7.SEPARATION OF THE REAR TRANSMISSION AND CYLINDER CASE

Parts which can be inspected during This operation

- Control valve

- Control linkage

- Piston and lift crank linkage

- PTO change gears.

Inspection and service of the rear transmission should be performed following the instructions in the paragraph : 5 SEPARATION OF THE REAR TRANSMISSION AND SPACER TRANSMISSION

1)Removal

(1) Remove the operator’s seat.

(10) Detach the delivery pipe from the cylinder case.

(12) Remove the slow-return check valve along with the shaft.

(13) Remove the 3-point lift link and related parts from the lift arm.

(14) Remove the Cylinder case tightening bolts.

(15) Detach the cylinder case assembly from the rear transmission

FIG.2-59 cylinder case

2) Installation

Reassemble the reverse order of disassemble.

(1) Tighten the cylinder case on the rear transmission case to the specified torque.

FIG.2-58 operator’s seat

(2) Remove the position lever

(3) Remove the lever guide(RH)

(4) When the tractor is equipped with an optional remote control valve,remove the remote control lever and related parts from the bracket.

(5) Remove the back panel

(6) Remove the tank cover

(7) Remove the wiring for the rear combination lamps and trailer socket coupler.

(8) Drain the fuel of fuel tank.

(9) Remove the fuel tank and tank stay bracket

Tightening torque

5.4~6.87 Kgf.m (39.8~50.6lb.fts)

(2) After reassembly, make sure that the system functions properly.

SECTION 1. RADIATOR

1.General description

The pressure cooling system includes mainly the radiator,water pump,multi-blade fan, and the thermostat.During the warm-up period,the thermostat remains closed and coolant is directed through by-pass to the suction side of the water pump

Coolant then circulates through the cylinder block and water pump only to provide a uniform and fast warm-up period. Once the engine has reached operating temperature,the thermostat opens and coolant is pumped from the bottom of the radiator via the lower hose into the cylinder block. Here it circulates through the block and around the cylinders.

From the cylinder block,coolant is directed through the cylinder head and into the thermostat housing.With the thermostat open,coolant passes through the housing and upper radiator hose into the top of the radiator where it is circulated to dissipate heat.

2. Radiator

The radiator consists of radiator cores, a tank to Flow coolant,side plates to install the radiator, and a fan guide.

Fin-tube type cores are used and the cores and tank is made of anti corrosive copper and Copper alloy.

4. REMOVAL OF THE RADIATOR

1) Release the clamp and remove the upper hose.

2) Release the clamp and remove the lower hose.

3) Release the hose clamp and remove the water drain hose.

Note:

- Refer to the paragraph”SEPARATION OF THE ENGINE AND THE FRONT AXLE BRACKET in chapter 2 for operation up to this step.

-When removing the radiator,take care not to damage the radiator cores and oil cooler.

5. INSPECTION OF EACH PART

(1) Inspection for radiator water leaks.

Water leaks are liable to occur at the fitting portion between the upper tank and the core section or between the lower tank and the core section.

If any water leak should occur there,repair the leak by soldering.Besides making a visual check,a more complete inspection should be accomplished as follows:

a. Leak test with compressed air.

Place the radiator as shown in the figure. Close the openings for water inlet and with something like a rubber plug and apply compressed air (1 f/㎠ or 14.2psi) through the drain pipe into the radiator.

Excessively compressed air may damage the cores, so perform the air delivery carefully,watching the pressure gauge. Water leaks are inspected by watching for rising air bubbles.

b.Leak test with a radiator cap tester

With the inlet and outlet pipes plugged up and the radiator filled with water,replace radiator cap with a radiator cap tester as shown in the figure. Pump up the pressure in the radiator to the specified value and check to see if there are any leaks in the radiator.

When the radiator is water-tight,the pressure indicated on the pressure gauge does not increase,but if there are leaks,the pressure decreases.This tester is also applicable for leak tests for the whole cooling system,not only for the radiator.The test method is the same as mentioned above.

Testing Pressure

1.8Kgf/

2) Inspection for radiator clogging

To inspect the radiator cores to see if they are clogged with fur or rust,remove the radiator cap and check for transparency of the coolant,and for rust or fur formation around the radiator throat inside the radiator.

If some rust or fur has formed or the coolant transparency is very poor,the radiator should be cleaned.

a. Cleaning the radiator inside.

-Place the radiator upside down and supply pressurized water from a faucet to the lower tank, draining through the upper tank,as shown in the figure to wash out accumulated deposits.

-Clean with a detergent

When cleaning the radiator with a detergent, follow the instructions given by its manufacturer. Different detergents have different characteristics.

b. Cleaning the radiator exterior

- Cleaning the net (wire mesh)

After the tractor has been operated in dusty conditions,check the net daily and clean it if necessary.

-Cleaning the radiator cores

Clean the radiator cores by applying water spray or compressed air so as to for a right angle with the radiator cores,moving water application in parallel.

Note:

When cleaning the radiator cores with pressurized water,be sure to apply it at a right angle to the cores. Slanted application might deform their cooling fins.

3) Visual inspection of the exterior parts

When the radiator exterior is corroded,cracked,or badly damaged,replace the radiator.Also replace damaged or fatigued water hoses.

Retighten loose hose clamps securely if water is leaking through the hose clamps securely ,or replace them if necessary.

4) Inspection of the radiator cap.

FIG.3-7

-Function test:

The pressure type radiator cap has a pressure valve and a vacuum as shown in the figure.

Both valves are held against there seats by springs while the pressure in the cooling system remains within a specified range,thus keeping the cooling system air-tight.

When the pressure in the radiator rises higher than the specified valves,it overcomes the force of the pressure valve spring and open the pressure valve to release excess pressure through the overflow pipe as shown in the figure.

6. RADIATOR REASSEMBLY

Reassemble the radiator in the reverse order of disassembly.

Note:

- The rubber hoses should be clamped securely and must not interfere with the cooling fan.

- The radiator cores must not interfere with the cooling fan.

7. DAILY INSPECTION

1) Coolant level inspection and coolant replacement

When the radiator is hot after operation,be sure to wait until the coolant cools down sufficiently before removing the radiator cap. If this is not done,heated vapor might burst out and cause burns.Use fresh water from a faucet as the coolant. When the coolant is replenished or changed,let the engine idle for a while for the coolant to circulate sufficiently in the cooling system and replenish if necessary after stopping the engine.

2)Antifreeze

When The weather is cold,use an antifreeze to prevent the engine from freezing.The freezing point differs according to the mixture ration of water and antifreeze.Therefore,prepare an antifreeze solution which will have a freezing point 5℃ lower than the estimated lowest atmospheric temperature in your environment.

Precaution for filling antifreeze.

When the coolant temperature falls enough to cause the vapor to condense in the cooling system and decrease the coolant volume,the radiator pressure becomes negative.When this occurs,the vacuum valve opens to let outside air into the radiator as shown in the figure, thus preventing the radiator from being deformed.

- The radiator interior should be washed clean ahead of time.

- As concerns of mixing ratio of an antifreeze, follow its manufacture's instructions.

- Antifreeze should be blended well with water before filling.

- When the coolant level is lowered due to evaporation,maintain the level by adding water, not by using an antifreeze solution.

- When the coolant level is lowered due to leaks, maintain the level by adding an antifreeze solution of the same mixing ratio.

- As antifreeze corrodes point,take care not to spill it on painted parts.

-The tractor is filled with a permanent type antifreeze (Mobile Long Life Coolant) when shipping(mixing ratio:50%)

Countermeasures Causes Problems TABLE

1) Overheating

(1) Low coolant level

(2) Fatigued pressure valve spring

(3) Loose or broken fan belt

(1)Replenish coolant and inspect water leaks.

(2)Replace radiator cap.

(3)Adjust belt tension or replace.

(4)Replace. (4) Oily fan belt

(5)Replace. (5) Poor thermostat

(6) Poor water pump or water leaks

(7) Clogged water passages

(8) Improper injection timing

(9) Clogged air ways

(10) Fuel gas enters water jacket due to broken cylinder gasket

(6)Repair or replace.

(7)Clean radiator and water passages.

(8) Adjust injection timing.

(9) Clean radiator exterior.

(10) Inspect cylinder head and replace cylinder gasket

2) Overcooling

(1)Replace (1) Poor thermostat

(2) Excessive low atmospheric temperature

(2) Decrease radiator working area by radiator masking.

3)Lose of coolant

(1)Repair or replace (1) Leaking radiator

(2) Loosely clamped or broken water hose

(3) Fatigued pressure valve spring

(4) Leaking water pump

(5) Water leakage through cylinder head gasket

(2)Retighten or replace

(3)Replace radiator cap

(4)Repair or replace

(5) Inspect cylinder head and Replace gasket

(6)Replace (6) Cracked cylinder head or body

4) Noisy cooling fan

(1)Replace (1) Poor water pump bearing

(2) Loose or bent fan

(2)Retighten or replace

(3)Replace. (3) Unbalanced fan

(4) Poor fan belt

(4)Replace.