Pressure Control Adjustment - Graco LineLazer GM 3500 Manuel D'instructions

Pressure Control Adjustment

Use extreme caution when performing this calibra-
tion procedure to reduce the risk of a fluid injection in-
jury or other serious bodily injury, which can result from
component rupture, electric shock, fire, explosion or
moving parts.
This procedure sets the sprayer to 2600–3000 psi
(180–207 bar, 18.0–20.7 MPa) Maximum Working
Pressure.
Perform this procedure whenever the pressure control
assembly is removed and reinstalled, or replaced, to be
sure the sprayer is properly calibrated.
Improper calibration can cause the sprayer to over–
pressurize and result in component rupture, fire or ex-
Service Tools Needed:
New 50 foot (15.2 m), 3000 psi (210 bar, 21.0 MPa),
flexible nylon airless spray hose, Part No. 223–541
0–5000 psi (0–345 bar, 34.5 MPa)
fluid–filled pressure gauge,
Part No. 102–814
New spray tip, size 0.025 to 0.029
3/8 in. ignition wrench or nut driver
5 gallon pail of water or mineral spirits
Swivel, 156–823
Nipple, 162–453
Tee, 104–984
Set Up
1. Follow the Pressure Relief Procedure Warning on
page 7.
2. Set up the system as shown in Fig. 25.
Set the Dead Band (Pressure Differential)
1. Remove the pressure control cover.
NOTE: Do not alter this adjustment if the wheel is already
set as shown in Fig. 26.
2. Set the white differential wheel (A) on the micro-
switch. Turn the wheel so the letter F is concealed
behind the switch and the letter E is the first letter
seen.
Pressure Up
1. Start the sprayer and prime it.
2. Adjust the pressure to 2600 psi (180 bar, 18.0 MPa).
3. Shut off the engine. If the pressure drops after the en-
gine is shut off, replace the pump packings before
proceeding. See 307–806.
Adjust the Pressure
1. Remove the plug (320) in the bottom of the control.
2. Turn and hold the pressure control knob (B) at the
maximum pressure.
3. Engage the nut (C): Insert the nut driver through the
pressure control hole (D), or use an ignition wrench
inserted from the front of the pressure control.
WARNING
See Fig. 27.
plosion. It may also prevent the sprayer from obtaining
the maximum working pressure, resulting in poor
sprayer performance.
NEVER attempt to increase the fluid outlet pressure by
performing these calibrations in any other way. Never
Exceed 3000 Psi (207 Bar, 20.7 MPa) Maximum
Working Pressure. Normal operation of the sprayer at
higher pressures could result in component rupture,
fire or explosion.
ALWAYS use a new 50 foot (15.2 m) spray hose, rated
for at least 3000 psi (207 bar, 20.7 MPa) Maximum
Working Pressure, when performing this procedure. A
used, under–rated hose could develop a high pressure
leak or rupture.
Fig. 25
Inside pressure
control looking up
at differential wheel
A
Fig. 26
D
320
C
Fig. 27
a. Loosen the nut just until you hear a click. Stop.
b. Slowly tighten the nut just until another click is
heard. Stop.
4. Replace the plug (320) and the pressure control
cover.
102–814
156–823
104–984
162–453
223–541
0035
0036
B
0037