Hydraulic System; Hydraulic Hygiene; Hydraulic Oils; Rectify Oil Leaks - Husqvarna Rider 316T/s AWD Workshop Manual

Hydraulic System

Hydraulic Hygiene

Keep the hydraulic system clean. Remember to:
• Clean thoroughly before opening the filler cap
or disconnecting anything.
• Use clean vessels with topping up oil.
• Use only clean oil that has been stored in
sealed containers.
• Do not reuse drained oil.
• Change oil and filters according to the
intervals given in "Service Schedule".
A system that is contamination-free is required to
give a functioning hydraulic system without
shutdowns. Particles are generated during
operation that can cause both wear damage and
malfunctions. The system has filters to separate
these particles. The filter is dimensioned to trap the
generated particles, but if dirt enters the system
from outside the filters will rapidly clog so that they
do not work as intended. If there is dirt in the
system, further contaminants will be generated,
creating a vicious circle. This will result in
breakdowns and the need for large resources to
clean the system.
The particles that cause the most damage are the
same size as the play between the moving parts
and the components. Normal play in pumps and
valves are from 3-5 µm and up (1 µm = one
thousandth of a mm). In connection with this, it can
be noted that one particle of size 40 µm can only
just be seen with the human eye.
Particles formed during operation or that enter the
system during repair work and service usually
comprise the following:
• Wear produce from components, mainly those
that have moving parts such as pumps and
engines.
• Dust that enters through the hydraulic tank
breather.
• Water that forms due to condensation. (Water
vapor enters with the breath.)
• Sludge, etc., from the degradation of oil.
• Products of corrosion from the system due to
late oil changes resulting in water and other
aggressive substances in the oil.
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HyDrAuLiC SySTEM
• Dirt particles entering the system during
intervention:
- Contaminants following with filled oil.
- Particles of dust from the repair premises.
- Gasket and thread seal from assembly.
- Dirt from storage and handling prior to
assembly.
- Fiber from rags, filters, etc.
- Dirt from the place of entry due to deficient
cleaning prior to dismantling.
- Dirt and dust that enters the system from
dirty protective plugs.
Water, even in small amounts, causes rusting of
ground surfaces, especially if the system is not
used and contributes to the formation of sludge
products. These products clog the filters causing
circulation problems and cavitation in the pump.
Small fibers and threads from wipes or clothes can
mat together in jet screws and restrictors. Fibers
themselves do not do much harm but a collection
of them can cause a blockage and increase wear
on system components.
Each particle of dirt is an abrasive that generates
more contaminants, which will eventually result in
permanent damage. The number of particles will
increase each time the hydraulic system is opened.
After a few hours in operation most of the particles
that have entered are trapped in the filters.
Therefore, avoid opening the hydraulic system
unless really necessary because each intervention
increases the risk of contamination even when the
work is carried out in a professional manner.

Hydraulic Oils

Oil is at teat as important as any other part of a
hydraulic system. It has been noted that around
70% of all hydraulic problems are sourced from the
use of unsuitable types of oil or that oils containing
dirt or other contaminants have been used in the
system.
The majority of contaminants in oil are usually dirt
that has entered the system from outside.

rectify Oil Leaks

Cavitation is caused by air entering can cause
internal damage to pumps and engines. Air can
enter the system where there is an oil leak. That is
why it is so important that oil leaks are rectified as
soon as possible.