This trick device is a normally open switch with 1/2" or 3/8" NPT male threads that screws into your manifold's water passage. When the coolant reaches 185°-215°, the contacts close, activating a relay which directs current to your electric fan. When the engine cools, the contacts open, and the fan stops automatically!
This arrangement is not adjustable, but is more rugged than other setups.
This sensor must be used with a fan relay! If installed as a gounding fan switch it will burn out!
We suggest our relay # 910-64032 w/wires & circuit breaker or # 910-64044 Econo Relay w/plug & instructions.
Make sure it is mounted in the manifold or radiator tank so that the bulb is submerged in the HOT engine coolant.