ENGINE AR-BASIC 0R8551 - Caterpillar

4N9072 SWITCH (Jon W. Hobbs Number 22258)(1) Terminal connected to insulated contact. The other contact is connected to the body of the switch. Switch contacts are normally closed.(2) With paddle in vertical position, the force (F) on rivet head (2) necessary to open contacts of switch ... 1.2 .1 oz.(34 3 grams)(3) Length of paddle ... 2.58 in.(65.5 mm) When the switch is installed in engine cooling system, the flow of coolant at cranking speed of the engine does not have enough force to activate the switch. When the engine is running at low idle the flow of coolant has enough force to activate the switch.