HMS
OPERATION
1A
1A-9
1.12 Periodic Maintenance
Before Operating
Inspect air filter and vent holes. Clean or replace dirty or clogged filters.
Inspect electrical cords for wear or damage. Do not use damaged cords.
Every 50 hours
Inspect brushes in motor.
Every 100 hours
Clean and lubricate core in shaft.
Every 300 hours
Change oil in head.
1.14 Motor Housing
Clean motor housing immediately after use, using a
damp cloth to remove dust or concrete. Inspect rear air
filter, front screen, and vents on motor housing to make
sure they are open. Replace or clean clogged air filter
before operating motor to prevent overheating.
To clean rear filter: screw out knob and remove cover
(d)
from motor. Remove filter
(e)
and wash in warm, soapy
water. Allow filter to dry completely before using.
1.13 Motor Brushes
To protect the motor, the brushes are designed to auto-
matically shut off the motor if they become too short. If the
motor stops during operation, the brushes may need to be
replaced. To avoid having the brushes shut down the
motor unexpectedly, inspect brushes every 50 hours and
replace them when necessary. Always replace both
brushes at the same time.
To inspect or replace brushes:
1. Remove brush caps
(a)
from both sides of motor.
2. Pull brushes
(b)
out and measure length. Install new
brushes if length
(c)
is less than 3/8" (10 mm) long. If
brushes are still long enough, place them back in
motor. Make sure they are installed in the same
positions they were removed, to avoid arcing.
3. Break in new brushes by running motor for about 5
minutes with no shaft attached.
c
a
b
1007SD06
d
e
1007SD05
