Adjust Armature Air Gap

TM 5-4240-501-14P IGNITION FLYWHEEL TYPE—INTERNAL BREAKER NOTE: Always clean breaker points after adjustment. Open the points and insert a piece of lintless paper. Draw the paper through the points. Open points when removing paper so it will not tear, leaving paper between the points. Breaker Point Cover The breaker point cover, Fig. 21, protects the points from dirt. The opening for the primary and/or ground wire should be sealed with No. 2 Permatex" or similar sealer to prevent dirt from entering the breaker box. Cover should not be distorted so as to lose its seal around the outer edge. Replace if damaged. NOTE: Engines used for winter applications use vented breaker covers. See Engine Parts List. Fig. 21 - Breaker Point Cover Install Armature Install governor blade and armature, Fig. 22. The mounting holes in the armature laminations are slotted. Push armature up as far as possible and tighten one mounting screw to hold armature in place. Fig. 22 - Install Armature and Governor Blade Adjust Armature Air Gap Three styles of armatures have been used (Fig. 23, Illus. 1, 2 and 3). Set air gap between the flywheel and armature as shown in Table 1. With armature up as far as possible, and one screw tightened, slip the proper gauge between armature and flywheel. Fig. 24. Turn flywheel - until magnets are directly below the armature. Loosen the one mounting screw and the magnets should pull the armature down firmly against the thickness gauge. Then tighten the mounting screws. Fig. 23 - Armature Style Variations Fig. 24 - Adjusting Armature Air Gap FLYWHEEL KEY Inspect key for partial shearing. If sheared, replace. Check flywheel and crankshaft keyways for damage. If damaged, replace with new parts. Install Flywheel, Nut and/or Starter Clutch Remove all oil or grease, clean flywheel hole and tapered end of crankshaft before assembling flywheel to shaft. Insert zinc key into keyway. Slip spring washer over crankshaft with hollow side toward flywheel. To tighten flywheel nut or starter clutch, reverse removal operation. See "Remove Flywheel Nut or Starter Clutch." Torque to specifications listed in Table No. 1. 2 7