housing. The clearance between rotors may be
bolts uniformly until gears are tight against the
established by moving one of the helical gears out
shoulders of shaft. Remove gear bolts, plain
or in on the shaft relative to the other gear. Moving
Washers and cloth.
gears "out" or "in" on the rotors is accomplished
(10) Place the pilot in the counterbore of gears
by adding or removing shims between gear hub and
and start the twelve point bolt in the right-hand
rotor shaft and start the hex head bolt in the left-
hand rotor shaft. Tighten the bolts to 25-30 ft-lb
(13) Measurements should be taken from both
the inlet and outlet sides of blower by inserting
feeler gage between housing (29) and rotors (32).
(11) Check the backlash between blower gears
Measurements should be taken across the entire
(12) After the blower rotors and gears have
length of each rotor lobe. Refer to table 1-1 for
been installed, the blower rotors must be timed.
Rotors, when properly positioned run with a slight
f. Installation. Installation is the reverse
clearance between the rotor lobes and with a slight
procedure of removal. Replace all gaskets.
clearance between the lobes and the walls of the