amp meter question

If an amp meter shows a discharge when you turn on the lights does that mean there is nothing wrong with the meter. I'm trying to get my A to charge - has a 6 volt starter and generator.I just got the generator back from the shop and I saw it being checked there - charges great in the shop. Doesn't show charge on my tractor so is it the meter or my wiring. Its a mag system so I only have a wire from the regulator to one side the amp meter and a wire from the other side to the starter. Starter post has neg battery cable (positive ground).I'm thinking a wiring problem.

Did you polarize the system and is the gen grounded to the tractor along with regulator and lite sw. You got more wires than you described or your lites would not work. You need to measure the volts on the batt terminal of the reg before engine is running then again when engine runs. Should read more volts when engine runs than when engine is off. Using the meter checking for ground put one lead on pos gnd terminal of batt. Then using other probe go from frame of gen then reg base and then to knob on lite sw got to have ground to batt on all componets for that system to charge.

THe field terminal on the gen must be hooked to ground through a F terminal on the regulator, or a wire to the light switch where charge is controlled by a resistor or full ground (not the light circuit) What do you have!? Jim

Mine is hooked from the generator to the F terminal. At the generator it is exactly as the shop had it when he tested it and showed me it works. All I did was bolt it back to the tractor and hooked the wire to the battery.

Do the following. With the tractor shut off, but all wiring connected, use a jumper to ground the field terminal on the generator for the next step. Next, use a piece of solid copper wire about a foot long (House wire 14 gauge with insulation stripped from each end for a half inch) to jump from the Bat terminal to the arm terminal on the regulator. This will spark a bit, hold it for one second. This polarizes the generators field poles. Remove the jumper from the field terminal to ground. Next start the reactor and run at 3/4th throttle, see if it charges. if so cool beans. If not, use that grounding wire to ground the field terminal again. This should cause it to put out maximum amps. If no joy, the generator may not be grounded to the tractor. Jim

First thing, I agree with the others POLARIZE THE GENERATOR before you do anything else as there's a good chance at the shop it got polarized for Negative ground !!!!!!!!

"If an amp meter shows a discharge when you turn on the lights does that mean there is nothing wrong with the meter."

It don't prove the meter is absolutely perfect and will indicate a positive charge HOWEVER it tells me its probably wired at the correct polarity.


"Doesn't show charge on my tractor so is it the meter or my wiring."


You can tell if its still charging regardless if the ammeter works or not. Put a volt meter on the battery tractor not running and if its charged it should read around 6.3 volts. Then start her up and at a fairly fast RPM if the charging system is working battery voltage should rise to at least 6.5 to near 7 or so volts subject to battery state and RPM and charging system. If it never raises voltage SHES NOT CHARGING

Finally to tell if non charging is a generator or a Voltage Regulator or cutout or control problem run through my Non Charging Troubleshooting Procedure linked below. It explains in Para 5 how to by pass the VR or manual Low High light switch LHDB charge control by dead grounding the gennys FLD post to see if its a gen or wiring or VR or control problem.

"I only have a wire from the regulator to one side the amp meter and a wire from the other side to the starter."

Typically the VR or Cutout Relays BAT terminal wires to the Load (NOT battery/starter) side of the ammeter while its other Supply side wires to battery often where the big cable attaches to the starter switch/solenoid input. That would allow her to charge if alls well.

BOTH the Genny and VR or Cutout Relay need good grounds, check for that !!!!!!!!!!!!!!!!

Run my Troubleshooting Procedure should answer your questions

http://www.ytmag.com/cgi-bin/viewit.cgi?bd=jd&th=458743

John T
John Ts Charging Troubleshooting