Kubota WSM B2050 Workshop Manual page 358

B2050, B2350, B2650, B3150, WSM
Down
(1) Boom Control Section
(2) Bucket Control Section
(3) Spool
(4) PB Passage 1
1. When the hydraulic control lever is set to the "DOWN" position, the spool (3) moves to the right, which forms oil
passages between passage 1 (7) and A1 port, and between B1 port and PB passage 1 (4).
2. As the oil passage from the neutral passage 1 (5) to the PB passage 1 (4) is closed by the spool (3), the
pressure-fed oil from the P port opens the load check valve (6) and flows through the notched section of the spool
(3) and A1 port to retract the boom cylinder (8).
3. Return oil from the boom cylinder (8) flows from the B1 port through the passage in the spool (3) and PB passage
1 (4) to the bucket control section (2).
(5) Neutral Passage 1
(6) Load Check Valve
(7) Passage 1
(8) Boom Cylinder
P: P Port
T: T Port
8-M15
HYDRAULIC SYSTEM
A1: A1 Port (To Boom Cylinder)
B1: B1 Port
(From Boom Cylinder)
PB: PB Port
a: Low Pressure
b: High Pressure
9Y1210982HYM0018US0
KiSC issued 03, 2014 A