Choke Temperature Control Switch: Description and Operation

Fig. 16:

The single stage control switch, Fig. 16. operates as follows:
The single stage control switch shortens choke duration only above 80° F Below 55° F, electric heat is not available until the engine is at normal operating temperature. Normal engine heat will then warm the control and energize the choke heater, but only after the choke has opened by engine heat.

The dual stage control switch operates as follows:
The dual stage control switch shortens choke duration above 80° F and stabilizes choke duration during cold weather operation. During hot weather operation, electric assist heat is hotter than during cold weather operation assist level.

Cold weather heat levels are regulated by an electrical resistor connected to both terminals of the control. Below 55° F, electrical power is reduced by the resistor. Above 80° F, the resistor is bypassed by a switch inside the control to supply full power.

Engines started during cold weather conditions will experience two levels of choke heat, low during engine warm-up and high after engine warm-up. High heat levels occur after the choke is open to insure an open choke condition under all driving conditions and minimize choking action which can occur after short stops during cold weather operation.

Engines started in hot weather conditions will not experience low choke heat levels. Engines started hot will only experience high heat because the switch is normally warmer than 80° F

NOTE: The heating element should not be exposed to or immersed in any fluid for any purpose. An electric short in the wiring to the heater or within the heater will be a short in the ignition system.