
9
POWER UNIT REASSEMBLY:
Apply a thin film of grease to both sides of gasket 382492.
Assemble handle subassembly to governor housing subas-
sembly with the gasket between. Secure with two screws
382524 .
MOTOR:
Measure the length of the cylinder 629324. Size four rotor
blades 625577 .005 inches shorter than the cylinder.
Measure the length of the cylinder and the length of the body
of the rotor. Subtract the rotor body length from the cylinder
length and divide the difference by two. This is the rotor end
clearance.
Install bearing 847095 in rear bearing plate 629325. Lightly
load the inner race of the bearing. Using a depth micrometer,
measure the distance from the flat face of the bearing plate to
the inner race. Add the rotor end clearance to get the rotor
collar thickness. Select the rotor collar that most closely
matches the calculated thickness.
Rotor Collar Thickness Part Number
.1850 869260
.1860 869261
.1870 869262
.1880 204778
.1890 843913
Place the rotor collar selected on the threaded end of the rotor
with the large chamfer facing the rotor body. Install set screw
867086 in rotor with hex into hole first. For the 1100 rpm motor
(380 rpm spindle) and the 230 rpm motor (75 rpm spindle) the
set screw must be inserted normally.
Insert the governor stem 629329 into governor spider 865686
from the non-threaded end. Place the two governor weights
865663 in the spider slots and insert twogovernor weight pins
867388. Press the two lock pins 864821 in the small holes to
retain the weight pins.
Place the rear bearing plate with the bearing in place on the
threaded end of the rotor. Install Rotor collar 843913, to act as
a spacer, and the Reversing Valve 629327 (with the small
pocket facing away from the bearing plate) against the rear
bearing plate. Insert the governor spring 867084 into the rotor.
Screw the governor assembly onto the rotor and tighten.
Lubricate the rotor blades with 10 wt. oil and insert them into
rotor slots. Slide cylinder 629324 over the rotor and insert the
alignment pin in the cylinder into the hole in the rear bearing
plate.Install front bearingplate864235 and pressfrontbearing
844772 into place. While lying in a V-block, the rotor should
turn with no indication of dragging or rubbing.
POWER UNIT ASSEMBLY:
Insert the motor, governor end first, into the governor housing.
The reversing valve should lie on the large retaining ring in the
housing bore, and the pin in the reversing piston should
engagethe small pocketonthe face ofthereversing valve. The
alignmentbutton on therear bearing plateshouldfit in thesmall
cutout at the top of the governor housing bore.
Slide the motor housing 629319 over the motor. Align the pin
inthe motor housingto the holeinthe governor housing.Clamp
the motor housing to the governor housing using clamp nut
629318.
Install two muffler elements 629323 in exhaust deflector
629322, covering the exhaust slots. Install two muffler ele-
ments 203632 inside of the 629323 elements. Of the three
cavities in the exhaust deflector, the middle one remains
empty. Install 0-ring 617754 in the groove. Slide the exhaust
deflector over the motor.
REASSEMBLE AND INSTALL THE GEAR TRAIN:
fOR THE 4200rpm, 3000rpm and 620rpm power units, the
pinion gear 864239 must be installed in the spider before the
idler gears. Plug the right angle fitting and run the power unit.
The output RPM should be no more than 10% above or below
the rated speed. Adjust governor if necessary. For 1100 rpm
motor (380 rpm spindle) and 230 rpm motor (75 rpm spindle),
the power unit must be disassembled and the governor re-
moved to adjust the set screw. Turn the screw counterclock-
wise to increase motor speed, and clockwise to decrease
motor speed. For all other power units,remove the gear train
and use a long Allen wrench to turn the governor set screw.
Turn the screw clockwise to increase motor speed, and
counter clockwise to decrease motor speed.
RAPID ADVANCE OVERLOAD CLUTCH ASSEMBLY:
Insert two 616503 bushings into 629312 spindle (The bush-
ings might be slight press fits in the spindle.) Lubricate the
large spline on the spindle and install 382536 Clutch Jaw. The
clutch jaw should slide freely. Install 629309 driving clutch jaw
and secure with 629310 retaining pin. Pin should sit flush with
or slightly below the spindle surface. Install 204349 spring,
852264 washer and 867924 retaining ring. With the spline
clamped in a vise, use a torque wrench to turn the hex on the
driving jaw. The clutch should trip between 3 and 5 inch
pounds. If the clutch torque is too light, disassemble the unit
and press the shaft of the driving jaw in to shorten its length by
.020 inches. Install 203339 Belleville Spring Washer over the
small spline of the clutch spindle with the dished side towards
the clutch.
Thread 629307 Positioning Ring onto 629302 Clutch Housing
with the holes in the ring towards the smaller threads.
If the subassembly is to be checked into stock or sent out as
spare parts, place both components in a plastic bag to keep
them together.
RIGHT ANGLE HEAD ASSEMBLY:
BOTTOM COVER PLATE:
Install bearing 622400 in the large bore of the right angle head
cover 629343. Press the bearing 847609 into the differential
drive gear 629367. Insert gear post 629365 into the bore of the
bearing and press the post into the housing cover. Press the
spindle drive gear 622950 into the bore of bearing 622400.
Pressthe idler gear post 629359 intothehead cover. Insert the
signal valve shaft 629355 and the spring 867895 into the
angled bore of the head cover. Install plug 843434. Insert
bearing 847609 into the small bore at the end of the plate.