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Parts for old mag switch?

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asport22

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Yesterday when I did a run-up in the Jodel, it got really rough when left mag was selected. I tried it a few times, and found that if I put the switch in just the right spot, the engine smoothed out. Seems like a switch problem, although it's kind of a mystery to me how a switch can cause that problem.

The switch is an ancient, maybe WWII or even pre-war part, marked "A.C. Type (illegible)". No key, just a lever knob, and Off, Bat, L, R, Both positions.

I pulled it out today and took it apart. I suspect the source of the roughness is accumulated dirt, oxide, etc, that maybe was enough to kind of ground out both mags intermittently, with maybe vibration causing the intermittent part. That's unverified, though.

The bigger problem is that the switch contacts consist of cylindrical brass bits that are interconnected by shield braid that is attached to the bottom of the contacts by tubular brass rivets that go all the way through the brass bits. The rivet heads are actually the part that makes contact. The problem is that on the parts that comprise the left mag portion of the switch, the braid is failing, to the point that it's difficult to estimate remaining life. (I should have taken some pictures, but I'm guessing that if anybody has actual experience with these switches, they will know what I'm talking about.)

I assume my only option is to replace this thing, but I thought I would ask if anybody knows of a source of parts for this antique switch.

Second question: How many of you are flying with two toggle switches for mags? I've always kind of been nervous about not having a keyed switch if I ever end up at a fly-in, but is that a valid fear, or just paranoia?

Thanks!

Warren
 

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