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CAH-SVX01A-EN 51
See “
ƽ
WARNING Hazardous
Voltage with Capacitors!” on
page 49 regarding
disconnection of power.
Fan Bearing Lubrication
CAUTION
Bearing Failure!
Do not mix greases with different
bases within the bearing. Mixing
grease within the bearing may result
in premature bearing failure.
The grease used in electric motor
bearings is usually not compatible
with the grease used in fan bearings.
Never mix the two grease types!
Note: Lubricate the bearing
according to the motor
manufacturer’s recommendations
and use the manufacturer-
recommended grease.
Refer to Table 6 for minimum torque
of motor mounting and bearings
bolts.
• Fan bearings without lubrication
lines are sealed bearings. Re-
lubrication is not required.
• Fan bearings equipped with
lubrication lines should be
lubricated with a lithium-based
grease that conforms to NLGI
No. 2 for consistency.
Compatible greases include:
– Texaco Multi Fak 2
– Shell Alvania 2
– Mobil 532
– Chevron Dura-Lith 2
– Exxon Beacon
– Keystone 84H
Table 6. Minimum hex head bolt
torque in lb.-ft. (Grade 5 bolts)
Size
(inches)
Thread
Designation
Minimum
Torque
1/4-20 UNC 6
1/4-28 UNF 7
65/16-18 UNC 14
5/16-24 UNF 16
3/8-16 UNC 24
3/8-24 UNF 28
7/16-14 UNC 42
7/16-20 UNF 45
1/2-13 UNC 69
1/2-20 UNF 83
9/16-12 UNC 99
9/16-18 UNF 118
5/8-11 UNC 150
5/8-18 UNF 176
3/4-10 UNC 254
3/4-16 UNF 301
7/8-9 UNC 358
7/8-14 UNF 422
1-8 UNC 500
1-14 UNF 602
Soft metric conversions are not acceptable for
screw and hex sizes.
Motor bearings are factory-
lubricated for normal life. In the case
of a double-shielded bearing, the
grease provided is that which is in
the bearing. To regrease motors
without grease fittings:
1 Remove the bearing brackets.
2 If the original bearing is to be
relubricated, remove the shield
opposite the rotor.
a Do not replace.
b Flush old grease from
bearing with suitable solvent.
3 Lubricate the bearing and add
grease to the bearing chamber.
The chamber should be three-
quarters full of grease. (An
alternate method is to replace
the old bearing with a new
double-shield pre lubricated
bearing.) See Table 7 for
maximum grease capacity.
Note: Lubricate the bearing
according to the motor
manufacturer’s recommendations
and use the manufacturer-
recommended grease.
4 Reassemble the motor.
Fan Motor Inspection
Inspect fan motors periodically for
excessive vibration or temperature.
Table 7. Fan bearing maximum grease
capacity
Shaft size
(inches)
Capacity
(fluid ounce)
1/2 - 3/4 1/7
7/8 - 1 3/16 3/8
1 1/4 - 1 1/2 5/8
1 11/16 - 1 15/16 7/8
2 - 2 7/16 1 1/4
2 1/2 - 2 15/16 2