Testing and  Adjusting Section

6.  Install the cover on the oil pump. Install the oil

pump on the engine. Refer to Disassembly and

Assembly, “Engine Oil Pump -  Install” for the

correct procedure.

i04112218

Excessive Bearing Wear  -

Inspect

When some components of the engine show bearing

wear in a short time, the cause can be a restriction in

an oil passage.

An engine oil pressure indicator may show that there

is enough oil pressure, but a  component is worn

due to a lack of lubrication. In such a case, look at

the passage for the oil supply  to the component.

A restriction in an oil supply passage will not allow

enough lubrication to reach a component. A lack of

lubrication to a component will result in early wear.

g02384821

Illustration 55

Typical example

2.  Remove the outer rotor (1). Clean all of the parts.

Look for cracks in the metal or other damage.

i04112221

Excessive Engine  Oil

Consumption - Inspect

3.  Install the outer rotor. Measure the clearance of

the outer rotor to the body.

Engine Oil Leaks on the Outside of

the Engine

Check for leakage at the seals at each  end of the

crankshaft. Look for leakage at the gasket for  the

engine oil pan and all lubrication system connections.

Look for any engine oil that may  be leaking from

the crankcase breather. This can  be caused by

combustion gas leakage around the pistons. A dirty

crankcase breather will cause high pressure in the

crankcase. A dirty crankcase breather will cause the

gaskets and the seals to leak.

Engine Oil  Leaks into  the

Combustion Area of the Cylinders

Engine oil that is leaking into the combustion area of

the cylinders can be the cause of blue smoke. There

are several possible ways for engine oil to leak into

the combustion area of the cylinders:

g02384824

Illustration 56

Typical example

4.  Measure the end play of the  rotor (2) with a

straight edge and a feeler gauge.

•  Leaks between worn valve guides and valve stems

5.  Clean the top face of the oil pump and the bottom

face of the cover.

•  Worn components or damaged  components

(pistons, piston rings, or dirty return holes for the

engine oil)

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KENR8772

67

Testing and  Adjusting Section

•  Incorrect installation of the compression ring and/or

the intermediate ring

•  Leaks past the seal rings in the turbocharger shaft

•  Overfilling of the crankcase

•  Wrong dipstick or guide tube

Excessive consumption of engine  oil can also

result if engine oil with the wrong viscosity is used.

Engine oil with a thin viscosity can be caused by fuel

leakage into the crankcase or by increased engine

temperature.

i04112222

Increased Engine  Oil

Temperature - Inspect

If the oil temperature  is high, then check for  a

restriction in the oil passages of  the oil cooler. A

restriction in the oil  cooler will not cause low oil

pressure in the engine.

Determine if the oil cooler bypass valve is held in the

open position. This condition will allow the oil to pass

through the valve instead of the oil cooler. The  oil

temperature will increase.

Refer to Operation and Maintenance Manual, “Fluid

Recommendations” for the correct lubricating oil.

This document is printed from SPI². Not for RESALE

68

KENR8772

Testing and  Adjusting Section

Cooling System

5.  Check the sending unit. In some conditions, the

temperature sensor in the engine sends signals to

a sending unit. The sending unit converts these

signals to an electrical impulse which is used by a

mounted gauge. If the sending unit malfunctions,

the gauge can show an incorrect reading. Also if

the electric wire breaks or if the electric wire shorts

out, the gauge can show an incorrect reading.

i04112226

Cooling System - Check

(Overheating)

6.  Check the radiator.

Above normal coolant temperatures can be caused

by many conditions. Use the following procedure

to determine the cause of  above normal coolant

temperatures:

a.  Check the radiator for a restriction to coolant

flow. Check the radiator  for debris, dirt, or

deposits on the inside of  the radiator core.

Debris, dirt, or deposits will restrict the flow of

coolant through the radiator.

b. Check for debris  or damage between the fins

of the radiator core. Debris between the fins

of the radiator core restricts air flow through

the radiator core. Refer to Systems Operation,

Testing and Adjusting, “Cooling  System -

Inspect”.

Personal injury can result from escaping fluid un-

der pressure.

If a pressure indication is shown on the indicator,

push the release valve in order to relieve pressure

before removing any hose from the radiator.

c.  Ensure that the radiator size is adequate for

the application. An undersized radiator does

not have enough area for the effective release

of heat. This may  cause the engine to run

at a temperature that is higher than normal.

The normal temperature is dependent on the

ambient temperature.

1.  Check the coolant level in the cooling system.

Refer to Operation and Maintenance Manual,

“Cooling System Coolant Level - Check”. If the

coolant level is too low, air will get into the cooling

system. Air in the cooling system  will cause a

reduction in coolant flow  and bubbles in the

coolant. Air bubbles will keep coolant away from

the engine parts, which will prevent the transfer of

heat to the coolant. Low coolant level is caused by

leaks or incorrectly filling the radiator.

7.  Check the filler cap. A  pressure drop in the

radiator can cause the boiling point to be lower.

This can cause the cooling system to boil. Refer

to Systems Operation, Testing and  Adjusting,

“Cooling System - Test”.

2.  Check the mixture of antifreeze and water. Refer

to Operation and Maintenance Manual,  “Fluid

Recommendations”. If the coolant  mixture is

incorrect, drain the system. Put the correct mixture

of water, antifreeze, and coolant conditioner in the

cooling system.

8.  Check the fan and/or the fan shroud.

a.  The fan must be large enough  to send air

through most of the area of the radiator core.

Ensure that the size of the fan and the position

of the fan are adequate for the application.

3.  Check for air in the cooling system. Air can enter

the cooling system in different ways. The most

common causes of air  in the cooling system

are not filling the cooling system  correctly and

combustion gas leakage into the cooling system.

Combustion gas can get into the system through

inside cracks, a damaged cylinder  head, or a

damaged cylinder head gasket. Air in the cooling

system causes a reduction in coolant flow  and

bubbles in the coolant. Air bubbles keep coolant

away from the engine parts, which prevents the

transfer of heat to the coolant.

b. The fan  shroud must be the proper size and

the fan shroud must be positioned correctly.

Ensure that the size of the fan shroud and the

position of the fan shroud are adequate for the

application.

9.  If the fan is belt driven, check for loose drive belts.

A loose fan drive belt will cause a reduction in the

air flow across the radiator. Check the fan drive

belt for proper belt tension. Adjust the tension of

the fan drive belt, if necessary. Refer to Systems

Operation, Testing and Adjusting, “Belt Tension

Chart”.

4.  Check the water temperature gauge. A water

temperature gauge which does not work correctly

will not show the  correct temperature. Refer

to Systems Operation, Testing and  Adjusting,

“Cooling System - Inspect”.

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KENR8772

69

Testing and  Adjusting Section

10. Check the cooling system hoses and clamps.

Damaged hoses with leaks can normally be seen.

Hoses that have no visual leaks can soften during

operation. The soft areas of the hose can become

kinked or crushed during operation. These areas

of the hose can cause a restriction in the coolant

flow. Hoses become  soft and/or get cracks

after a period of time. The inside of a hose  can

deteriorate, and the loose particles of the hose

can cause a restriction of the coolant flow. Refer

to Operation and Maintenance Manual, “Hoses

and Clamps - Inspect/Replace”.

14. Check the water temperature regulator. A water

temperature regulator that does not  open, or

a water temperature regulator that only opens

part of the way can cause overheating. Refer to

Systems Operation, Testing and Adjusting, “Water

Temperature Regulator - Test”.

15. Check the water pump. A water pump with a

damaged impeller does not pump enough coolant

for correct engine cooling. Remove  the water

pump and check for damage to the impeller. Refer

to Systems Operation, Testing and  Adjusting,

“Water Pump - Test”.

11. Check for a restriction in the air inlet system.

A restriction of the  air that is coming into the

engine can cause high cylinder temperatures.

High cylinder temperatures cause higher than

normal temperatures in the cooling system. Refer

to Systems Operation, Testing and Adjusting, “Air

Inlet and Exhaust System - Inspect”.

16. Check the air  flow through the  engine

compartment. The air flow through the radiator

comes out of the engine compartment. Ensure

that the filters, air conditioner, and similar items

are not installed in a way that prevents the free

flow of air through the engine compartment.

a.  If the measured restriction is higher than the

maximum permissible restriction, remove the

foreign material from the engine air  cleaner

element or install a new  engine air cleaner

element. Refer to Operation and Maintenance

Manual, “Engine Air  Cleaner Element -

Clean/Replace”.

17. Check the aftercooler. A restriction of air flow

through the air to air aftercooler (if equipped) can

cause overheating. Check for debris or deposits

which would prevent the free flow of air through

the aftercooler.

18. Consider high outside temperatures. When

outside temperatures are too high for the rating

of the cooling system, there is not enough of  a

temperature difference between the outside air

and coolant temperatures.

b. Check for  a restriction in the air inlet system

again.

c.  If the measured restriction is still higher than

the maximum permissible restriction, check the

air inlet piping for a restriction.

19. Consider high altitude operation. The cooling

capacity of the cooling system  goes down as

the engine is operated  at higher altitudes. A

pressurized cooling system that is large enough to

keep the coolant from boiling must be used.

12. Check for a restriction in the exhaust system.

A restriction of the air that is coming out  of the

engine can cause high cylinder temperatures.

a.  Make a visual inspection of the exhaust system.

Check for damage to exhaust piping or for a

damaged muffler. If no damage is found, check

the exhaust system for a restriction. Refer to

Systems Operation, Testing and Adjusting, “Air

Inlet and Exhaust System - Inspect”.

i04112228

Cooling System - Inspect

Cooling systems that are not regularly inspected are

the cause for increased engine temperatures. Make

a visual inspection of the cooling system before any

tests are performed.

b. If the  measured restriction is higher than the

maximum permissible restriction, there is a

restriction in the exhaust system. Repair the

exhaust system, as required.

13. Check the shunt line, if the  shunt system is

used. The shunt line must be submerged in the

expansion tank. A restriction of the  shunt line

from the radiator top tank  to the engine water

pump inlet will cause a reduction in water pump

efficiency. A reduction in water pump efficiency

will result in low coolant flow and overheating.

Personal injury can result from escaping fluid un-

der pressure.

If a pressure indication is shown on the indicator,

push the release valve in order to relieve pressure

before removing any hose from the radiator.

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70

KENR8772

Testing and  Adjusting Section

1.  Check the coolant level in the cooling system.

Refer to Operation and Maintenance  Manual,

“Cooling System Coolant Level - Check”.

2.  Check the quality of the coolant. The  coolant

should have the following properties:

•  Color that is similar to new coolant

•  Odor that is similar to new coolant

•  Free from dirt and debris

If the coolant does not  have these properties,

drain the system and  flush the system. Refill

the cooling system with the correct  mixture of

water, antifreeze, and coolant conditioner. Refer

to Operation and Maintenance Manual,  “Fluid

Recommendations”.

g00921815

Illustration 57

Boiling point of water

Remember that temperature and pressure  work

together. When a diagnosis is made  of a cooling

system problem, temperature and pressure must be

checked. Cooling system pressure will have an effect

on the cooling system temperature. For an example,

refer to Illustration 57. This will show the  effect of

pressure on the boiling point (steam) of water. This

will also show the effect of height above sea level.

3.  Look for leaks in the system.

Note: A small amount of coolant  leakage across

the surface of the water pump seals is normal. This

leakage is required in order to provide lubrication for

this type of seal. A hole is provided in the water pump

housing in order to allow this coolant/seal lubricant

to drain from the pump housing. Intermittent leakage

of small amounts of coolant from this hole is not an

indication of water pump seal failure.

Personal injury can result from hot coolant, steam

and alkali.

4.  Ensure that the air flow through the radiator does

not have a restriction. Look  for bent core fins

between the folded cores of the radiator. Also, look

for debris between the folded cores of the radiator.

At operating  temperature, engine  coolant is  hot

and  under  pressure. The  radiator  and  all  lines

to heaters  or  the engine  contain hot  coolant or

steam. Any contact can cause severe burns.

5.  Inspect the drive belts for the fan.

6.  Check for damage to the fan blades.

Remove filler cap slowly to  relieve pressure only

when engine is  stopped and radiator cap  is cool

enough to touch with your bare hand.

7.  Look for air or combustion gas in  the cooling

system.

Cooling System Conditioner contains alkali. Avoid

contact with skin and eyes.

8.  Inspect the filler cap, and check the surface that

seals the filler cap. This surface must be clean.

The coolant level must be to the correct level in order

to check the coolant system. The engine must  be

cold and the engine must not be running.

i04112229

Cooling System - Test

After the engine is cool, loosen  the pressure cap

in order to relieve the pressure out  of the cooling

system. Then remove the pressure cap.

This engine has a pressure type cooling system. A

pressure type cooling system has two advantages.

The cooling system can be operated in a safe manner

at a temperature higher than the normal boiling point

(steam) of water.

The level of the coolant should  not be more than

13 mm (0.5 inch) from the bottom of the filler pipe. If

the cooling system is equipped with a sight glass,

the coolant should be to the proper level in the sight

glass.

This type of system prevents cavitation in the water

pump. Cavitation is the  forming of low-pressure

bubbles in liquids that are caused by  mechanical

forces. It is difficult to create a pocket of air  in this

type of cooling system.

This document is printed from SPI². Not for , RESALE

KENR8772

71

Testing and  Adjusting Section

Checking the Filler Cap

•  Surface for seal

Table 13

Remove any deposits that are found  on these

items, and remove any material that is found on

these items.

Required Tools

Tool

Part Number

Part Description

Qty

2.  Install the filler cap onto Tooling (A).

A

GE50031

Pressurizing Pump

1

3.  Look at the gauge for the exact pressure  that

opens the filler cap.

One cause for a pressure loss in the cooling system

can be a damaged seal on the radiator filler cap.

4.  Compare the gauge reading with the opening

pressure that is listed on the filler cap.

5.  If the filler cap is damaged, replace the filler cap.

Testing The Radiator And Cooling

System For Leaks

Table 14

Required Tools

Tool

Part Number

Part Description

Qty

A

GE50031

Pressurizing Pump

1

g01096114

Illustration 58

Use the following procedure in order to check the

cooling system for leaks:

Typical schematic of filler cap

(1) Sealing surface of both filler cap and radiator

Personal injury can result from hot coolant, steam

and alkali.

Personal injury can result from hot coolant, steam

and alkali.

At operating  temperature, engine  coolant is  hot

and  under  pressure. The  radiator  and  all  lines

to heaters  or  the engine  contain hot  coolant or

steam. Any contact can cause severe burns.

At operating  temperature, engine  coolant  is hot

and  under  pressure. The  radiator  and  all  lines

to heaters  or  the engine  contain hot  coolant or

steam. Any contact can cause severe burns.

Remove filler cap slowly to  relieve pressure only

when engine is  stopped and radiator cap  is cool

enough to touch with your bare hand.

Remove filler cap slowly to  relieve pressure only

when engine is  stopped and radiator cap  is cool

enough to touch with your bare hand.

Cooling System Conditioner contains alkali. Avoid

contact with skin and eyes.

Cooling System Conditioner contains alkali. Avoid

contact with skin and eyes.

1.  After the engine is cool, loosen the filler cap slowly

and allow pressure out of  the cooling system.

Then remove the filler cap from the radiator.

To check for the amount of pressure that opens the

filler cap, use the following procedure:

1.  After the engine cools, carefully loosen the filler

cap. Slowly release the pressure from the cooling

system. Then, remove the filler cap.

2.  Ensure that the coolant level is above the top of

the radiator core.

3.  Install Tooling (A) onto the radiator.

Carefully inspect the filler  cap. Look for any

damage to the seals and to the sealing surface.

Inspect the following components for any foreign

substances:

4.  Take the pressure reading on the gauge to 20 kPa

(3 psi) more than the pressure on the filler cap.

5.  Check the radiator for leakage on the outside.

•  Filler cap

•  Seal

This document is printed from SPI². Not for RESALE

72

KENR8772

Testing and  Adjusting Section

6.  Check all connection points for leakage, and

check the hoses for leakage.

Coolant temperature can also be read on the display

screens of the Electronic Service Tool.

The cooling system does not have leakage only if the

following conditions exist:.

Remove a plug from water manifold assembly. Install

Tooling (A) in the open port:

•  You do not observe any outside leakage.

•  The reading remains steady after 5 minutes.

A temperature indicator of known accuracy can also

be used to make this check.

Start the engine. Run the engine until the temperature

reaches the desired range according  to the test

thermometer. If necessary, place a cover over part of

the radiator in order to cause a restriction of the air

flow. The reading on the water temperature indicator

should agree with the test thermometer within the

tolerance range of the water temperature indicator.

The inside of the cooling system has leakage only if

the following conditions exist:

•  The reading on the gauge goes down.

•  You do NOT observe any outside leakage.

Make any repairs, as required.

i04204217

Engine Oil Cooler - Inspect

Test For The Water Temperature

Gauge

Table 15

Required Tools

Tool

Part Number

Part Description

Qty

Hot oil  and hot components can  cause personal

injury. Do not allow hot  oil or hot components to

contact the skin.

A

-

Thermometer

1

Personal injury can result from escaping fluid un-

der pressure.

Personal injury can result from air pressure.

Personal injury can result without following prop-

er procedure. When using pressure air, wear a pro-

tective face shield and protective clothing.

If a pressure indication is shown on the indicator,

push the release valve in order to relieve pressure

before removing any hose from the radiator.

Maximum air pressure at the nozzle must be less

than 205 kPa (30 psi) for cleaning purposes.

Making contact with  a running engine can cause

burns from  hot parts and  can cause  injury from

rotating parts.

NOTICE

To prevent engine damage, replace the heat exchang-

er for the engine oil  cooler if an engine bearing fails.

Bearing debris cannot be removed  from the heat ex-

changer.

When working on an engine that is running, avoid

contact with hot parts and rotating parts.

NOTICE

Check the accuracy  of the water temperature

indicator or water temperature sensor if  you find

either of the following conditions:

To prevent engine  damage, do not clean  the engine

oil cooler assembly in solvent. Solvent will be trapped

in the heat exchanger, regulator valve assembly, and

oil thermal valve assembly.

•  The engine runs at a temperature that is too hot,

but a normal temperature is indicated. A loss  of

coolant is found.

Remove the following components from the oil cooler

housing before cleaning with solvent:

•  The engine runs at a normal temperature, but a

hot temperature is indicated. No loss of coolant is

found.

•  Heat exchanger

•  Regulator valve assembly

This document is printed from SPI². Not for RESALE

KENR8772

73

Testing and  Adjusting Section

•  Thermal valve assembly

6.  Apply 172 to 276 kPa (25 to 40 psi) of air pressure

while the assembly is under water.

The oil cooler housing and lube filter adapter  can

be cleaned in solvent and blown  dry with filtered

compressed air.

7.  Inspect heat exchanger and Tooling (A) for leaks. If

Tooling (A) connections leak, tighten connections

and continue looking for leaks. Air bubbles at any

location on the heat exchanger indicate a coolant

passage leak. Replace heat exchanger if leaking.

1.  Clean the disassembled oil cooler housing and

lube adapter in a suitable solvent.

2.  Flush and drain oil cooler housing and lube filter

adapter to remove any residue. Dry components

with filtered compressed air.

Heat Exchanger Oil Passage Leak Test

1.  Install Tooling (A) to the heat exchanger. Tighten

the eight M8 x 20 bolts that secure Tooling (A) to a

torque of 29 N·m (21 lb ft).

3.  Inspect the oil cooler housing for cracks and dents.

Check oil cooler housing for blocked orifices and

damaged threads. Replace housing if required.

2.  Close the coolant port valve.

4.  Remove any debris blocking the filter bypass

valve.

3.  Connect air pressure regulator between the oil

port of Tooling (A) and the air supply.

5.  Remove turbocharger oil supply tube connection.

Refer to Disassembly and  Assembly for the

correct procedure.

4.  Immerse heat exchanger and Tooling (A) in a

large container of clean water.

5.  Open oil port valve and allow air to fill oil side of

heat exchanger.

6.  Inspect wire mesh screen for damage or particle

obstruction. If necessary,  clean or replace

turbocharger oil supply tube connection.

6.  Apply 172 to 276 kPa (25 to 40 psi) of air pressure

while the assembly is under water.

7.  Install turbocharger oil supply tube connection.

Refer to Disassembly and  Assembly for the

correct procedure.

7.  Inspect heat exchanger and Tooling (A) for leaks. If

Tooling (A) connections leak, tighten connections

and continue looking for leaks. Air bubbles at any

location on the heat exchanger indicate  an oil

passage leak. Replace heat exchanger if leaking.

Test Oil Cooler Heat Exchanger for

Leaks

Heat Exchanger Internal Leak Test

Table 16

Required Tools

1.  Install Tooling (A) to the heat exchanger. Tighten

the eight M8 x 20 bolts that secure the Tooling (A)

to a torque of 29 N·m (21 lb ft).

Tool

Part Number

Part Description

Qty

Oil Cooler Pressure

Test Plate

A

27610409

1

2.  Connect air pressure regulator between the oil

port of Tooling (A) and the air supply.

Heat Exchanger Coolant Passage Leak

Test

3.  Open coolant port valve to allow water to fill the

coolant side of the heat exchanger.

1.  Install Tooling (A) to the heat exchanger. Tighten

the eight M8 x 20 bolts that secure Tooling (A) to a

torque of 29 N·m (21 lb ft).

4.  Immerse heat exchanger and Tooling (A) in a

large container of clean water.

5.  Apply 172 to 276 kPa (25 to 40 psi) of air pressure

while the assembly is under water.

2.  Close the oil port valve.

3.  Connect air pressure regulator between  the

coolant port of Tooling (A) and the air supply.

6.  Inspect coolant port valve for air bubbles. Bubbles

coming out of the coolant port indicate an internal

leak between oil and coolant passages. Replace

heat exchanger if leaking.

4.  Immerse heat exchanger and Tooling (A) in a

large container of clean water.

7.  Remove Tooling (A) and drain any water, coolant,

and oil out of heat exchanger.

5.  Open coolant port valve and allow air to fill coolant

side of heat exchanger.

This document is printed from SPI². Not for RESALE