Coolant Pump Clean • Old gasket from the gasket surface. NOTICE: Do not immerse the pump in solvent. The solvent may enter the pump's permanently lubricated bearings and cause premature bearing failure. Inspect • Coolant pump shaft for rotation and end play. The shaft and fan hub should turn straight and smoothly. If the hub wobbles or the shaft is noisy or feels “lumpy” when turned, replace the coolant pump. If the shaft end play exceeds 0.381 mm (0.015 in.), replace the coolant pump. • Coolant pump body at the drain (weep) hole. Slight staining around the weep hole is normal.
Only replace the pump if coolant is dripping from the weep hole while the engine is running or while the system is pressurized. Oil Pan and Valve Rocker Covers Figure 12-45 Clean • Parts in solvent. Remove all sludge and varnish. • Old gaskets from the gasket surfaces. Inspect • Gasket flanges for bending or damage. • Rubber grommets and parts on the valve rocker cover for deterioration. • Oil pan for rock damage or cracks. • Oil pan baffle for lack of fit. • Drain plug threads for stripping. Oil Pump Figures 12-46 and 12-47 Remove or Disconnect 1. Driveshaft and retainer. IMPORTANT: Do not remove pickup pipe and screen unless replacement is required.
The pickup pipe has a press fit in to the pump cover. Do not remove the screen from the pipe. The pickup screen and pipe are serviced as a complete assembly only. 2 . Oil pump screen pickup. 3 . Screws. 4 . Pump cover. IMPORTANT: Mark where the idler gear, drive gear and shaft mesh together so they can be reinstalled with the same gear teeth indexed. 5 . Idler gear, drive gear and shaft. 6 . Retaining pin. 7 . Pressure regulator spring. 8 . Pressure regulator valve. Figure 12-45 Inspecting Oil Pan and Components G643 (E) Service Manual Chapter 3. Engine Mechanical System 83