TM 5-2420-230-24-2
Fan Clutch, Electric (008-026)
B3.9 and B5.9 Series Engines
Page 8-32
Section 8 - Cooling System - Group 08
Fan Clutch, Electric (008-026)
General Information
WARNING
The cooling fan will engage when the engine is started.
To avoid personal injury, do not put your hands in the
path of a rotating fan.
The Cummins-developed electromagnetic fan clutch prod-
uct is an integrated package with the clutch, bracket, shaft,
bearings, pulley, and fan spacer designed as a unit. An
engine coolant sensor and/or a refrigerant pressure sensor
(if equipped with air conditioning) will engage and disen-
gage the clutch. The fan clutch engages when the coolant
temperature sensor or the refrigerant switch is closed. it
disengages when either of these sensors return to the open
position. The most common temperature switch is set to
close at 91C [195F]. Contact the OEM for recommended
temperature switches. The temperature must be set above
the opening point of the thermostat. When cooling is
needed, a powerful electromagnet engages the fan. The
fan is either fully engaged or fully disengaged. The OEM
could have a manual override switch to engage the clutch
manually at the operator's command. The electromagnetic
fan clutch is driven by a poly-vee drive belt and is available
with an accessory drive for vee-drive belts.
Clutch wires must be oriented at 2 o'clock instead of 12
o'clock. The following table lists the component parts of the
electric fan clutch.
L-1088
