Overhaul

Oil Pump

DISASSEMBLY
Remove the screw which secures oil pump cover and then disassemble oil pump. Inscribe alignment marks on the inner and outer rotors so that they can be replaced in their original positions during reassembly.

NOTE:
Before disassembling the oil pump, remove the relief valve.





ASSEMBLY
1) Using the ST, install the front oil seal.
ST 499587100 OIL SEAL INSTALLER

NOTE:
Use a new front oil seal.





2) Apply a coat of engine oil to inner and outer rotors.
3) Install the inner and outer rotors.
4) Assemble the oil relief valve and install relief valve spring and plug.

NOTE:
Use a new gasket.

5) Install the oil pump cover.





INSPECTION

TIP CLEARANCE
Measure the tip clearance of rotors. If the clearance is out of standard, replace the rotors as a set.





CASE CLEARANCE
Measure the clearance between outer rotor and oil pump case. If clearance is out of standard, replace the oil pump case.





SIDE CLEARANCE
Measure the gap between the inner rotor and the oil pump case to measure the clearance between the inner rotor and the oil pump cover as shown in the figure. If clearance is out of standard, replace the rotor or the oil pump case.





OIL RELIEF VALVE
Check the valve for assembly condition and damage, and the relief valve spring for damage and deterioration. Replace the parts if defective.
Relief valve spring:
Free length
73.7 mm (2.902 in)
Installed length
54.7 mm (2.154 in)
Load when installed
93.1 N (9.49 kgf, 20.93 1bf)

OIL PUMP CASE
Check for worn shaft hole, clogged oil passage, worn rotor chamber, cracks and other faults.

FRONT OIL SEAL
Check the front oil seal lips for deformation and hardening, wear.