1942 - 1947 Chevrolet Shop Manual



	6-15

	HARMONIC BALANCER The harmonic balancer consists of a small flyweight attached to and driven by the crankshaft through two rubber annular rings mounted over six studs riveted to the hub. When the engine is running, any change in the speed of the crankshaft, which would cause vibration, will be resisted by the action of the balancer. This resistance is produced by a floating action between the rubber annular rings and the six driving studs. The flyweight moves back and forth on the rubber mounted studs in the opposite direction to that of the crankshaft, and thereby dampens out or absorbs crankshaft vibrations. Due to the construction of the balancer the parts are not serviced separately. The 1942 harmonic balancer is interchangeable with 1941 models but not with previous models, due to a difference in length. The harmonic balancer puller, Fig. 28, is made in three parts, a drop forged puller body, a puller screw and a driver head. The driver head is made of tool steel with a drill rod pin which is replaceable.	FLYWHEEL Chevrolet flywheels are made from the very best grade of cast iron, and have a steel ring gear shrunk on the outer diameter, with which the starter drive pinion meshes when starting the engine. The flywheel is accurately balanced to assure smooth engine operation at all speeds, and is properly located on the crankshaft flange by three dowels. Attachment to the crankshaft is by six special large head cap screws locked by lock plates. Fig. 29.


		Fig. 29-Method of Locking Flywheel Bolts After the flywheel has been assembled to the crankshaft, it is necessary that the face and the rim of the flywheel be checked for run-out.
	Fig. 28—Harmonic Balancer Puller and Driver In operation the puller body is attached to the balancer by means of the two cap screws in the puller, which screw into the tapped holes in the balancer. This insures the puller body being held firmly against the balancer and helps to hold the balancer together while it is being removed. Next turn the puller screw into the body until the balancer is removed. This puller provides a steady pull on the balancer allowing its removal without damage. When installing the balancer the puller body is removed, the driver placed in the starting crank jaws and the puller body reassembled to the balancer. Next line up the key in the crankshaft with the keyway in the balancer and drive the balancer in position using the puller screw as a driver. If the puller is assembled in any other than this way serious damage will be done to the balancer.

		Fig. 30-Checklng Flywheel Run- Out