Graco LineLazer II 3900 Instructions Manual page 14

Removal
1.
Relieve pressure; page 5.
2. Fig. 15. Remove five screws (307) and
cover (322).
3. Disconnect at control board (302):
D Four clutch leads: two violet and two black.
D Lead (D) from potentiometer.
D Lead (E) from transducer.
D Two red leads (A) to ON/OFF switch (309).
4. Remove four screws (303), green ground wire, and
control board (302).
Removal
1.
Relieve pressure; page 5.
2. Fig. 15. Remove five screws (307) and
cover (322).
3. Disconnect lead (E) from control board (302).
4. Remove three screws (319) and filter housing
(318) from control plate (301). Carefully pull
transducer connector through rubber grommet
(315).
Removal
1.
Relieve pressure; page 5.
2. Fig. 15. Remove five screws (307) and
cover (322).
3. Disconnect lead (D) from control board (302).
4. Loosen set screws on potentiometer knob (313)
and remove knob, shaft nut, lockwasher (310) and
pressure adjust potentiometer (310).
5. Remove seal (311) from potentiometer (310).
14 308874
Pressure Control
Control Board
Pressure Control Transducer
Pressure Adjust Potentiometer
Installation
When installing replacement control board, follow
instructions with control board to set model type.
1. Fig. 15. Install control board (302) with five
screws (303).
2. Connect control board (302):
D Two red leads (A) to ON/OFF switch (309).
D Lead (E) to transducer.
D Lead (D) to potentiometer.
D Four clutch leads: two violet and two black.
3. Install cover (322) with five screws (307).
5. Remove pressure control transducer (318z) and
packing o-ring (318aa) from filter housing (318).
Installation
1. Fig. 15. Install packing o-ring (317) and pressure
control transducer (316) in filter
housing (318). Torque to 30–35 ft-lb.
2. Carefully feed transducer connector through
rubber grommet (315). Install fluid filter (318) on
control plate (301) with three screws (319).
3. Connect lead (E) to control board (302).
4. Install cover (322) with five screws (307).
Installation
1. Fig. 15. Install seal (311) on potentiometer (310).
2. Install potentiometer (310), shaft nut, lockwasher
(310), and potentiometer knob (313).
a. Turn potentiometer shaft (310) clockwise to
internal stop. Assemble potentiometer knob
(313) to strike pin on plate (312) and have
bottom of knob clear plate by .040 to .060 in.
b. After adjustment of step a., tighten both set
screws in knob 1/4 to 3/8 turn after contact
with shaft.
3. Connect lead (D) to control board (302).
4. Install cover (322) with five screws (307).