Engine Cooling System: Removal & Installation Nissan Altima L31

Removal

1. Drain coolant. Refer to «CHANGING ENGINE COOLANT»(ref-183495-S22544398862005081400000) .
2. Remove air duct with air cleaner assembly.
3. Disconnect radiator upper hose, lower hoses and mounting bracket.
4. Disconnect the A/T oil cooler hoses, if equipped. Plug the hoses to prevent A/T oil loss.
5. Remove radiator and radiator fan assembly.

Installation

1. Installation is in the reverse order of removal.

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1. Attach the spacer to the tip of the radiator plate pliers A. Spacer specification: 1.5 mm (0.059 in) thick x 18 mm (0.71 in ) wide x 8.5 mm (0.335 in) long.
2. Make sure that when radiator plate pliers A are closed dimension H is approx. 7.6 mm (0.299 in).
3. Adjust dimension H with the spacer, if necessary.

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1. Remove tank with Tool. Grip the crimped edge and bend it upwards so that Tool slips off. Do not bend excessively. In areas where Tool cannot be used, use a screwdriver to bend the edge up. Be careful not to damage tank.
2. Make sure the edge stands straight up.
3. Remove oil cooler from tank (A/T model only).

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1. Install oil cooler into the tank (A/T model only). Pay attention to direction of conical washer.
2. Clean contact portion of tank.
3. Install sealing rubber gasket. Push it into the tank groove with your fingers. Be careful not to twist sealing rubber gasket.
4. Caulk tank in specified sequence with Tool. Use pliers in the locations where Tool cannot be used.
5. Make sure that the rim is completely crimped down. Standard height H: 8.0 - 8.4 mm (0.315 - 0.331 in)
6. Confirm that there is no leakage. Refer to «INSPECTION»(ref-183495-S01367026812005081400000) .

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1. Apply pressure with Tool. Specified pressure value: 157 kPa (1.57 bar, 1.6 kg/cm 2 ,23 psi) WARNING: To prevent the risk of the hose coming undone while under pressure, securely fasten it down with a hose clamp. Attach a hose to the oil cooler as well (A/T model only).
2. Check for leakage.

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1. Drain coolant. Refer to «CHANGING ENGINE COOLANT»(ref-183495-S22544398862005081400000) . CAUTION: Perform when the engine is cold.
2. Remove the following parts: Under cover, using power tools. Alternator, water pump and air compressor drive belt.
3. Remove the water pump. NOTE: If necessary, the alternator and exhaust manifold catalytic convertor assembly must be removed to remove the water pipe. CAUTION: Handle the water pump vane so that it does not contact any other parts. Water pump cannot be disassembled and should be replaced as an assembly.

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1. Visually check that there is no significant dirt or rusting on the water pump body and vane.
2. Check that there is no looseness in the vane shaft, and that it turns smoothly when rotated by hand.
3. If the water pump does not perform properly, replace the water pump assembly.

1. Installation is in the reverse order of removal.

1. Drain engine coolant. Refer to «CHANGING ENGINE COOLANT»(ref-183495-S22544398862005081400000) .
2. Remove radiator lower hose from the engine coolant inlet side.
3. Remove engine coolant inlet and thermostat.

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1. Place a thread so that it is caught in the valves of the thermostat. Immerse fully in a container filled with water. Heat while stirring.
2. The valve opening temperature is the temperature at which the valve opens and the falls from the thread.
3. Continue heating. Check the full-open lift amount. NOTE: The full-open lift amount standard temperature for the thermostat is the reference value.
4. After checking the full-open lift amount, lower the water temperature and check the valve closing temperature.

Installation is in the reverse order of removal.

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1. Install the thermostat with the whole circumference of the flange part fitting securely inside the rubber ring.
2. Install the thermostat with the jiggle valve facing upwards. The position deviation may be within the range of +/-10°.
3. If necessary, to install the heater pipe, first apply a mild detergent to the O-ring and then quickly insert the pipe into the housing.

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1. Drain the engine coolant. Refer to «CHANGING ENGINE COOLANT»(ref-183495-S22544398862005081400000) .
2. Remove the upper radiator hose, heater pipe, throttle body inlet hose, and heater hose.
3. Remove the engine coolant outlet.
4. Remove the engine coolant control valve.

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1. Place a thread so that it is caught in the valve of the water control valve. Immerse fully in a container filled with water. Heat while stirring.
2. The valve opening temperature is the temperature at which the valve opens and the falls from the thread.
3. Continue heating. Check the full-open lift amount. NOTE: The full-open lift amount standard temperature for the water control valve is the reference value.
4. After checking the full-open lift amount, lower the water temperature and check the valve closing temperature.

Standard values

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Installation is in the reverse order of removal.

1. Install the water control valve with the whole circumference of the flange part fitting securely inside the rubber ring.
2. Install the water control valve with the up-mark facing up and the frame center part facing upwards. The position deviation may be within the range of +/-10°.

1. Remove the undercover using power tool.
2. Drain the coolant from the radiator. Refer to «Changing Engine Coolant»(ref-183495-S21164635392005081400000) .
3. Disconnect radiator upper and lower hoses.
4. Remove the upper and lower radiator shroud.
5. Remove the A/T oil cooler hoses (if equipped).
6. Disconnect the reservoir tank hose.
7. Remove the radiator mounting brackets.
8. Remove the radiator.

Installation is in the reverse order of removal.

1. Fill the radiator with coolant. Refer to «Changing Engine Coolant»(ref-183495-S21164635392005081400000) .

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1. 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 radiator cap negative-pressure valve. Check that there are no abnormalities in the opening and closing conditions of the negative-pressure valve.
2. Check radiator cap relief pressure. Standard: 78 - 98 kPa (0.8 - 1.0 kg/cm 2 , 11 - 14 psi) Limit: 59 - 98 kPa (0.6 - 1.0 kg/cm 2 , 9 - 14 psi) When connecting the radiator cap to the tester, apply water or coolant to the cap seal surface. Replace the radiator cap if there is an abnormality in the negative-pressure valve, or if the open-valve pressure is outside of the standard values.