The proportioning valve meters the flow through the fan motor. The proportioning valve receives signals from the controller which gathers information from both the engine and hydraulic temperature sensors.
The hydraulic fan is used to cool the engine and hydraulic/hydrostatic systems. The hydraulic fan consist of a fan and hydraulic motor that is controlled by a proportioning valve.
NOTE: The proportioning valve is factory set and can not be adjusted accurately in the field. The adjustment screw is sealed with a tamper evident white material, if this screw has been adjusted the proportioning valve must be replaced.
If the flow from the proportioning valve is determined inaccurate it must be replaced with a new one from Bobcat Service Parts.
The fan speed is determined by the engine coolant temperature and the hydraulic fluid temperature. Depending on these temperatures the fan speed (RPMโs) can range from 0 to 4000 RPMโs.
The hydraulic fan speed at cold engine startup will range from 0 to 500 RPMโs until the engine coolant and the hydraulic fluid reach basic operating temperatures.
During normal operating temperatures the fan speed may range from approximately 1900 to 3500 RPMโs.
