[Farmall] Generator/regulator wiring

Dean Vinson dean at vinsonfarm.net
Tue Sep 5 10:22:35 PDT 2006


My newly-acquired M doesn't charge, so over the weekend I took the hood off
to look at the generator and regulator.  (Regulator is mounted on top of the
generator).  Two immediately obvious problems:  (a) the wiring was rotten
and (b) nothing was hooked up to the generator.  Both wires that come from
the ammeter/switch box were connected directly to the regulator, and nothing
at all was connected to either the A or F terminals on the generator.

The regulator looks brand new.  One side has three terminals marked "F",
"BAT", and "L".  The other side has no terminals sticking out, but down
underneath it, accessible from the underside in the space between the
generator and the regulator, is one unmarked terminal.  Right next to that
terminal is printed "1409 6V POS", but I assume that's just the model number
of the regulator and not a label for that otherwise-unmarked terminal.

The tractor is 6V, positive ground, electric start.

I've got new wiring in place now, but am not sure of all the connections.

-  I ran one wire from the ammeter to the "BAT" terminal on the regulator.
The original wire from the ammeter had been connected to the "L" terminal on
the regulator, but I assume that was a mistake on the part of the previous
owner.  The parts book diagram makes it very clear that it's supposed to be
connected to the "BAT" terminal.

-  For a hand-start tractor, the parts book shows a wire running from the
switch in the ammeter/switch box to the F terminal on the generator.  For an
electric-start tractor, the parts book shows that wire being folded back and
not used, and then a separate short jumper wire from the generator F
terminal to the regulator F terminal.  I assume I should go ahead and match
the diagram (jumper between F terminals, nothing from the switch), except
the original wiring was connected to the switch and had been connected to
the regulator F terminal.  The regulator connection could easily have been a
mistake, but the connection to the switch had been there for a very long
time and was presumably factory-installed.  Should I do the jumper between F
terminals, or connect the switch to the generator F terminal?

- Both diagrams in the parts book show a jumper from the generator "A"
terminal to the "GEN" terminal on the regulator.  The regulator on my
tractor doesn't have anything marked "GEN," but I assume that's what the
unmarked terminal on the front side is for.  If I hook it up that way, can I
screw something up in the regulator if it turns out to be wrong?  What is
the "L" terminal for?

Thanks--

Dean Vinson
Dayton, Ohio
www.vinsonfarm.net






More information about the AT mailing list