29. Handling Air Conditioner (for Cabin)

5)Adjust the air direction with the air outlet grille.

•Set the fan switch for ventilation to apply preload to the inside of the cabin when the air conditioner is not used, so that no dust can come into the cabin easily during operation.

Important

Be sure to turn the air conditioner ON after starting the engine to prevent excessive force to the compressor etc.

29-2-2.Heating

1)Set the fan switch at any of the three positions (Low, Medium or High).

2)Set the temperature control lever at the WARM position (the left position).

3)Turn the air conditioner switch OFF. (The lamp goes off.)

29-2-3.Heating for dehumidification

(In the case that the window glass tends to get fogged in rainy weather in spring or autumn.)

With the heating turned on, turn the air conditioner switch ON (the lamp goes on).

•If the temperature inside the cabin is low, dehumidification might not work because the compressor does not operate even if the air conditioner switch is turned ON.

29-2-4.Stop

1)Turn the air conditioner switch OFF. (The lamp goes off.)

2)Turn the fan switch OFF.

•The air conditioner also stops only by turning the fan switch OFF.

Temperature control lever

Fan switch

Air conditioner switch ON (The lamp goes on.)

29-3. Maintenance, inspection and servicing of air conditioner

Daily maintenance and periodic inspection and servicing are required for the air conditioner to use it comfortably in the best condition.

Proper maintenance allows reduction in trouble and longer life of the air conditioner.

Exact inspection and servicing prevent trouble and reduce the cost for repair.

It is recommended that the rubber hoses and electrical wires should be replaced every two years to use the air conditioner in the best condition.

List of inspection items for air conditioner

PartCheck itemServicing

Daily inspection

CondenserCheck the cover and the fin for contamination and clogging.Clean Compressor driving beltCheck the belt for tension and damage.Repair or replace Sight glassCheck the refrigerant quantity.

29-3-1.Checking and cleaning condenser

•Be sure to stop the engine and remove the starter key before checking and servicing the condenser.

•Be sure to reinstall the cover and other parts, which have been removed for checking and servicing, to their original positions after completion of the work.

Check the condenser cover, if there is any mud or dirt on the cover, then remove the cover to wash it off with water.

•If there is some mud or dirt on the fin, it causes the degradation of the air conditioner performance. Wash it off from the fin with water by using a soft brush.

•If the fin is crushed or deformed, it also causes the deterioration of the air conditioner performance. Repair it with a screwdriver or the like while taking care not to damage the fin.

29-3-2.Checking and servicing compressor driving belt

Stop the engine and remove the starter key before checking and adjusting the compressor driving belt.

Press the middle of the condenser driving belt to check the slack of the condenser driving belt.

Driving belt

Pressing load : Approx. 22 lbs. (98.1 N)

Adequate slack : 0.3 to 0.35 in. (8 to 9 mm)

If the slack of the belt is inadequate, adjust it according to the following procedure :

1)Remove the cover to press the middle of the belt with a load of approximately 22 lbs. (98.1 N). Adjust the belt tension by tightening the tension pulley bolt and lock nut, tighten the adjust nut so that the slack of the belt should be adequate.

•If the belt tension cannot be adjusted to the specified slack since the belt has lost its elasticity, replace the belt with a new one.

2)Tighten the tension pulley bolt.

3)Check if each pulley or the belt is damaged especially if the belt has contact with the bottom of the pulley groove.

•If there are any cuts on the belt or cracks in it, replace it with a new one.

Compressor driving belt : Mitsuboshi : MPMF-6370 or its equivalent

Adequate slack 0.3 to 0.35 in. (8 to 9 mm)

Pressing load 22 lbs. (98.1 N)

Lock nut adjust nut Bolt

Tension pulley

016150-00E

29-3-3.Checking refrigerant quantity

Open the engine hood B to see the flow of the refrigerant air foam from the sight glass (inspection window) of the liquid tank according to the following procedure to check the refrigerant quantity.

1)Start the engine and run it at the maximum speed.

2)Set the fan switch at "High".

3)Set the temperature control lever at "COOL" (the right position).

4)Turn the air conditioner switch ON. (The lamp goes on.)

5)Check the refrigerant condition from the sight glass and compare it with the check list shown below.

Important

If the refrigerant quantity is not normal, ask your dealer for check and repair.

Check list for refrigerant quantity

Temperature of high and low pressure pipes

Temperature difference is big.

High pressure pipe : hot

Low pressure pipe : cold

Compressor discharge side temp. : 158°F (70°C)

Compressor intake side temp. : 41°F (5°C)

Sight glassAlmost transparent. Even if air foam flow is seen, it becomes transparent as the engine speed changes.

High pressure pipe is warm and low pressure pipe is rather cold. Temperature difference is not so big.

Air foam flow can always be seen. It is sometimes transparent or white.

There is almost no difference in temperature between high and low pressure pipes.

Flow of mist or the like can be seen slightly.

High pressure pipe is hot and low pressure pipe is rather warm. There is some difference in temperature between them.

No air foam flow can be seen by fully opening cabin windows, idling engine, and rotating fan to the maximum.

Pipe jointsNormalSome parts are contaminated by oil.

Refrigerant quantity The quantity is adequate and normal.

Refrigerant might leak in a small amount from some part.

Some parts are badly contaminated by oil.

Almost all refrigerant leaks and does not remain.

Refrigerant is too much.

*1 :When the outside air temperature is low, air foam might be seen even if the refrigerant quantity is adequate.

*2 :No air foam can be seen either when there is no refrigerant. Therefore, be sure to check the difference in temperature between the high and low pressure pipes.