LR3/Disco 3
The fluid reservoir is located on a bracket in the left hand side of the engine compartment, behind the radiator. The
reservoir comprises a body, cap and filter. The purpose of the reservoir is to contain a surplus of the hydraulic fluid in the
system to allow for expansion and contraction of the fluid due to temperature variations. The fluid level ensures that the
supply connection on the bottom of the reservoir is covered with fluid at all operating vehicle attitudes. Any air which is
present in the system is exhausted from the system in the reservoir.
The body is a plastic moulding with two ports at the bottom which provide for the connection of the suction supply and
return hoses. Moulded markings on the side of the reservoir denote the upper and lower fluid levels. A non-serviceable,
100 micron nylon mesh filter is fitted in the body. The filter removes particulate matter from the fluid before it is drawn into
the pump supply connection.
The cap is rotated counterclockwise for one quarter turn to release from the body. The cap is fitted with an O-ring to
prevent fluid leakage. The cap incorporates a breather hole to allow for changes in fluid level during operation and
prevent vacuum or pressurisation of the reservoir.
HIGH PRESSURE HOSE
The high pressure hose connecting the pump to the steering gear valve unit contains two attenuators. Each attenuator
comprises a bullet shaped restrictor which is secured inside the hose. The restrictors damp pressure pulses from the
pump, consequently reducing noise and strain on downstream components. The attenuators are an integral part of the
hose and cannot be serviced separately.
FLUID COOLER
The fluid cooler is located in the return line from the steering gear to the reservoir. The cooler comprises a flexible hose
and a solid pipe which connect between the reservoir and the return pipe from the steering gear. The cooler is an integral
part of the pipe and cannot be replaced as a separate component.
The cooler is a fabricated aluminium tube, through which the power steering fluid passes. The outer diameter of the
cooler tube has aluminium loops attached to it which dissipate heat. Cool air entering the front of the vehicle passes over
the cooler and flows through the loops. The loops act as heat exchangers, conducting heat from the fluid as it passes
through the tube.
