Super H switch

I have a 53 Farmall Super H that is wired with separate power wires to the ignition switch and to the light switch. Never been a problem wired this way but recently had another operator leave the lights on during the day and none of us noticed it. This is the 2nd time I've had this happen resulting in a dead battery.

Tractor has original lights in addition to a trailer wiring harness. My 24' hay ride trailer has 3 running lights on each side and 2 tail lights on each side in the back. Total of 10 bulbs. Not LED's

Tractor is 12v with an alternator.

Ignition switch is original and correct for this tractor.

Light switch is after market but I finally broke down an bought a new 12v OEM switch to be installed soon.

I want to rewire so all power goes through the ignition switch.

The questions are:

Will the ignition switch handle the amperage required to run the lights?

Will the new OEM light switch handle the amperage of all those bulbs?

Dean - Answers to your questions:

1 - Probably not. The OEM ignition switch is designed to carry only coil current only, about 3 - 4 amps. Figure headlights + trailer lights are gonna draw at least 15 amps. The ignition switch will carry it a while but will likely get hot. You do not want that(!)

2 - Yes. The OEM style light switch is designed to carry (3) 6 volt work lamps; about 12 - 15 amps. (3) 12 volt lamps will draw half of that. Add a few amps for the trailer lights and you are still good.

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A couple solutions to your "lights left on" problem:

- Install a battery disconnect switch. Open the switch whenever you are finished using the tractor. Cheap and easy to install. It's also a good safety feature if you have little people who may climb on the tractor, and it eliminates the possibility of an electrical fire when the tractor is parked.

- Add a 12 volt relay to the light circuit. Supply the relay coil from the switched side of the ignition switch. Then wire the light switch supply thru the normally open relay contacts. Modular 12 volt auto relays are cheap and compact - you can probably squeeze one inside the ammeter box. The downside of this option is you won't have lights unless the ignition switch is "on" and the engine is running. (Ignition on and the engine stopped can burn out the ignition points).

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BTW nice looking SH! (I have a somewhat shabbier looking twin to yours....)

I like your solutions. another might be a tiny hole next to the ignition switch push pull with a red LED glued to it from the back. this would be on when the lights were on and remind the operator to shut them off. Jim

Thanks Gentlemen! I appreciate the help.

Good idea Jim!I may use it on some of my tractors.Steve