COOK ETS - Manual (Page 5)

5
Changing Shaft Speed Continued
b. 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.
c. 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 main-
tained.
Pulley and Belt Replacement
a. Clean the motor and fan shafts.
b. Loosen the motor plate mounting bolts to relieve the
belt tension. Remove the belt.
c. Loosen the pulley setscrews and remove the pulleys
from the shaft.
If excessive force is required to remove the pul-
leys, 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
replacement if it is more than 0.020 inch out of
true.
d. Clean the bores of the pulleys and place a light coat of
oil on the bores.
e. Remove grease, rust and burrs from the shaft.
f. 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 respective shafts.
g. After the pulleys have been correctly placed back onto
their shafts, tighten the pulley setscrews.
h. Install the belts on the pulleys. Align and adjust the
belts to the proper tension as described in Belt and Pul-
ley Installation, page 2.
Bearing Replacement
The fan bearings are pillow block ball bearings.
a. Remove the top cap to gain access to the fan.
b. Loosen the motor plate mounting bolts and remove the
drive belts.
c. Remove the propeller from the shaft.
d. Remove the four (4) bearing hold-down bolts and then
remove the shaft and bearings from the fan as an
assembly.
e. Measure and record the location of the bearings on the
shaft. This will aid the reassembly.
f. Loosen the bearing setscrews and remove the bear-
ings from the shaft.
g. Remove any imperfections in the shaft using a smooth
file or emery cloth.
h. Place new bearings on the shaft.
i. Locate one of the bearings using the previous mea-
surements and tighten one setscrew.
j. Install the propeller on the shaft. Center the propeller in
the opening and tighten the bearing bolts.
k. Rotate the propeller to allow the bearings to find their
center of free movement.
l. Align the bearing setscrews and tighten to proper
torque. Refer to the Torque chart on page 2.
m. Reassemble drive assembly and replace top cap.
Propeller and Shaft Replacement Precautions
• If the shaft is dropped and bent, it may cause unbal-
anced operation of the fan.
• When handling the propeller separately from the shaft,
place a support through the hub for lifting, making sure
not to injure the finished bore of the propeller.
• Never allow the propeller to rest its entire weight on the
blades. The propeller and shaft can be lifted by slings
around the shaft on each side of the propeller so the
propeller is supported by its hub.
• If using a chain to lift the propeller, make sure there is
sufficient padding on the shaft and propeller. This pre-
vents the scoring of the shaft or injury to the propeller.
The chain or cable should be spread with timbers, or
braced by some other method to prevent damage to the
propeller side plates.
Maximum RPM
AQB
Size
Maximum
RPM
SEP
Size Maximum
RPM
ETE/
ETS
Maximum
RPM
24 1025 24 1150 24 1160
30 850 30 850 30 930
36 725 36 725 36 780
42 625 42 610 42 665
48 575 48 565 48 660
54 640
60 615