Engine Cooling System: Overhaul Nissan Maxima A34

DISASSEMBLY

1. Remove fan blade.
2. Remove fan motor from fan shroud.

ASSEMBLY

Assembly is in the reverse order of disassembly.

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1. Drain coolant from radiator. Refer to «DRAINING ENGINE COOLANT»(ref-233644-S13037486022006052600000) . CAUTION: Perform when the engine is cold.
2. Remove right-hand side engine cover.
3. Remove coolant reservoir.
4. Remove IPDM E/R mounting bolts and position aside. Refer to «REMOVAL AND INSTALLATION OF IPDM E/R»(ref-233661-S42132645482006052600000) .
5. Remove right-hand tire and splash shield.
6. Remove drive belts. Refer to «REMOVAL»(ref-233643-S17836745932006052600000) .
7. Remove idler pulley, then power steering and generator adjusting bars.
8. Support engine and remove front engine insulator and bracket. Refer to «REMOVAL AND INSTALLATION»(ref-233643-S15386963742006052600000) .
9. Remove water drain plug on water pump side of cylinder block.
10. Remove chain tensioner cover and water pump cover.
11. Remove the chain tensioner assembly. Pull the lever down and release the plunger stopper tab. Insert the stopper pin into the tensioner body hole to hold the lever and keep the stopper tab released. NOTE: An Allen wrench (2.5 mm (0.098 in) is used for a stopper pin as an example. Insert the plunger into the tensioner body by pressing the timing chain slack guide. Keep the slack guide pressed and hold the plunger in by pushing the stopper pin deeper through the lever and into the tensioner body hole. Make a gap between water pump gear and timing chain, by turning the crankshaft pulley approximately 20° clockwise.
12. Remove chain tensioner. CAUTION: Be careful not to drop bolts inside chain case.
13. Remove the three water pump bolts. Make a maximum gap between water pump gear and timing chain, by turning crankshaft pulley counterclockwise until timing chain loosens on water pump sprocket.
14. Screw M8 bolts [pitch: 1.25 mm (0.49 in) length: approx. 50 mm (1.97 in)] into water pumps upper and lower mounting bolt holes until they reach the timing chain case. Then, alternately tighten each bolt for a half turn, and pull out the water pump. Pull straight out while preventing vane from contacting socket in installation area. Remove water pump without causing sprocket to contact timing chain.
15. Remove M8 bolts and O-rings from water pump.

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1. Check for badly rusted or corroded water pump body assembly.
2. Check for rough operation due to excessive end play.

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1. Install new O-rings to water pump.
2. Apply engine oil and coolant to the O-rings as shown. Locate the O-ring with white paint mark to engine front side.
3. Install the water pump. CAUTION: Do not allow cylinder block to interfere with the O-rings when installing the water pump. Check that timing chain and water pump sprocket are engaged. Insert water pump by tightening bolts alternately and evenly. Water pump bolts 8.5 - 10.7 N.m (0.86 - 1.10 kg-m, 75 - 95 in-lb)
4. Remove dust and foreign material completely from backside of chain tensioner and from installation area of rear timing chain case.
5. Turn the crankshaft pulley approximately 20° clockwise so that the timing chain on the timing chain tensioner side is loose. NOTE: When installing the timing chain tensioner, engine oil should be applied to the oil hole and tensioner.
6. Install the timing chain tensioner. Timing chain tensioner 7.0 - 9.3 N.m (0.71 - 0.95 kg-m, bolts 62 - 82 in-lb)
7. Remove the stopper pin. NOTE: An Allen wrench [(2.5 mm (0.098 in)] is used for a stopper pin as an example.
8. Install chain tensioner and water pump cover. Before installing, remove all traces of sealant from mating surface of water pump cover and chain tensioner cover using a scraper. Also remove traces of sealant from the mating surface of the front cover. Apply a continuous bead of RTV Silicone Sealant or equivalent, to mating surface of chain tensioner cover and water pump cover. Refer to «RECOMMENDED CHEMICAL PRODUCTS AND SEALANTS»(ref-233642-S07555866002006052600000) .
9. Install water drain plug on water pump side of cylinder block. Refer to «CHANGING ENGINE COOLANT»(ref-233644-S16252982522006052600000) .
10. Tighten idler pulley bolts to specification. Idler pulley bolts : 25 - 31 N.m (2.5 - 3.2 kg-m, 18 - 23 ft-lb)
11. Installation of remaining components is in the reverse order of removal. Refill engine coolant. Refer to «REFILLING ENGINE COOLANT»(ref-233644-S13472925892006052600000) . After starting engine, let idle for three minutes, then rev engine up to 3,000 RPM under no load to purge air from the high-pressure chamber of the chain tensioner. The engine may produce a rattling noise. This indicates that air still remains in the chamber and is not a matter of concern.

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1. Drain coolant from radiator. Refer to «DRAINING ENGINE COOLANT»(ref-233644-S13037486022006052600000) . CAUTION: Perform when engine is cool.
2. Remove drive belts. Refer to «REMOVAL»(ref-233643-S17836745932006052600000) .
3. Remove water drain plug on water pump side of the engine.
4. Remove right-hand side engine cover.
5. Remove coolant reservoir.
6. Remove IPDM E/R bolts and position aside. Refer to «Removal and Installation of IPDM E/R»(ref-233661-S42132645482006052600000) .
7. Disconnect lower radiator hose.
8. Disconnect oil cooler line.
9. Remove engine coolant inlet and thermostat assembly. Do not disassemble engine coolant inlet and thermostat assembly. Replace them as a unit, if necessary.

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1. Check valve seating condition at ordinary room temperatures. It should seat tightly.
2. Check valve opening temperature and maximum valve lift. VALVE OPENING TEMPERATURE, CLOSING TEMPERATURE AND MAXIMUM VALVE LIFT STANDARD VALUE Thermostat Standard Values Valve opening temperature 80 - 84°C (176 - 183°F) Valve lift 8.6 mm / 95°C (0.339 in / 203°F) Valve closing temperature 77°C (171°F) or higher