On my '65 Skyhawk, I was having lots of problems with regulator/alt. The
Cessna designed switch is terrible. Contact resistance is too high and
if you look at the switch inside you can see wear and contamination. A
good military DPST toggle would be a good choice.

Larryskydives wrote:

Michael,

I had a problem on a 56 172 where the regulator went out after three months.
We found that on the master, there were a set of contacts for the field
circuit that were bad. Replaced the master switch and no more problems. May
or my not apply to you plane.

--
Regards, Ross
C-172F 180HP