H Generator - Works with F term grounded to battery?

Dan G · May 31, 2011

Ok, I"ve used John T"s diagnosis and it my H passed all the tests, but still wouldn"t generate DC. Replaced all wires (one at a time!)
took apart generator and put back together. Ammeter definately works, I went thru his whole checklist. Motor test on GEN worked too...went back over it and I missed step 6...
So I grounded the F terminal (to battery ground) on the GEN and jumped the BAT and GEN terms on the regulator and instant + volts on the ammeter. I shut it off, and restarted and as long as that grounded wire is on the F term it generates fine. What"s wrong? I"ve replaced almost everything on this tractor once already and I"d rather replace/repair the right faulty part.

BTW, GEN was professionally rebuilt 1.5 years ago, battery is 3 months old, and regulator is about 2 years old.

It"s a 6volt positive ground system without Cutout relay, (4 term regulator (BAT, GEN, F, L)

Can I just leave the F term grounded? Something is telling me no.

Denny ('60 Lo-Boy) · May 31, 2011

Grounding the F terminal proves the generator is OK but it is putting out current at it's maximum while it's grounded. Don't continue to run it that way. I would say the regulator is at fault since the generator is working. Get one at NAPA or similar and get the USA made not the offshore type. May cost twice as much but there is a reason for that.

Nebraska Cowman · May 31, 2011

yes, grounding the field is an old trick to make the generator charge.

Bob M · May 31, 2011

Dan - If the generator charges OK with the F terminal grounded it's time for a new regulator.

You DON'T want to run with the F terminal grounded! This causes the generator to "run wild" ie. with output regulation. This risks burning out the generator and/or frying the battery.

teddy52food · May 31, 2011

Try putting a good ground wire on the reg. base. It won't work if it isn't grounding.

John T · May 31, 2011

I guess FWIW I agree with Teddy AND Bob M. If she ONLY charges by dead grounding the gennys FLD post, the problem is EITHER the VR isnt well grounded OR its bad or the wires bad from FLD on Genny to FLD on VR.

You say 6 volt Pos ground with a cutout relay but then you mention a 4 terminal VR which is a bit confusing, but if its a 3 or 4 terminal full fledged VR and its wired correct it should still work regardless so long as the genny has been Polarized (HAVE YOU DONE THAT??? IF NOT DO SO) and the VR is suitable for your ground??

I agree to NOT just leave FLD premanently grounded as you risk overcharging.

John T

gene bender · May 31, 2011

You sure can there are tons of them running that way it is a quick fix for a bad reg. Depending on where your new generator is made the instructions will tell you if grounding the field makes it charge the reg is bad. I knopw of some thats been that way for 40 or so yrs and still running and charging.

Dan G · May 31, 2011

I did polarize and got the obligatory sparks. I did a few times to make sure. I ran a ground from the base of the VR to the battery ground to confirm it had a suitable ground. It had no effect. I put a meter between the REG ground and HOT of battery and got normal voltage. I'm thinking that I need to replace the VR? If so, where should I get it? They are dime a dozen and don't want another junky one.

John T · May 31, 2011

You might try Jim in New York at Agri Services www.wiringharnesses.com tell him John T says howdy

John T

FarmallJon · May 31, 2011

My '49 H with magneto ignition needs to have it's charging system diagnosed and fixed. John T., do you have a diagnostic procedure that Dan used? When I got my H, it had the four position headlight switch, and a genny with a voltage regulator. I'm told that if it has a four position switch, it did not use a voltage regulator? it just either charged on 'High" or "low" depending on the selected switch position? I'd rather have a voltage regulator, and not worry about the switch position.

John T · Jun 1, 2011

Jon, My standard generic troubleshooting procdedure is linked below, its NOT perfect or all inclusive but its a start. My friend Bob M has a good flow chart which also helps.

The older systems used a Cutout Relay (BAT and GEN/ARM Terminals) and the Gennys FLD wired to the LHBD light switch which could be set for Low or High charge. The newer used a full fledged 3 or 4 terminal Voltage Regulator where the Gennys FLD wired to the VR and NOT and low high charge switch for automatically regulating the rate of charge. (LHBD can still be used to turn lights to Bright or Dim) Its possible to convert from a cutout relay and LHBD system to a VR by wiring the VR correctly

BAT on VR to load (NOT battery/starter) side of ammeter, same as wire from BAT on cutout up to ammeter before.

GEN/ARM on VR to gennys ARM post

FLD on VR to gennys FLD post AND NOT TO LHBD SWITCH

and NOT use the gennys FLD wired to the switch but VR instead.

Hope this helps

http://www.ytmag.com/cgi-bin/viewit.cgi?bd=farmall&th=665110

John T
John Ts Troubleshooting

mkirsch · Jun 1, 2011

FarmallJon, your tractor could have been converted to a regulator at any time in the last 60 years.

Janicholson · Jun 1, 2011

I had to re-read it as well, it says without cutout.
Jim.

Dan G · Jun 1, 2011

quoted from post at 03:13:00 06/01/11) fixed. John T., do you have a diagnostic procedure that Dan used?

[b:d676657a30]http://ytforums.ytmag.com/viewtopic.php?t=328451[/b:d676657a30]

H Generator - Works with F term grounded to battery?

Dan G

Member

Denny ('60 Lo-Boy)

Member

Nebraska Cowman

Well-known Member

Bob M

Well-known Member

teddy52food

Well-known Member

John T

Well-known Member

gene bender

Well-known Member

Dan G

Member

John T

Well-known Member

FarmallJon

Member

John T

Well-known Member

mkirsch

Well-known Member

Janicholson

Well-known Member

Dan G

Member

Similar threads