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LO-PRO IO&M
B51021-004
For best results, lubricate the bearing while the fan is in
operation. Pump grease in slowly until a slight bead forms
around the bearing seals. Excessive grease can damage seal
and reduce life through excess contamination and/or loss of
lubricant.
In the event that the bearing cannot be seen, use no more
than three injections with a hand operated grease gun.
Motor Bearings
Motors are provided with prelubricated bearings. Any lubri-
cation instructions shown on the motor nameplate supersede
instructions below.
Conditions Chart
RPM
Temp. °F
Greasing Interval
Up to 1000
-30 to 120
3 months
120 to 200
1 month
1000 to 3000
-30 to 120
1-1/2 months
120 to 200
2 weeks
Over 3000
-30 to 120
2 weeks
120-200
1 week
Any Speed
< -30
Consult Factory
Any Speed
> 200
1/2 week
For moist or otherwise contaminated installations, divide the interval by a
factor of 3.
Direct Drive 1050/1075,1200,1300 &1500 rpm units use a
prelubricated sleeve bearing that has a oil saturated wicking
material surrounding it. The initial factory lubrication is ade-
quate for up to 10 years of operation under normal conditions.
However, it is advisable to add lubricant after 3 years. Use
only LIGHT grade mineral oil or SAE 10W oil up to 30 drops.
If the unit has been stored for a year or more it is advisable
to lubricate as directed above. For VCR direct drive units and
other units in severe conditions, lubrication intervals should be
reduced to half.
Motors without sleeve bearings (as described above) will
have grease lubricated ball or roller bearings. Motor bearings
without provisions for relubrication will operate up to 10 years
under normal conditions with no maintenance. In severe ap-
plications, high temperatures or excessive contaminates, it is
advisable to have the maintenance department disassemble
and lubricate the bearings after 3 years of operation to prevent
interruption of service.
For motors with provisions for relubrication, follow intervals
of the following table.
Relubrication Intervals
Service
Conditions
Nema Frame Size
Up to and
Including 184T
213T-365T
404T and Larger
1800
RPM &
Less
Over
1800
RPM
1800
RPM &
Less
Over
1800
RPM
1800
RPM &
Less
Over
1800
RPM
Standard 1-1/2 yrs. 3 months
1 yr.
3 months 6 months
1-1/2
months
Severe
6 months
1-1/2
months 6 months
1-1/2
months 3 months 2 weeks
Motors are provided with a polyurea mineral oil NGLI #2
grease. All additions to the motor bearings are to be with
a compatible grease such as Exxon Mobil Polyrex EM and
Chevron SRI.
Maximum RPM
LPB
Size
Maximum RPM
Standard Reinforced
100
3320
-
120
2755
-
135
2481
-
150
2051
-
165
1832
1971
180
1608
1754
195
1428
1758
210
1270
1507
225
1143
1319
LPB
Size
Maximum RPM
Standard Reinforced
245
1011
1335
270
871
1154
300
835
1121
330
713
963
365
623
884
402
538
746
445
462
739
490
357
682
540
345
581
Motor Services
Should the motor prove defective within a one-year period,
contact your local Loren Cook representative or your nearest
authorized electric motor service representative.
Changing Shaft Speed
All belt driven H-Series fans with motors up to and including
5HP are equipped with variable pitch pulleys. To change the
fan speed, perform the following:
1. Loosen setscrew on driver (motor) pulley and remove key,
if equipped.
2. Turn the pulley rim to open or close the groove facing. If
the pulley has multiple grooves, all must be adjusted to
the same width.
3. After adjustment, inspect for proper belt tension.
Speed Reduction
Open the pulley in order that the belt rides deeper in the
groove (smaller pitch diameter).
Speed Increase
Close the pulley in order that the belt rides higher in the
groove (larger pitch diameter). Ensure that the RPM limits of
the fan and the horsepower limits of the motor are maintained.
Replacing Pulleys and Belts
1. Clean the motor and fan shafts.
2. Loosen the motor plate mounting bolts to relieve the belt
tension. Remove the belt.
3. Loosen the pulley setscrews and remove the pulleys from
the shaft.
If excessive force is required to remove the pulleys, a three-
jaw puller can be used. This tool, however, can easily warp a
pulley. If the puller is used, inspect the trueness of the pulley
after it is removed from the shaft. The pulley will need replace-
ment if it is more than 0.020 inch out of true.
4. Clean the bores of the pulleys and place a light coat of oil
on the bores.
5. Remove grease, rust and burrs from the shaft.
6. Place fan pulley on the fan shaft and the motor pulley on
the motor shaft. Damage to the pulleys can occur when
excessive force is used in placing the pulleys on their re-
spective shafts.
7. After the pulleys have been correctly placed back onto
their shafts, tighten the pulley setscrews.
8. Install the belts on the pulleys. Align and adjust the belts
to the proper tension as described in
Belt and Pulley In
-
stallation
, page 2.