Engine Oil Pump Overhaul

Exploded View
Special Tools Required

Pin driver, 6.0 mm
 07744-0010500
Oil Pump Removal
  1. Turn the crankshaft pulley so its top dead center (TDC) mark (A) lines up with the pointer (B).
  1. To hold the rear balancer shaft, insert a pin driver (A) into the maintenance hole in the balancer shaft holder and through the rear balancer shaft.
  1. Turn the crankshaft counterclockwise to compress the oil pump chain auto-tensioner.
  1. Align the holes on the lock (A) and the oil pump chain auto-tensioner (B), then insert a 3.0 mm (0.1 in.) diameter pin (C) into the holes. Turn the crankshaft clockwise to secure the pin.
  1. Use a transmission jack to lift the transmission 30−40 mm (1.2−1.6 in.), then remove the oil pump chain auto-tensioner.
  1. Loosen the oil pump sprocket mounting bolt.
  1. Remove the oil pump sprocket (A), then remove the oil pump (B).
Oil Pump Inspection
  1. Remove the pump housing.
  1. Align the inner rotor tooth (A) with the mark (B) on the outer rotor, then check the inner-to-outer rotor radial clearance between the inner rotor and the outer rotor. If the inner-to-outer rotor radial clearance exceeds the service limit, replace the oil pump.
    Inner Rotor-to-Outer Rotor Radial Clearance
    Standard (New):
    0.05−0.15 mm
    (0.0020−0.0059 in.)
    Service Limit:
    0.19 mm (0.0075 in.)

  1. Check the pump housing-to-rotor axial clearance between the rotor (A) and the pump housing (B). If the pump housing-to-rotor axial clearance exceeds the service limit, replace the oil pump.
    Pump Housing-to-Rotor Axial Clearance
    Standard (New):
    0.035−0.070 mm
    (0.0014−0.0028 in.)
    Service Limit:
    0.12 mm (0.005 in.)

  1. Check the pump housing-to-outer rotor radial clearance between the outer rotor (A) and the pump housing (B). If the pump housing-to-outer rotor radial clearance exceeds the service limit, replace the oil pump.
    Pump Housing-to-Outer Rotor Radial Clearance
    Standard (New):
    0.150−0.210 mm
    (0.0059−0.0083 in.)
    Service Limit:
    0.23 mm (0.009 in.)

Balancer Shaft Inspection
  1. Seat the balancer shaft by pushing it away from the oil pump sprocket end of the oil pump.
  1. Zero the dial indicator against the end of the balancer shaft, then push the balancer shaft back and forth and read the end play.
    Balancer Shaft End Play
    Standard (New):
    0.063−0.108 mm
    (0.0025−0.0043 in.)
    Service Limit:
    0.14 mm (0.006 in.)

  1. Remove the pump housing.
  1. Remove the upper balancer shaft holder (with bearings) (A) and baffle plates (B), then remove the front balancer shaft (C) and the rear balancer shaft (D).
  1. Measure the inner diameter of the No. 1 bearing for the front balancer shaft hole and the rear balancer shaft hole.
    Bearing Inner Diameter
    Front:
    Standard (New):
    20.000−20.020 mm (0.7874−0.7882 in.)
    Service Limit:
    20.03 mm (0.789 in.)
    Rear:
    Standard (New):
    24.000−24.020 mm (0.9449−0.9457 in.)
    Service Limit:
    24.03 mm (0.946 in.)

Front
Rear
  1. Measure the diameters of the No. 1 journals on the front balancer shaft and the rear balancer shaft.
    Journal Diameter
    Front:
    Standard (New):
    19.938−19.950 mm (0.7850−0.7854 in.)
    Service Limit:
    19.92 mm (0.784 in.)
    Rear:
    Standard (New):
    23.938−23.950 mm (0.9424−0.9429 in.)
    Service Limit:
    23.92 mm (0.942 in.)

  1. Clean both balancer shaft No. 2 journals and the bearing halves with a clean shop towel, then place both balancer shafts into the balancer holder.
  1. Place one strip of plastigage across each No. 2 journal.
  1. Reinstall the bearings and the upper balancer shaft holder, then tighten the bolts.
    NOTE: Do not rotate the balancer shafts during inspection.
    Specified Torque
    8 x 1.25 mm 27 N·m (2.8 kgf·m, 20 lbf·ft)
    6 x 1.0 mm 12 N·m (1.2 kgf·m, 8.8 lbf·ft)

Front
Rear
  1. Remove the upper balancer shaft holder and the bearings again, and measure the widest part with the plastigage. If balancer shaft No. 2 journal oil clearance is out-of-tolerance, install new bearings, and recheck. If it is still out-of-tolerance, replace the balancer shafts.
    No. 2 Journal Oil Clearance
    Standard (New):
    0.060−0.120 mm (0.0024−0.0047 in.)
    Service Limit:
    0.15 mm (0.006 in.)

  1. Align the punch mark on the rear balancer shaft in the center of the two punch marks on the front balancer shaft, then install the balancer shafts on the lower balancer shaft holder.
  1. Apply new engine oil to the threads of the 8 mm bolts (A).
  1. Install the upper balancer shaft holder (B) and baffle plates (C).
  1. Install the pump housing.
Oil Pump Installation
  1. Make sure the No. 1 piston top dead center (TDC) mark (A) lines up with the pointer (B).
  1. Align the dowel pin (A) on the rear balancer shaft with the mark (B) on the oil pump.
  1. To hold the rear balancer shaft, insert a pin driver (A) into the maintenance hole in the balancer shaft holder and through the rear balancer shaft.
  1. Apply new engine oil to the threads of the oil pump mounting bolts (A) and oil pump sprocket mounting bolt (B), then Loosely install the oil pump (C) with a new O-ring (D), then install the oil pump sprocket (E).
  1. Tighten the oil pump mounting bolts and the oil pump sprocket mounting bolt.
  1. Remove the pin driver (F).
  1. Install the oil pump chain auto-tensioner.
    NOTE: If the 3.0 mm (0.1 in.) diameter pin come off the auto-tensioner. Compress the auto-tensioner , then install the auto-tensioner.
  1. Remove the 3.0 mm (0.1 in.) diameter pin (A) from the oil pump chain auto-tensioner.