Wisconsin TJD

Greg K · Oct 3, 2014

I have an OLD Vermeer trencher with a Wisconsin TJD. Engine. The fuel pump quit so I put an electric one on it. The issue is that it has magneto ignition, which requires a wire to ground out and the electric pump needs switched hot.
Since I have the worlds worst memory and Murphy lives in my back pocket

I want to automate the fuel pump with the ignition somehow. I cannot find a keyed switch that switches 2 poles at a time or that has 3 poles and switches between the two to a common screw. Can I use a vacuum switch from an auto application, and would one be rated heavy enough to handle a small electric pump? Any other ideas? I have it on a toggle switch now but I can picture the boys playing and leaving it on or me just leaving it on.

Paul from MI · Oct 3, 2014

Just wire a small relay with the coil in parallel to your fuel pump. hook one side of the NC contacts to your magneto, the other side to ground. When power is applied the contacts open, allowing the magneto to spark.

Bob · Oct 3, 2014

Since you state you want to have a keyed switch, there are all sorts of garden tractor/small engine ignition switches available that have a "magneto kill" feature when "off" and an "ACC" or power terminal that is "hot" when the switch is "ON" that could be used to power a fuel pump when "ON" on, and "kill" mag ignition when "OFF".

Greg K · Oct 3, 2014

Boy do i feel stupid. The minute I read your answer I realized I had one of those laying around. Sheesh! Thanks for pulling on my head until the loud popping noise indicated my head left my rear.

thanks guys.

Bob · Oct 3, 2014

Don't feel bad, sometimes the OBVIOUS is NOT "obvious"!

I have an IH A with a mag, and I installed a keyed switch of that type so I can leave it at old iron shows knowing no one can muck with it and start it and run over folks with it if I have pulled the key.

(It has a little Hitachi alternator, which is "excited" by the terminal that will feed your fuelpump.)

Paul Janke · Oct 4, 2014

When I put an alternator on an old magneto ignition tractor, I use an oil pressure switch to excite the alternator. That might not work in this case because the fuel pump wouldn't work until there is oil pressure. I realize the solution given already is probably the best, but I mentioned this because in the case of my tractors, I just shut off the gas to shut it down and any manual switch could be forgotten

Wisconsin TJD

Greg K

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Paul from MI

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Bob

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Greg K

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Bob

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Paul Janke

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