INSPECTION OF OIL PUMP 1. INSPECT RELIEF VALVE Coat the valve with engine oil and check that it falls smoothly into the valve hole by its own weight. If it does not, replace the relief valve. If necessary, replace the oil pump assembly. 2. INSPECT BODY CLEARANCE Using a thickness gauge, measure the clearance between the driven gear and body. Standard clearance: 0.03 — 0.15 mm (0.0041 — 0.0069 in.) Maximum clearance: 0.2 mm (0.008 in.) If the clearance is greater than maximum, replace the drive gear and/or body. 3. INSPECT GEAR BACKLASH Using a thickness gauge, measure the backlash as shown. Standard backlash: 0.5 — 0.6 mm (0.020 — 0.024 in.) Maximum backlash: 0.9 mm (0.035 in.) If the backlash is greater than maximum, replace the drive shaft and/or driven gear. 4. INSPECT SIDE CLEARANCE Using a thickness gauge and flat block, measure the side clearance as shown. Standard clearance: 0.03 — 0.09 mm (0.0012 — 0.0035 in.) Maximum clearance: 0.15 mm (0.0059 in.) If the clearance is greater than maximum, replace the drive shaft and driven gear and/or body.