Farmall H charging system

About 2 weeks ago I posted about my farmall having a charging problem and it has a new battery. I polarized my generator and my ammeter went to the charging side. This lasted for a few starts.
I took one person's advice and put on a new voltage regulator, polarized it and it took about 2 minutes before the ammeter went to the charging side. Turned on my lights and at first the needle went to discharge then went to charge. Again, this lasted a few starts. Tonight the H fired right up for me and i left it run for about 25 minutes at 3/4 throttle. Needle was reading charging for about 5 minutes and dropped to zero. Lights made the needle discharge. I shut the tractor down and came back about 15 minutes later and it would not start. It was trying to turn over but just wouldnt do it. The genny was rebuilt last year but maybe it isn't working anymore. I put my digital multimeter on the battery and it is giving me a reading of 13 volts while running, with lights it was dropping about a volt ( I am unfamiler with multimeters so I guess i'm doin it right). any help is GREATLY appreciated! Thanks in advance.

If a good battery ran down in only 15 minutes after you shut her down, I wonder if the Cutout Relay contacts inside the VR stuck closed??? If so right after you shut her down the ammeter would have swung to a heavy - discharge and the genny would get warm. In fact if the belt had been removed it would have spun like the DC Motor it actualy is.

That 13 volt running sounds "decent" as setting the battery voltage would be 12.6 but at fast RPM with a good genny Id expect it to rise to 13.5 or up near 14 depending on the battery state and VR and genny and RPM.

FIRST make sure the Cutout Relay inside the VR isnt stuck closed cuz if so the battery will discharge rapidly and the genny get hot.

Next Id check for a good case ground on the VR and genny itself, maybe try a ground jumper wire (also insure a good tight belt???)

Next Id run Para 5 of my Troubleshooting Procedure where you ground the gennys FLD post to see if she charges then ?? If so but NOT otherwise the VR isnt well grounded or its bad. if she charges fine when you ground the gennys FLD post and the VR has a good ground I SUSPCET THE VR

Check for that stuck cutout relay !!!!!!
Check the belt tension !!!!!!!!!
Check for a good VR ground !!!!!!!
Run my Par 5 grounded FLD test !!!
If none of the above, maybe a VR problem

Take two aspirins n call me at the office

John T
John Ts Troubleshooting

John, thanks for the reply and the troubleshooting link. You say to ground the genny fld post to see if it charges then. When I do this do I leave the wire that is already on the fld post on there and run my ground wire or do I remove the fld post wire and then attach my ground wire?

If all is well (VR works and has a good ground) it should be doing the job of supplying a ground to the gennys FLD post. When I do it I dont unhook anything I simply use a jumper from the FLD pst on genny to case/frame/ground to see if she charges then. If so but NOT otherwise you know the genny itself is okay so the problems EITHER the VR isnt grounded or its not working correct or the wires bad from FLD on genny to FLD on VR.

John T

Thanks John, I'm anxious to try this out, hopefully I'll have time tonight. Just out of couriosity, would starting the tractor with a 12v booster pack effect anything? I've had to use my booster pack several times over the last year to start it.I've always removed it as soon as the tractor fired.

Chris - Jumping your 6 volt H with a 12 volt jump pack - while not recommended - should not cause problems (I've had to do it it a few times...)

However you MUST disconnect the jump pack the instant the engine fires! Otherwise if it spins the generator up fast enough to close the VR cutout relay, it CAN damage the VR. (I learned this the hard way!)

If you use the booster pack, or any 12v battery, a simple way to avoid charging system damage is to jump to the ground on one lead (close to the starter, or a starter bolt) and (with it in neutral, brakes set, ignition on) touch the other jump lead to the terminal on the starter motor (polarity does not matter because it is not putting 12v into anything but the starter motor.
This will assure no regulator damage. Jim