MAYCO ST-45HRM CE PUMP — OPERATION & PARTS MANUAL — REV. #0 (02/23/04) — PAGE 53
ST-45HRM CE CONCRETE PUMP— MAINTENANCE (PUMP)
ST45 PRESSURE SETTING SEQUENCE
To set
maximum
pump pressure:
1. With the engine turned “OFF”, loosen the 6.4 mm (1/4-
inch) hydraulic hose attached to the compensator valve
located on the top of the Main Delta Q Pump.
2. Loosen the
jam nut
located on the end of the compensator
valve (Figure 50).
3. Turn the
compensator adjustment nut
(Figure 50)
clockwise
until tight. Tighten the 6.4 mm (1/4-inch) hose
leading to the compensator.
4. Start the engine and loosen the jam nut located on the
maximum relief valve cartridge
(Figure 51).
5. Run the engine at maximum RPM (2,550) and turn the
volume control knob
counter-clockwise
to maximum
volume position (Figure 51).
Figure 50. Compensator Valve
MAXIMUM RELIEF
VALVE CARTRIDGE
JAM NUT
MAIN
RELIEF VALVE
VOLUME
CONTROL
Figure 51. Hydraulic Drive Pump Manifold
6. On the control box, turn the
pump control switch
(Figure
22) and the
test switch
(Figure 31) to the “ON” position.
Using an allen wrench, adjust the
main relief valve
(Figure
45) to 24.13 mPa (3,500 PSI). The reading can be taken
from the
pumping pressure gauge
(Figure 52).
7. Hold the main relief valve adjusting bolt with a wrench and
tighten the jam nut. Using the test switch, double check the
pressure reading to make sure the setting has not changed.
Figure 52. Pumping Pressure Gauge
8. Turn the engine off and loosen the hose from the
compensator valve. Loosen the jam nut and turn the
compensator adjustment nut
(Figure 50)
counter-
clockwise
½ turn. Tighten the 6.4 mm (1/4-inch) hydraulic
hose.
9. Start engine and run at maximum RPM with volume control
at maximum volume (fully
counter-clockwise
). Turn the
pressure test switch
(Figure 31) to the “ON” position.
The pumping pressure gauge should now read 22.75
mPa (3300 PSI). It may be necessary to repeat the above
steps to achieve the proper pressure settings. After the
adjustment, make sure the compensator valve jam nut is
locked tight.