Coolant Leak Caution on 1995-2003 Nissan 3.0L, 3.5L Engines - Engine Builder Magazine
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Coolant Leak Caution on 1995-2003 Nissan 3.0L, 3.5L Engines


CONDITION: A severe coolant leak from the water pump’s weep holes causes the coolant to destroy the pump’s bearing as well as leak into the engine’s oiling system. Catastrophic engine failure can result.

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CAUSE:  This engine’s water pump is buried beneath the timing cover since it is internally driven off the engine’s timing chain. Since the front of the pump has direct contact with the engine’s oiling system, the weep holes have been rerouted.  Leaking coolant is channeled back through the pump and into the engine block.  Therefore, if the water pump seal fails, the noticeable leaks will occur as coolant exits the left side of the engine block just below the thermostat housing.

CORRECTION: Be aware of the potential leak points and do not ignore the signs of a leak. It also is recommended that the water pump be changed whenever servicing the timing chain and/or internal timing components.


Use replacement water pump AIRTEX P/N AW9309.

–Courtesy of ASC Industries

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