VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1933-1936 Check out the heater blower switch on the '33

Single pole, double throw, note the open contact tabs on each side, the little tabs you can barely see drop down (up) to make contact with the terminals. Probably original to the car?

I note the switch does work via an ohm meter, but the blower motor does not blow. I am going to use the unused terminal for the aux elect fuel pump.

Doug

That worked out well.

I cleaned those black contacts with 000 steel wool,and they are nice brass color, now, and the blower motor works now that the contacts are clean,and the pump works when the switch is in the other position. And I didn't have to drill any holes or mount any other switches.

Doug

Switch just under the dash in the left side of the pic,and the heater.
Doug

Doug,
There is a good discription of the correct heater switch on Bill Barkers 1931 Chevrolet web site.
Go to accessories, click on heater. There are many pictures of the switch.
The switch was two speed with a wire wound resistor center off.
The original swich es are scarce.
The FS has a switch that can be used that is two speed.
Good luck finding one.
Randy

That is a simple 3 position on-off-on single pole double throw switch. Interesting that the patent was issued April 17, 1928. It was assigned to Cutler-Hammer.

The patent describes the operation as well as the design of the switch for ease of manufacturing. A key feature is the "quick" connect of the contacts. This prolongs the life of contacts in a direct current applications.

I doubt if this was original to the car.

My switch appears to be the exact same switch, but the resistor is missing. You can't see it in my pic, but the toggle is identical to the one below.
Doug

It would be interesting to see the original wiring for this switch with the resister. My guess is that there are only 2 wires to the switch. One is from the power source and connects to the center terminal. The other wire goes from one end terminal to the fan motor. The resister is wired between the terminals so it will send reduced voltage to the fan motor when that end terminal in energized. When the toggle is moved in the other direction full voltage goes to the fan motor.

That is how it would be wired, power to center, out put single wire from one (either) end of the resistor. The resistor is an add-on to the switch, not part of the switch. The wire to the motor would connect under one of the same screws that the resistor tab is attached under.

Doug