MASSEY FERGUSON 5400 - 3-Position SA; da Spool Valve with Non-Return Valve and Automatic Return

Massey Ferguson 5400 - Issue 1.b
09E01.18
Auxiliary spool valve
G . 3-position SA / DA spool valve
with non-return valve and auto-
matic return
The operation of this spool valve is identical to those
explained previously.
Operation of the non-return valve (Fig. 14)
When the spool (2) is moved upwards, the oil coming
from channels (N) and (P) is directed to outlet (B) by
lifting the non-return valve (3) which supplies the slave
device.
In the neutral position, the non-return valve ensures
the oil tightness of the circuit.
When the spool is moved upwards, the oil coming
from the channels (N) and (P) lifts the valve (1). It is
then directed to an internal channel via grooves
machined on the spool, and supplies the slave device
via the outlet (A).
The movement of the spool shifts the pushrod (4). This
raises the ball, causing a drop in pressure on the slave
device side, which allows the valve (3) to rise from its
seat and oil to flow through to the channel (R).
I
MPORTANT: During disassembly of the spool (2), it is
essential to first disassemble the non-return valve (3)
and pushrod (4).