Shut off switch

I have a 1940 JD H hand start. Of course it has a magneto and I know I can short the magneto to the frame to shut the tractor off. I want to find a switch and a place to mount it on the tractor that doesn?t stick out like a sore thumb, so to speak. Any ideas?

Standby. I got to get new low res pix of what I use and then I can post them. Only way to do it as it is positive engine shut off. Be back...

Can you tell us which magneto you have?

Both a WICO C and a WICO X were available with an external kill post.

The ?kill? post can have a spring loaded button that will stop the engine.

Here are a few pix. The H was done about 30 years ago and was a low budget quickie job. The B is the standard setup I use most of the time. The feature of using the switch is once it is in kill mag position, the tractor will NOT restart with out making the change to on. The push tab on side of mag will not do that, plus it is hard to reach, especially in emergency shut down situation. I will try to make a stand alone post on the subject as it can be viewed as a safety issue. OK, lets see if pix works. HTH, George

try again

39 JD H

H

40 B

37 B
Looks like got pix this time

Cheap toggle switches can get dust and moisture in them and make for a weaker spark out of the mag.

Shielding it like in the photo looks like a good idea to me, wouldn't hurt to put a weatherproof switch boot on the handle, either.

Another idea would be to use a mag "kill" switch for an old IH tractor. They are designed for the job and reasonable weather-proof. NOT sure if there's any good new ones to be had, or if "The Land of Almost Right" has ruined/cheapened them as much as some other electrical and fuel system parts.

"Thud! Kerplop! GASP! Crash!"

"What the heck was THAT?"

Just a few members of the "Correct Police" stroking out, apparently! ;-)

<img src = "http://oi67.tinypic.com/2cdbn6p.jpg">

On these old JD tractor it is best to shut them down by shutting off the gas. Let it die then open up the drain on the carb and drain out what is left. Learned the hard way years ago what can happen if you do not leave the carb drain open when not running and it cost me $500 In a rebuilt carb because my old one had broken due to condensation and ice in the carb

Thanks George, the pictures helped!

The magneto has an external post and I like the idea of a kill switch mounted there as it will look clean. Any idea where I can buy a switch like that? Thank you.

I've tried to shut it down that way, but its a real SOB to get started after. Thank you for the advice.

Depending on the carburetor and its stop adjustments and if it has the proper little vertical springy stop etc etc, some (Not all) tractors could be shut down by holding back firmly on the throttle and you did not use any mag kill switch method.

On Wico X Model series of mags many had that external stud/post where you could attach a wire n dash switch which killed the spark if it got shorted to ground. The dash mounted Push/Pull kill type switches were a favorite of mine as they looked nice almost original and work fine.

THAT BEING SAID when I farmed with those tractors and was a used tractor dealer my preferred method (to make easier re starts) of shut down was to turn the gas off let the tractor idle and finally die due to no gas remaining. AFTER it died I then opened the throttle to wide open so it was left in that condition for the shut down period.

If you're having difficulty re starting that's either an ignition or mag or timing or carb issue, but regardless I had easier re starts if I turned the gas off versus killing the spark PLUS if the float didn't close off properly you didn't flood the carb n engine !!!!!!!!

John T

Thank you for the input John T.!

We had a G that had been heavily farmerized. It had a "momentary" switch low on the battery box out of the way. It looked like the starter switch from an early '50's ford truck wired to the mag stud. We always shut off the gas and let it run dry at the end of the day, but used the kill switch if we needed to shut if off for refueling etc.

Being hard to start after shutting off the gas is that when hot or cold?? If at both then the float maybe sticking so you tap on the carb. If only when hot well that is the nature of a hand start tractor