Service Manual

SERVICE INSTRUCTIONS
3.11 REPLACE MOTOR (fig. 3.1 la, 3.1 1b)
When replacing the motor
it is necessary
to remove the automatic line feed assembly.
Refer to section
1 for head disassembly.
To remove the wire connectors, use wire
cutters and nip the connector in the center
of the factory crimp; pull the wires out.
Remove the roll pin by rigidly supporting
the armature shaft (to prevent bending)
and driving the roll pin out.
Figure 3.1
la
Figure 3.1 1 b
3.2
SPIN MOTOR BY HAND
Spin the motor with your hand and notice
the feel of the armature;
it should turn
freely. Visually check for excessive com-
mutator wear, armature end-play and bear-
ing to shaft
fit. A binding or scraping sound
when the motor
is turned could be evidence
of
a bad bearing or a deformed drum.
3.21
CHECK DRUM (fig. 3.21)
A deformed drum means that plastic de-
formation has occurred to the drum
at the
motor shaft. The drum may have slipped
up the motor shaft. A
tell-tale sign would
be the spool not located inside the drum
correctly. A deformed drum must be
replaced.
3.22
-
3.23
Deformed Correct
Figure 3.21
REPLACE DRUM (fig. 3.22)
SERIAL NOS. 800001 -899999.
A retaining ring
is used to secure the drum.
After removing the spool, driver, core and
spring
as described in section 1, pry out
the ring and slide the spool off the shaft.
Install with 1979 parts.
Figure 3.22
SERIAL NOS. 900101 and UP.
After removing the spool, driver, core and
spring, the drum will slide off the motor
shaft. Install the new drum and reassemble.
BAD BEARING - REPLACE MOTOR OR
TRIMMER (fig. 3.23)
To pin-point
a defective motor bearing,
inspect for
a burned or charred shaft at
the bearing. Carefully watch the bearing;
it should not spin in its casing. Lubricate
the bearing while turning the motor;
a
drop or two of 30 wt. oil may be all that
is needed to free-up the motor. If the
bearing
is at fault, replace the motor as per
section 2.1
1 or, replace the trimmer if
in warranty.
Figure 3.23
16