Operation and maintenance manual

Section 260-0130
Operators Compartment - Air Conditioning
SM 1405 Rev 2 11-04
8
7. A belt that has operated while rolled over in the
sheave groove may be damaged - replace it.
8. Store belts in a cool, dry place. If stored on a
machine, relieve all belt tension by loosening the
'V' belt tightener.
9. Never attempt to check or adjust belts while they
are running.
Refrigerant Oil
WARNINGS
To prevent personal injury always wear rubber
gloves when handling refrigerant oils.
Too much refrigerant oil will dampen the
cooling effect and too little refrigerant oil may
lead to compressor failure. If in doubt flush
the system.
Oil is required to lubricate the compressor. The oil
mixes with the refrigerant and is carried around the
system. The compressor is supplied with an oil
charge. However, additional oil is required, the
amount depending on the length of refrigerant hose
being used. The quantity added should be calculated
using the following equation:
Amount of oil to add in fl oz. =
(0.47 x total length of hoses in m) - 2.15
If any component is replaced the following amount of
oil should be added to the system;
Condenser add 1 fl oz (28.4 ml)
Drier add 1 fl oz (28.4 ml)
Evaporator add 3 fl oz (85.2 ml)
Compressor add 4.4 fl oz (125 ml)
The oil should be added to the oil filling port of the
compressor before the evacuation procedure is
started or by using an oil injector when the system is
being charged, observing the following good
practises:
a. Only pour the amount required from the container
straight into a CLEAN measuring jug and
immediately pour the oil into the compressor.
b. Re-cap container tightly as soon as the required
amount has been taken (never leave an oil container
open).
c. Do not mix different oils.
4. Ensure all hoses and hose clamps are free from
contact with sharp metal, moving parts or near to
manifolds.
5. Inspect condensation drain lines for debris, sharp
bends or breaks.
6. Inspect the clutch wire from the thermostat for bare
spots.
7. Inspect bolts and nuts on the compressor and
mounting bracket for proper tightness.
8. Inspect and clean outside and inside cab air filters
periodically, depending on dust conditions. Replace the
outside filter when it becomes saturated to the point it
won't come clean.
Maintenance of 'V' belt Drives
1. Listen for 'ticking' sound - they mean interference
with the belts. Visually inspect for bent or damaged
belt guards.
2. Replace all belts in a mismatched set at one time to
ensure even load distribution.
3. Periodically check tension and keep belts tight.
- The ideal tension is the lowest tension at which the
belt will not slip under peak load conditions.
- Check belt tension frequently during the first 24 - 48
hours of run-in operation.
- Initial belt tension should be 445 N (100 lbf)
dropping to 334 N (75 lbf) after the first 48 hours.
- There should be a freeplay of 10 mm in the 'V' belt.
- Do not over tension belts.
- Keep belts free from foreign material that may
cause slippage.
- Inspect the V-drive periodically. Re-tension belts if
they are slipping.
- Maintain sheave alignment with a strong straight
edge tool while tensioning belts.
4. Never attempt to correct belt slippage by using a
belt dressing. The dressing may cause softening and
deterioration.
5. If belt slips, even when properly tensioned, check
for overload, worn sheave grooves or oil or grease on
the belts.
6. Never pry a 'V' belt or force it into the sheave
groove. Loosen the 'V' belt tightener prior to
installation.