Page 17 - Technical Guide

P roSteering®

Relief
valve

Some
gears
are
equipped
with
a
relief
valve
to
limit
the

maximum
supply
pressure
from
the
power
steering
pump.

Knowing
whether
or
not
a
gear
is
equipped
with
a
relief
valve

is
useful
information
in
the
process
of
identifying
the
gear

part
number.

For
all
gear
types
the
relief
valve
is
typically
on
the
outboard

surface
of
the
valve
housing
casting.

The
Sheppard
type
relief
valve
is
a
1
½”
hex
with
a
raised

‘hood’
in
the
center
of
the
relief
valve.

The
TRW
type
relief
valve
is
a
7/8”
hex
head.

The
TRW
type

relief
valve
does
look
similar
to
the
steel
plugs
used
in
a
4
line

gear
without
an
auxiliary
assist
gear.

These
auxiliary
port

plugs
are
a
5/8”
hex
head.

150416_TECHNICAL
GUIDE
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