Nissan Maxima Service and Repair Manual: Oil pump
Removal and Installation
- Remove the engine from the vehicle. Refer to EM-103, "Removal and Installation".
- Remove the upper oil pan. Refer to EM-37, "Removal and Installation (Upper Oil Pan)".
- Remove the timing chain. Refer to EM-64, "Removal and Installation".
- Remove oil pump assembly.
Installation is in the reverse order of removal.
Disassembly and Assembly
- Oil pump housing
- Outer rotor
- Inner rotor
- Oil pump cover
- Regulator valve set
- Regulator valve
- Regulator plug
- Oil strainer
CAUTION: Before assembly, apply new engine oil to the parts as shown.
- Remove the oil pump cover.
- Remove inner rotor and outer rotor from oil pump housing. CAUTION: The outer rotor has directional vanes in relation to the rotation of the oil pump shaft. Note the outer rotor vane direction for assembly.
- Remove oil strainer from oil pump housing.
- After removing regulator plug, remove spring and regulator valve.
INSPECTION AFTER DISASSEMBLY
Clearance of Oil Pump Parts
- Measure clearance with feeler gauge.
- Clearance between outer rotor and oil pump body (position 1).
- Tip clearance between inner rotor and outer rotor (position 2).
- Measure clearance with feeler gauge and straightedge.
- Side clearance between inner rotor and oil pump body (position 3).
- Side clearance between outer rotor and oil pump body (position 4).
- Calculate the clearance between inner rotor and oil pump body as follows:
- Measure the outer diameter of protruded portion of inner rotor (position A).
- Measure the inner diameter of oil pump body with inside
micrometer (position B).
(clearance 5) = (inner diameter of oil pump body B) - (outer diameter of inner rotor A)
- If out of specifications, replace oil pump assembly.
- Visually inspect components for wear and damage.
- Check oil pressure regulator valve sliding surface and valve spring.
- Coat regulator valve with engine oil. Check that it falls smoothly
into the valve hole by its own weight.
If damaged, replace oil pump assembly.
Regulator Valve Clearance
(Clearance 6) = D (Valve hole diameter) - E (Outer diameter of valve)
If it exceeds the standard, replace the oil pump assembly.
- Coat regulator valve with engine oil.
- Check that it falls smoothly into the valve hole by its own weight.
Assembly is in the reverse order of disassembly.
- Assemble the outer rotor in the correct vane orientation to rotation as noted during disassembly and the inner rotor with the groove on the oil pump cover side.
- Do not reuse O-ring.
- Before assembly apply new engine oil to the parts as specified.