5
CV IO&M
B51161-003
Bearing Replacement
The fan bearings are flange ball bearings.
1. Loosen the motor plate adjustment bolts, then slide
the motor plate so the belt will easily slip off.
2. Remove the driven pulley by loosening the setscrew.
3. Separate the outer housing halves.
4. Remove wheel, then loosen the setscrews on the hub
that holds the shaft and remove the hub plate. (Refer
to hub removal instructions below.)
5. Remove the bolts next to the straightening vanes and
pull the inner housing out.
6. Loosen the bearing setscrews and hold-down bolts,
then slide shaft out.
7. Sand the burrs on the shaft where the setscrews were
located.
8. Slide new bearings onto the shaft to the desired lo-
cation and loosely mount bearings onto the bearing
support. Bearing bolts and setscrews should be loose
enough to allow shaft positioning.
9. Replace the hub plate and wheel, align properly and
then tighten bearing hold-down bolts securely to the
bearing supports.
10. Align setscrews bearing to bearing and secure tightly
to the shaft.
Never tighten both pairs of setscrews before securing
bearing mounting bolts. This may damage the shaft.
11. Reassemble the unit.
12. Inspect the wheel position again. If necessary, read-
just by loosening the bearing bolts and setscrews and
repeat from step 5.
Hub Removal
1. Drill two 1/4” diameter holes, 180
°
apart centered ap-
proximately between the shaft and the outside diam-
eter of the hub, 3/8” to 1/2” in depth.
2. Tap 1/4” holes to 5/16” thread with a 5/16” hole tap. Do
not drill or tap greater than recommended.
3. Screw the puller arms to the full depth of the threads
into the tapped holes. Align center of the puller with
the center of the shaft. Ensure all setscrews in the
hub, normally two, are fully removed.
4. Slowly remove wheel from the shaft.
Recommended Puller
Lisle No. 45000 Steering Wheel Puller. This puller is
available at most automotive parts retail outlets.
Motor Services
Should the motor prove defective within a one-year pe-
riod, contact your local Loren Cook representative or your
nearest authorized electric motor service representative.
Changing Shaft Speed
All belt driven Propeller Wall fans with motors up to and
including 5 HP 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. Open or close the groove facing to change the pitch
diameter.
Speed Reduction
Open the pulley in order that the belt rests deeper in the
groove.
Speed Increase
Close the pulley in order that the belt rests higher in the
groove. Ensure RPM limits of the fan and the horsepow-
er limits of the motor are maintained.
3.
Retighten pulley setscrew on one of the flat areas of
the motor shaft.
4. After the adjustment is made, check for proper belt
tension. See the
Belt and Pulley Installation
section.
Pulley and Belt Replacement
1. Remove pulleys from their respective shafts.
2. Clean the motor and fan shafts.
3. Clean bores of pulleys and coat the bores with heavy oil.
4. Remove grease, rust, or burrs from the pulleys.
5. Clean the bores of the pulleys and place a light coat of
oil on the bores.
6. Remove burrs from shaft by sanding.
7. Place fan pulley on fan shaft and motor pulley on its shaft.
Do not hammer the pulleys onto the shafts because
this may damage the bearings.
8. Tighten in place.
9. Install belts on pulleys and align as described in the
Belt and Pulley Installation
section.
Recommended Torque for Setscrews/Bolts (IN-LB)
Setscrews
Hold Down Bolts
Size
Key Hex
Across
Flats
Recommended
Torque
Size
Recommended
Torque
Min.
Max.
#8
5/64”
15
21
3/8”-16
324
#10
3/32”
27
33
1/2”-13
780
1/4
1/8“
70
80
5/8”-11
1440
5/16
5/32”
140
160
3/4”-10
2400
3/8
3/16”
250
290
7/8”-9
1920
7/16
7/32”
355
405
1”-8
2700
1/2
1/4“
560
640
1-1/8”-7
4200
5/8
5/16”
1120
1280
1-1/4”-7
6000
3/4
3/8”
1680
1920
-
-
7/8
1/2”
4200
4800
-
-
1
9/16”
5600
6400
-
-
