ARMY TM 9-6115-604-12
NAVY NAVFAC P-&633-12
462. MAINTENANCE OF IDLER PULLEY ASSEMBLY. The fan Idler arm and pulley assembly consists of the fan Idler
arm and pivot arm subassemblies. The fan Idler arm and pulley assembly is spring loaded to maintain proper tension on
the fan belt.
a. Replace.
(1)
Remove the shrouds and grill assemblies from the radiator assembly in accordance with paragraph 4-61
(2)
Remove engine fan (54, Figure 4-45) and ribbed V belt (51) in accordance with paragraph 4-61.
(3)
Close the valve on water filter head and remove the DCA water filter elements to gain access to the mounting
bolts holding the pivot arm support (49) to the engine block flange.
(4)
Unbolt the pivot arm support (49) and remove the fan idler and pulley assembly (22) from the engine block
b. Repair. Repair the fan idler arm and pulley assembly (22, Figure 4-45) by replacement of damaged or defective
parts.
(1)
If necessary, remove entire fan idler and pulley assembly (22) following step a, above. Otherwise the pivot
arm subassembly (36) may be separated from the fan idler subassembly (23) by removing hexagon head
capscrews (19), lockwashers (20), and ring dowels (21).
(2)
Disassemble fan idler arm and pulley assembly (22) as follows:
(a)
Remove hexagon head capscrews (24), cover (26), and gasket (25) from fan idler pulley (35). Discard
gasket (25).
(b)
Remove left hand threaded torque locknut (27), flat washer (28), hexagonal jam nut (31), plain washer
(32), fan idler arm (34), fan idler shaft (33), bearing assemblies (29), and oil seal (30) from the fan idler
pulley (35).
(c)
Remove capscrew (37), lockwasher (38), and pivot arm cap (39).
(d)
Remove capscrew (40), plain washer (41), pivot arm shaft (42), thrust washer (43), shaft bushings
(44),
and roll pin (45) from pivot arm (46).
(e)
Separate pivot arm (46), preformed packing (47), thrust washer (43), torsion spring (48), and pivot arm
support (49). Remove grease fitting (50) from pivot arm support.
(3)
Assemble fan Idler arm and pulley assembly (22) as follows'
(a)
Install new grease fitting (50) into pivot arm support (49).
(b)
Assemble torsion spring (48), thrust washer (43), new preformed packing (47), and pivot arm (46),
onto
pivot arm support (49).
(c)
Assemble shaft bushings (44), thrust washer (43), pivot arm shaft (42), and roll pin (45) and secure with
capscrew (40) and plain washer (41).
(d)
Install pivot arm cap (39) with capscrew (37), and lockwasher (38)
(e)
Assemble fan Idler arm (34) and fan idler shaft (33) with hexagonal jam nut (31) and plain washer (32).
(f)
Install bearing assemblies (29), and oil seal (30) into fan idler pulley (35) and mount onto fan idler shaft
(33). Secure with flat washer (28), and left hand threaded locknut (27). Tighten torque locknut to 145 to
155 pound-feet (197 to 210 newton-meters).
(g)
Install cover (26) and gasket (25) with hexagon head capscrew (24).
(h)
Attach fan idler arm assembly (23) to pivot am assembly (36) with ring dowel (21), lockwashers (20),
and hexagon head capscrew (19).
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