Commander 4WD V6-3.7L VIN K (2007)
Water Pump: Description and Operation
Water Pump Bypass
Description
WATER PUMP BYPASS
The 4.7L engine uses an internal water/coolant bypass system. The design uses galleries in the timing chain cover to circulate coolant during engine
warm-up preventing the coolant from flowing through the radiator. The thermostat uses a stub shaft located at the rear of the thermostat to control flow
through the bypass gallery.
Operation
WATER PUMP BYPASS - 3.7L/4.7L
When the thermostat is in the closed position the bypass gallery is not obstructed allowing 100% flow. When the thermostat is in the open position the
pill partially covers the bypass hole, reducing the amount of bypass flow. This design allows the coolant to reach operating temperature quickly when
cold, while adding extra cooling during normal temperature operation.