Series 90 Axial Piston Pumps Technical Information Features and options MULTI-FUNCTION VALVES (continued)
Multifunction valve, pressure limiter, pressure regulation, option 1
To control Multifunction valve
M3
A
M1 M4
A
Servo piston
Bypass hex adjustment
Port A
M5
B
M
Servo pressure relief valves
Port B
C
Charge pressure relief valve
Servo piston
M2 B S
L2
Multifunction valve
P102 007E
Bypass Function In some applications it is desirable to bypass fluid around the variable displacement pump when pump shaft rotation is either not possible or not desired. For example, an inoperable vehicle may be moved to a service or repair location or winched onto a trailer without operating the prime mover. To provide for this, Series 90 pumps are designed with a bypass function. The bypass is operated by mechanically rotating the bypass hex on both multifunction valves three (3) turns counterclockwise (CCW). This connects working loop A and B and allows fluid to circulate without rotating the pump and prime mover. C Caution Possible pump and/or motor damage Bypass valves are intended for moving a machine or vehicle for very short distances at very slow speeds. They are NOT intended as tow valves.
18
250 - 123
520L0603 • Rev FB • July 2007
