New guy here, J3 owner.
Having some puzzling issues with a new-to-me A7 mag switch and new P-leads for the Slick mags (fairly new; maybe 125 hrs). The new P-leads ( from here:
https://bogertaviation.com/products/p-leads-slick-style) come with the P-lead shielded wire and a ground wire for each mag. The P-lead terminals were connected to the P-lead connectors (with wafer insulation washers) on each mag and then to the appropriate posts, L and R, on the A7 mag switch. The ground wire terminals were connected to the GND screws on each mag and then both other ends were connected to the ground post on the mag switch.
Everything worked great for several days and flights and then the engine would not turn off when the mag switch was turned to the “off” position.
Disconnected the wires at the mag switch, cleaned the posts with Scotchbrite, checked continuity, reconnected the wires and all worked fine for another few days. Then, it refused
to turn off.
Disconnected the P-leads and ground wires at each end (mag switch and at the mags), checked continuity of the wires and the mag switch again, all Ok. Reconnected, and all worked fine for a few more flights. Then, it again wouldn’t turn off.
Remived the A7 mag switch and cleaned/serviced it according to this:
https://www.shortwingpipers.org/forum/attachment.php?attachmentid=8258&d=1428156785
Then checked continuity, reassembled, and again it worked fine for a couple of test starts but then wouldn’t turn off at the end of the first flight.
Any ideas?? I’m at a complete loss and totally mystified. I spoke with a guy at Champion Aerospace before installing anything and he suggested (if I recall correctly) leaving one ground wire disconnected. The local A&P didn’t do that and connected them to the mag. Not sure if that’s a contributor or not. Regardless, I’m open to any insight at all.
This Cub came to me with some ugly toggle switches as mag switches. Wanting to restore it to “original” as much as possible I found and had the A7 installed. Almost ready to go back to the toggle switches as I’d prefer to go back to the toggle switches. This really should t be this difficult, should it?!