CAMCORP Blower Package with Sutorbilt Blower - Manual (Page 44)

SB-7-621 Page 31
These impeller-to-impeller and impeller-to-case clearances are extremely critical. Even though the
blower may turn freely by hand when cold, under operating conditions, the parts expand, and the
rotors are subject to slight defection.
If the clearances are not sufficient, the impellers may contact each other or the housing with
destructive results. If the clearances are too great, the blower may not develop the pressure or
airflow that is required to perform its function.
12. Impeller tip to case clearance should be checked at this time by inserting the correct thickness feeler gauge
between the tip and the case and rotating the impeller (see FIGURE 7-4, page 30). Repeat the procedure on
both impellers.
NOTICE
When checking the tip to case clearance, move the feeler gauge over the entire length of the impeller
to ensure that the tips do not bind along their length.
13. INSTALLING THE TIMING GEARS
A. Apply a light grease, or oil, on the shaft area where the timing gear will be positioned.
B. Place feeler stock in the amount of 1/3 of the total end clearance between drive headplate and both
impellers. This will stop the impellers from contacting the headplate while the gears are being driven on.
FIGURE 7-5
If installing gears on a blower containing mechanical seals, a press must be used to drive the gears
on the shafts. Blows from a hammer or mallet will damage the seal.
C. Secure the bearing retainer plate (12) to the gear headplate using capscrews (10). Refer to FIGURE
7-8, page 34, for torque specifications.
D. If reusing the timing gears, the gears should be returned to their original positions. Use taper pin holes
and matchmarks for correct positioning.
NOTICE
Replacement gears have minimum backlash marks on the outside diameter of the gear face. These
marks should be located 180 degrees from each other (see FIGURE 7-5).
E. Using the driving tool shown on page 23, drive one gear flush with the end of the shaft and re-ream the
original hole between the shaft and the gear if movement between the shaft and gear was negligible. If re-
reaming fails to eliminate edges set up by re-timing, drill a new hole approximately 90 degrees from the
original hole. Apply a thin coat of Loctite 620 to the taper pin and install the taper pin in the reamed hole
between the shaft and the gear. Control the depth of the taper pin leaving approximately 1/8 in, taper pin
protruding beyond the end of the shaft..