Wiring Questions

Fri Aug 03, 2012 5:58 pm

I am in the process of re-wiring my '49 Cub from scratch. I have magneto ignition and 6V cut out with a 4-position light switch. Does the rear work light come on at the same switch setting for the headlights? It seems as if the rear light should be switched independently. My switch setting indicators are L, H, D, & B. What switch position should be used when the engine is not running?

Another issue: When I got to the point of wiring the single pole grounding switch, I checked the terminal on the magneto with a continuity tester - one probe on the terminal and the other on a head bolt. (This is without the kill switch being wired up yet.) I get a completed circuit indication. Is this as it should be? It doesn't seem quite right to me, as grounding the magneto is the method of killing the spark.

Re: Wiring Questions

Fri Aug 03, 2012 6:32 pm

thiggy wrote:When I got to the point of wiring the single pole grounding switch, I checked the terminal on the magneto with a continuity tester - one probe on the terminal and the other on a head bolt. (This is without the kill switch being wired up yet.) I get a completed circuit indication. Is this as it should be?
Yes. Depending on manufacturers design, typically the kill wire terminal on the side of the magneto is grounded inside the magnet in two areas.
1) Through the points, when closed to ground.
2) Through the primary winding to ground.

Re: Wiring Questions

Fri Aug 03, 2012 6:54 pm

If your battery and charging system is in good working order, use the L position while your are using the tractor in the day time, use the H position when using while the headlights are on, The D is for dim and the B is for bright. while not running L or H will be OK , all this is in the owners manual

Re: Wiring Questions

Sat Aug 04, 2012 8:37 am

Not sure about magneto Cubs, but a 6v wiring harness is about $50. I am pretty partial to a quality wiring harness where the colors match the diagram and the connections are soldered with shrink wrap. The A&I harnesses on ebay are pretty nice and comparable to the 'factory' ones.

Good (not great) diagrams are in the Operator's Manual.

Re: Wiring Questions

Sat Aug 04, 2012 10:41 am

According to my wiring diagram, the taillight has its own terminal on the switch. It comes on at the same brilliance whether the headlights are bright or dim.

The H or L positions are fine when the tractor isn't running, as the lights will be off. I use the H position if I'm not running the tractor for long, so it charges the battery faster. If I were running the tractor for more than, say, 10 minutes, I'd put it on L to avoid overcharging the battery. (The H and L refer to the charge rates for the generator.)

Re: Wiring Questions

Sun Aug 05, 2012 12:29 am

well said by all.