Graco B Series Instructions-Parts List Manual page 17

Spin Test
WARNING
To reduce the risk of serious bodily injury, includ-
the skin, or injury from moving parts, always follow
ing fluid injection or splashing in the eyes or on
the Pressure Relief Procedure Warning on page
2 before checking, adjusting, cleaning and shut-
ting down the sprayer.
I
I
For checking armature, motor winding and brush
electrical continuity.
Setup
1.
Remove the drive housing from the sprayer
as
described in
DRIVE HOUSING
REPLACEMENT,
Steps
1-7,
page 20.
2. Remove the pressure control cover
(48)
and
cover (F), and the inspection covers
(J).
See Fig.
screws (79). Remove the motor cover (I), the fan
8.
3. Disconnect the
two
leads from the motor to the
bridge
(308).
See Fig.
9.
1.
2.
Armature Short Circuit Test
Fig. 8
m i
. .
. .
Quickly turn the motor fan by hand; If there are no
shorts, the motor will coast two or three revolu-
tions before coming to a complete stop.
If the motor does not spin freely and resists rota-
tion, the armature is shorted and the motor must
be replaced. See page 30.
Armature, Brushes, and Motor Wiring
Open Circuit Test (Continuity)
1.
Connect the
two
black motor leads together with
a test lead.
2. Turn the motor
fan
by hand at about
two
revolu-
tions per second.
.3. If there is uneven or no turning resistance, check
the following and repair parts
as
needed. See
page 32.
a. broken brush springs
b. 'broken brush leads
c. loose brush terminal screws
d. wom brushes
e.
broken motor leads
f. loose.motor lead terminals
4. If
there is still uneven or no turning resistance,
replace the motor. See page
34.
Fig. 9
t x b
307-889 17