Manual 2017 Rev C p/n 2017
36
08
Disassembly and Reassembly
Adjusting Rotor Interlobe Clearance
1. Use feeler gauges to take interlobe readings,
and record them on each side of housing as
indicated in
Figure 8-15
. As shim is removed
or added behind the helical gear, the gear
rotates as it is moved in or out and the driven
rotor turns with it, thus changing the clearance
between rotor lobes.
Figure 8-15 – Checking Rotor Interlobe Clearances
2. Changing the shim thickness will change the
rotor lobe clearance.
3.
To determine the amount of shim to add or
remove, subtract the smaller value from the
larger value.
EXAMPLE:
Referring to
Figure 8-15
, check
the clearance at AA (right-hand reading) and
BB (left-hand reading). If the AA reading is
0.009 in. (0.23 mm) and the BB reading 0.003
in. (0.08 mm), adjust by removing 0.006 in.
(0.15 mm) shims from the driven rotor. The
readings will change one half the amount
removed: 0.003 in. (0.08 mm). AA should then
read 0.006 in. (0.15 mm) and BB should read
0.006 in. (0.15 mm). The
¿
nal readings should
be within 0.002 in. (0.05 mm) of each other.
