74 Archer ignition switch question

These switches are made by Bendix and usually cost around $275 and up.
When you say it "locks up", do you mean that you insert the key in the
slot and the switch will not turn from the "off" posisition? Can you
remove the key easily from the off position when it does this?

Here are a few things to try. First, remove the switch from the panel,
mark down the connections and remove the connections from the switch.
Next, take out the 3 screws holding the thing together. Inspect the
springs and contacts to see if any of them are broken, bent, deformed,
burned, etc. If so, try to clean and/or repair them (180 grit sandpaper
followed by a good cleaning with contact cleaner). Reassemble and see if
it still locks up. If not, the contracts were the problem. I believe
Wag-Aero has an "overhaul kit" that consists of new contacts and
springs. Wag also has new units (push to start and the other kind).

If it still locks up and the contacts/springs looked good and clean, it
is probably the lock itself. A locksmith should be able to disassemble
it and put in new pins or repair it for a lot less than a new complete
unit will cost. These are pretty simple locks. If you have 10,000 hours
on the beast you might consider replacement though.

Good Luck,
Mike




My ignition switch occasionally locks up (with the key inserted) in the off
position when I try to start the engine.
.stuff snipped
The parts manual indicates 10-357210-1 for my serial number PA-28-180, but
that part has a push function in the start position (for priming?) that my
aircraft doesn't have. The other choice in the manual is 10-357200-1 that,
from the description, sounds like my switch.

Has anyone similarly found that their PA-28-180 uses the non-push ignition
switch instead of the push type called out in the manual? I'm guessing the
'push to prime' feature is for IO engines instead of O type that is stock on
Archers.