come to rest it is advisable to recheck belt tension and
adjust if necessary.
11.12 Hydraulic circuit
CAUTION.
Never attempt to maintain the
hydraulic circuit unless the PTO has been
disengaged, the engine has been stopped, the key
removed and the machine come to rest.
CAUTION.
The hydraulic pump is driven from the
drive to the mill rotor and means that the pump will
continue to operate until the machine comes to rest.
CAUTION.
If the machine has been operating
then the hydraulic oil and components will be hot,
allow time for the system to cool before working on the
hydraulic circuit.
11.13 Hydraulic oil reservoir
All machines are delivered from the factory filled with
hydraulic oil. With the machine on level ground and
attached to tractor the oil level in the reservoir should
be between the minimum and maximum marks on the
sight gauge on the right hand side of the tank.
Only a good quality ISO HV46 grade hydraulic oil
should be used. Total capacity of the tank is
approximately 150 litres (33 gallons).
When filling the tank make sure the strainer inside the
filler cap is in place.
11.14 Hydraulic oil change and suction filter
The most accurate way of determining when the oil
needs replacing is to undertake an oil analysis to check
if the base oil has degraded or if the additive package
has become depleted. As a guide a 1000 hour oil
change interval would be recommended.
To drain the tank remove the drain plug at the base of
the tank and collect the oil in suitable containers. Oil
may drain faster if the filler cap is loosened.
Waste oil is considered to be a hazardous substance
and as such should be stored and disposed of in
compliance with local legislation.
Whilst the tank is empty the condition of the suction
filter should be checked by removing the filler cap
assembly and visually inspecting it. Should it need to
be replaced it can be removed by reaching down into
the tank and unscrewing it. Screw the new filter into
the tank.
Replace the drain plug and refill the tank.
11.15 Return filter
The return line filter should be changed when the
gauge on top of the filter housing indicates it needs
replacing.
Failure to replace the element at the appropriate time
will result in the filter bypass opening when the back
pressure reaches 1.75 bar. At this point filtration will no
longer be taking place thus exposing all elements of the
10
system to damage. The filter should be replaced when
the indicator on the gauge fitted to the top cover reads
1.4 bar (the top of the green section on the gauge).
To replace the element remove the 3 screws holding
the top cover onto the filter body, there is a spring
underneath the cover holding the filter in place.
Remove the cover and withdraw the filter element. Fit
the new filter element into the filter housing making
sure the “O” ring around the top cover is in place.
Replace the cover and tighten the screws.
11.16 Hose inspection
IMPORTANT.
Due to ageing, wear, damage and for
other reasons, hydraulic hose assemblies represent a
particular hazard. Therefore, the user has to check
hydraulic hose assemblies prior to their first use and at
regular 3 month intervals.
NOTE:
Subject to the conditions of operation, all
hydraulic hoses have a defined lifespan of up to 8
years. It is recommended that the hoses are replaced
within this time to minimise risk of failure.
Visual Inspection Hose/Fitting:
Any of the following
conditions require immediate shut down and
replacement of the Hose Assembly:
Fitting slippage on Hose;
Damaged, cracked, cut or abraded cover (any
reinforcement exposed);
Hard, stiff, heat cracked, or charred Hose;
Cracked, damaged, or badly corroded Fittings;
Leaks at Fitting or in Hose;
Kinked, crushed, flattened or twisted Hose;
Blistered, soft, degraded, or loose cover.
Functional test:
WARNING.
Fluids under pressure can be
dangerous and potentially lethal and, therefore,
extreme caution must be exercised when working with
fluids under pressure and handling the Hoses
transporting the fluids. From time to time, Hose
Assemblies will fail if they are not replaced at proper
time intervals. When Hoses fail, generally the high
pressure fluids inside escape in a stream which may or
may not be visible to the operator. Under no
circumstances should you attempt to locate a leak by
“feeling” with your hands or any other part of the body.
High pressure fluids can and will penetrate the skin and
cause severe tissue damage and possibly loss of limb.
WARNING.
Even seemingly minor hydraulic fluid
injection injuries must be treated immediately by a
doctor with knowledge of the tissue damaging
properties of hydraulic fluid.
Operate the system at maximum operating pressure
and check for possible malfunctions and leaks. Avoid
potential hazardous areas while testing and using the
system.
11.17 Hydraulic valve and electric controls
If problems are experienced with either the hydraulic
system or electric controls, please contact Teagle
Machinery Ltd. for advice.
