VOM also said wire in harness is ok.

Will try suggestion 2 tomorrow.

Got the VR from tornholmsagservice dot com (Rusty Farmall)
Thanks, Edward

Teddy:

It stops charging when I remove the gnd on the field term.

Thanks Edward

(quoted from post at 22:23:19 06/18/09) Teddy:

It stops charging when I remove the gnd on the field term.

Thanks Edward

Click to expand...

he "bottom contacts" you speak of seeing pull closed when you rev the engine would be the cutout function, most likely.
The other set of contacts would be your field contacts (which should be closed at rest). Make sure those field contacts are actually making continuity.
You could even short them together with a screwdriver to see if that makes charge.

When the engine is off, and the battery is charged and connected (normal off state if it was fixed), the generator's field circuit is fully grounded through the regulator. This means that the windings that adjust the field circuit (by vibrating the field grounding points, sense that there is no voltage, and cause the points to remain closed. A test light is best for determining if this is in fact happening. I think it is not.

The test light must be a real bulb (even a headlight bulb from the tractor, an ohm meter or LED "bulb" will not load the system enough).

Remove the F terminal connection from the generator, at the generator. Attach one of the test light leads (if it has 2), or the grounding clip on the light if it has one lead and a pointed probe on the handle, to the negative (not grounded) battery terminal. Now every ground you touch will light up the test light bulb.

Touch the F terminal on the generator. I bet the test light comes on. This means the generator is grounded. Now touch the VR case. It may or may not light if not the VR is not grounded well dispite the preparations made.

If it does light, all is well with the VR ground.

Now touch the wire you removed from the Gen's F terminal. Notice how bright the light is (if it comes on at all) If the light is bright, check and compare the brightness to when you touch the point to the Field terminal at the (supposed other end of that wire) on the VR. If the brightness is different, or the bulb does not light, the wire going to the Gen's F terminal from the VR Field Terminal is bad. It may be that the existing wiring system (possibly from when it may have been wired as a light switch controlled (non-regulated)system is hiding a fault. If so, or if in doubt, use a new #12 wire to connect the VR Field terminal to the Gen's F terminal. Give that a try. Let us know the results of these tests, they load the circuits and can be more accurate than a Meter that will read incredibly small conductivity as though it were a solid wire. (some faults seem conductive when not loaded). JimN

Thanks Edward! I ordered my new VR from Rusty this morning...