Pressure Control Adjustment
E
A
+
6.If the pressure is lower than 2750 psi (190 bar): Unplug the sprayer and relieve pressure. Insert the wrench through the hole (C) and tighten the adjust- ment nut (B) 1/8 turn or less. Repeat steps 5 and 6.
If the pressure is higher than 2750 psi (190 bar): Unplug the sprayer and relieve pressure. Insert the wrench through the hole (C) and loosen the pres- sure adjustment nut (B) 1/8 turn or less. Repeat steps 5 and 6. Repeat this procedure until the proper stall pressure is obtained.
7.Now check to see at what pressure the sprayer starts to run again after it stalls. Plug in the spray- er, turn it on, close the needle valve, and set the pressure at maximum. Allow the sprayer to run until it stalls.
D
B
C | TIGHTEN |
|
Fig. 22 | 68 | 0750 |
NOTE: Refer to Fig. 22 for the remainder of this procedure.
2.Remove the plug (68).
3.Open the needle valve slightly. Turn the pressure adjusting knob (A) to the minimum setting.
4.Plug in the sprayer and turn the switch (E) ON. Increase the pressure just enough to start the sprayer. Fully prime the hose, being sure to elimi- nate all air from the system.
5.Open the needle valve a just enough to allow the pump to run continuously, and turn the pressure adjusting knob to maximum. Very slowly start to close the needle valve. Observe the pressure at which the pump stalls, which should be approxi- mately 2750 psi (190 bar).
NOTE: In Step 8, the slower the pressure is raised, the easier it is to note the exact stall pressure. Closing the needle valve quickly causes the pressure to rise too fast which gives a false reading.
8.Open the needle valve very slowly while observing the pressure gauge. Check to see if the pressure drops to approximately 2350 psi (161 bar) before the sprayer starts again.
9.If the pressure is not approximately 2350 psi (161 bar): Shut off and unplug the sprayer, but do not relieve pressure. Turn the differential wheel (D) just one notch and repeat Steps 5 and 6. Check the pressure drop again, and repeat if necessary.
NOTE: If you adjust the differential wheel, recheck the stall pressure (steps 5 and 6) to be sure the it has not changed.
10.Relieve pressure. Flush the water out with mineral spirits. Relieve pressure. Install the plug (68). Remove the test equipment.
