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Operation Manual
9.4 Adjusting the rotor timing
1.
Slide rotors (13) onto the shafts (28,29),
but do not tighten the retaining nuts (9).
2.
Turn the shaft so that the rotors are in the
position shown below.
Shim
Tab washer
Gear locknut
Radial
Clearance
Mesh Clearance
(Make clearances
either side of the
lobe as near equal
as possible)
3.
With the rotors loose on the shafts, using
feeler gauges measure between the
point indicated (mesh) whilst squeezing
the lobes together. Turn the shaft as
required to measure all six positions.
4. If the measurement points are unequal,
note the difference and which side of the
rotor has the larger clearance.
5.
Correct the difference by adding or
removing shims (30) between the gear
face and shaft shoulder as indicated in the
diagram. Fully tighten the gear retaining
nuts and check the clearances are within
the specification limits. If correct, lock the
gear lock nuts (38) with the tab washer
(52).
6.
Remove the rotors.
9.5 Fitting the gear housing
1. Clean the gear housing (14) and heat to a
temperature of 158
0
F. Re-assemble the
bearing outers (39) into the housing. Allow
to cool to handling temperature then with
light lubrication to the outside diameter of
the oil seal (41) press into the housing.
2.
Ensuring that the faces of the bearing
housing and gear housing are clean, fit
new gasket (17) to bearing housing.
3. Carefully slide the gear housing over the
shaft ensuring the oil seal is not cut or
damaged. Tighten the socket head cap
screws (15) to a torque figure of 33 lbft.
STP125 Page 21