Starter Motor Noise
To correct starter motor noise during starting, see Fig 1. If the complaint is noise, correction can be achieved by proper shimming as follows:
- Check for a bent or a worn flywheel. Start the engine and carefully touch the outside diameter of the rotating flywheel ring gear with chalk or a crayon to show the high point of the tooth runout. Turn the engine OFF and rotate the flywheel so that the marked teeth are in the area of the starter pinion gear.
- Disconnect the negative battery cable to prevent cranking the engine. Check the pinion to flywheel clearance by using a wire gauge of .02"(.5 mm) minimum thickness (or diameter). Center a pinion tooth between two flywheel teeth and the gauge. Do not gauge in the corners, where a misleading larger dimension may be observed. If the clearance is under this minimum, shimming the starter away from the flywheel is required.
- If the clearance approaches .06" (1.5 mm or more), shimming the starter toward the flywheel is required. This condition is generally the cause of broken flywheel teeth or the starter housing. Shim the starter toward the flywheel by shimming only the outboard starter mounting pad. A shim of .016" (.40 mm) thickness at this location will decrease the clearance by approximately .012" (.30 mm). If normal starter shims are not available, plain washers or other suitable material may be used as shims.