Doosan 7/20, Operation And Maintenance Manual

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MAINTENANCE 29
7/20, P65
VENTILATION
Always check that the air inlets and outlets are clear of debris etc.
COOLING FAN DRIVE
Periodically check that the fan mounting bolts in the fan hub have not
loosened. If, for any reason, it becomes necessary to remove the fan
or re-tighten the fan mounting bolts, apply a good grade of
commercially available thread locking compound to the bolt threads
and tighten to the torque value shown in the
TORQUE SETTING
TABLE later in this section.
The fan belt(s) should be checked regularly for wear and correct
tensioning.
FUEL SYSTEM
The fuel tank should be filled daily or every eight hours. To minimise
condensation in the fuel tank(s), it is advisable to top up after the
machine is shut down or at the end of each working day. At six month
intervals drain any sediment or condensate that may have
accumulated in the tank(s).
FUEL FILTER WATER SEPARATOR
If the fuel filter water separator contains a filter element, it should be
replaced at regular intervals (see the
MAINTENANCE SHEDULE ).
Cleaning the fuel filter pot
Every 100 hours of operation, clean the fuel filter in a clean place to
prevent dust intrusion.
1. Close the fuel filter lever.
2. Remove the top cap, and rinse the inside with diesel fuel.
3. Take out the element, and rinse it with diesel fuel.
4. After cleaning, reinstall the fuel filter, keeping out of dust and dirt.
5. Air-bleed the injection pump.
Fuel filter cartrtidge replacement
1. Apply fuel oil thinly over the gasket and tighten the cartridge into
position by hand-tightening only.
2. Finally, vent the air.
HOSES
All components of the engine cooling air intake system should be
checked periodically to keep the engine at peak efficiency.
At the recommended intervals, (see the MAINTENANCE SHEDULE ),
inspect all of the intake lines to the air filter, and all flexible hoses used
for air lines, oil lines and fuel lines.
Periodically inspect all pipework for cracks, leaks, etc. and replace
immediately if damaged.
ELECTRICAL SYSTEM
Inspect the safety shutdown system switches and the instrument panel
relay contacts for evidence of arcing and pitting. Clean where
necessary.
Check the mechanical action of the components.
Check the security of electrical terminals on the switches and relays i.e.
nuts or screws loose, which may cause local hot spot oxidation.
Inspect the components and wiring for signs of overheating i.e.
discolouration, charring of cables, deformation of parts, acrid smells
and blistered paint.
BATTERY
Keep the battery terminals and cable clamps clean and lightly coated
with petroleum jelly to prevent corrosion.
CAUTION: NEVER clean by blowing air inwards.
1. Fuel filter lever
2. Fuel filter pot
A. “OFF”
B. “ON”
1. O ring
2. Filter element
3. Spring
4. Filter bowl
5. Screw ring
WARNING: Always disconnect the battery cables before
performing any maintenance or service.