Nissan Frontier D40. Manual - part 194

OVERHEATING CAUSE ANALYSIS

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Except cool-
ing system 
parts mal-
function

—

Overload on engine

Abusive driving

High engine rpm under no 
load

Driving in low gear for ex-
tended time

Driving at extremely high 
speed

Powertrain system malfunc-
tion

—

Installed improper size 
wheels and tires

Dragging brakes

Improper ignition timing

Blocked or restricted air 
flow 

Blocked bumper

Mud contamination or paper 
clogging

—

Blocked radiator grille

Installed car brassiere

Mud contamination or paper 
clogging

Blocked radiator

Blocked air flow

Blocked condenser

Installed large fog lamp

Symptom

Check items

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ENGINE COOLANT

ON-VEHICLE MAINTENANCE

ENGINE COOLANT

System Inspection

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WARNING:

• Never remove the radiator/reservoir cap when the engine is hot. Serious burns could occur from

high pressure fluid escaping from the radiator or reservoir.

• Wrap a thick cloth around the cap. Slowly push down and turn it a quarter turn to allow built-up pres-

sure to escape. Carefully remove the cap by pushing down and turning it all the way.

CHECKING COOLING SYSTEM HOSES

Check hoses for the following:
• Improper attachment
• Leaks
• Cracks
• Damage
• Loose connections
• Chafing
• Deterioration

CHECKING RESERVOIR LEVEL

• Check if the engine coolant reservoir tank level is within MIN to

MAX when the engine is cool.

• Adjust engine coolant level as necessary.

CHECKING COOLING SYSTEM FOR LEAKS

WARNING:

Never remove the radiator/reservoir cap when the engine is hot. Serious burns could occur from high
pressure coolant escaping from the radiator or reservoir.
• To check for leakage, apply pressure to the cooling system at the

reservoir filler neck using suitable tool and Tool.

CAUTION:

Higher pressure than specified may cause radiator damage.
NOTE:
In case that engine coolant decreases, replenish cooling system
with engine coolant.

• If any concerns are found, repair or replace damaged parts.

CHECKING RESERVOIR CAP

1.

Inspect the reservoir cap.
• Replace the cap if the metal plunger cannot be seen around the edge of the black rubber gasket.
• Replace the cap if deposits of waxy residue or other foreign material are on the black rubber gasket or

the metal retainer.

NOTE:
Thoroughly wipe out the reservoir filler neck to remove any waxy residue or foreign material.

SMA412B

Tool number

: EG17650301 (J-33984-A)

Testing pressure

: 137 kPa (1.4 kg/cm

2

, 20 psi)

WBIA0568E

ENGINE COOLANT

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2.

Pull the negative-pressure valve to open it and check that it
closes completely when released.
• Check that there is no dirt or damage on the valve seat of the

reservoir cap negative-pressure valve.

• Check that there are no abnormalities in the opening and clos-

ing conditions of the negative-pressure valve.

3.

Check reservoir cap relief pressure using suitable tool and Tool.

NOTE:
• Apply engine coolant to the cap seal surface. 
• Replace the reservoir cap if there is any damage in the nega-

tive-pressure valve, or if the open-valve pressure is outside of
the limit.

CHECKING RADIATOR CAP

Inspect the radiator cap.
NOTE:
Thoroughly wipe out the radiator filler neck to remove any waxy residue or foreign material.
• Replace the cap if the metal plunger cannot be seen around the edge of the black rubber gasket.
• Replace the cap if deposits of waxy residue or other foreign material are on the black rubber gasket or the

metal retainer.

CHECKING RADIATOR

Check radiator for mud or clogging. If necessary, clean radiator as follows.

CAUTION:

• Be careful not to bend or damage the radiator fins.
• When radiator is cleaned without removal, remove all surrounding parts such as cooling fan shroud

and horns. Then tape the harness and electrical connectors to prevent water from entering.

1.

Apply water by hose to the back side of the radiator core, with the hose pointed vertically downward.

2.

Apply water again to all radiator core surfaces once per minute.

3.

Stop washing if any stains no longer flow out from the radiator.

4.

Blow air into the back side of radiator core, with the air hose pointed vertically downward.
• Use compressed air lower than 490 kPa (5 kg/cm

2

, 71 psi) and keep distance more than 30 cm (11.8 in). 

5.

Blow air again into all the radiator core surfaces once per minute until no water sprays out.

6.

Check for leaks.

Changing Engine Coolant

INFOID:0000000005276109

WARNING:

• To avoid being scalded, never change the coolant when the engine is hot.
• Wrap a thick cloth around the cap to carefully remove the cap. First, turn the cap a quarter of a turn

to release any built-up pressure, then push down and turn the cap all the way to remove it.

DRAINING ENGINE COOLANT

1.

Turn ignition switch ON and set temperature control lever all the way to HOT position or the highest tem-
perature position. Wait 10 seconds and turn ignition switch OFF.

2.

Remove the engine front under cover. Refer to 

EXT-13, "Removal and Installation"

.

SMA967B

Tool number

: EG17650301 (J-33984-A)

Standard: 98 – 118 kPa (1.0 – 1.2 kg/cm

2

, 14 – 17 psi)

WBIA0570E

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ENGINE COOLANT

3.

Open the radiator drain plug at the bottom of the radiator, and
remove the reservoir cap. This is the only step required when
partially draining the cooling system (radiator only). 

CAUTION:

Do not allow the coolant to contact the drive belts. 

4.

When draining all of the coolant in the system for engine
removal or repair, it is necessary to drain the cylinder block.
Remove the cylinder block drain plugs (A), (B), (C), (D) and
block heater if equipped, to drain the cylinder block as shown.
NOTE:
For Canada, the (D) cylinder block drain plug as shown, is not a
cylinder block drain plug but a block heater.

5.

Remove the reservoir tank to drain the engine coolant, then clean the reservoir tank before installing it.

6.

Check the drained coolant for contaminants such as rust, corrosion or discoloration.
If the coolant is contaminated, flush the engine cooling system. Follow the "Flushing Cooling System" pro-
cedure.

REFILLING ENGINE COOLANT

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