calling john t!!!! charging problems on h.

john , i got the h re-wired for 12v neg ground, put the new regulator in it, and the new rebuilt genny. wired according to the schematic that has been posted on this site. genny wont charge. when i polarized the genny, got a real good spark at the bat and gen terminals. sooo, following your guidelines, i grounded the field on genny, no charge. (ammeter does swing discharge with light on engine off) also voltmeter showed only 12.2-12.5 volts.doesnt change with the field grounded. i left the field grounded on the genny and jumped the bat terminal to gen terminal, got a big discharge swing on the ammeter and a good spark at the wires. i then did the motor test on the genny. with the field grounded, applied bat voltage to the arm post, genny motored slow, when i pulled the ground off it speed up momentarily but then coasts to a stop. i am kinda thinking the rebuilt genny has a problem. your thoughts?????

I (though not THE John T) agree. The generator is not operating predictably. Make sure it gets load tested at the shop you had it rebuilt. JimN

thanks for the reply jim, these dang charging systems will make you pull your hair out. spent the morning trying to get the h together, then it wouldnt charge. had lunch, got the farmall cub out to mow. now that critter aint charging. looks like a bad regulator on that one. typical day on the farm.....

One more last time effort.
With it shut off, jump the F terminal on the gen to ground. While grounded, run a jumper cable to the gen from the bat non ground side. Touch the Arm (big) post with the cable end. A fair 20 amp spark should happen. Then start it up with the field grounded, and see what happens. A bad regulator ground can be the problem, Jim

Glenster, The Jimster knows this stuff as well or better then me, and it looks like we agree. Heres my thoughts:

When she was running and you jumped the VR's BAT to GEN/ARM and you got a heavy discharge n spark, Ima thinkin thats cuz the battery was reverse discharging through a BAD maybe something shorted genny. If the genny was working and you made that jump (BAT to ARM/GEN), thats supposed to simulate a cutout relay closure so the genny can charge the battery (if its good that is).

Also with the gennys FLD post dead grounded to tractor frame and the cutout relay by passed (BAT jumped to ARM) the VR is essentially out of the equation and if theres no charge its cause of a bad genny.

Another thing pointing to a bad genny is its failure of the Motor Test. When you apply voltage to the ARM post it should spin fairly fast n smooth n steady, but then speed up some but continue running if the FLD is ungrounded. If it dont it about has to be a bad genny in my opinion.

Of course BOTH the genny and VR need good grounds to work properly but from what you say that genny just isnt acting right and still wont charge even if the VR is out of the equation (assuming grounds and other wiring is correct)

John T

I had sounds like the exact same problem with my gen. I took it to a guy that works on them and he polished the armature and it charged fine after that, but also I had a bad VR in the mix.