1942 - 1947 Chevrolet Shop Manual



	6-12

	In assembling this part to the cylinder block, first use two gaskets and hold in place with three screws. Then place a new camshaft thrust plate over the camshaft hole in the end plate. Using a steel scale with a perfectly straight edge laid against the thrust plate and over to the gear shoulder on the crankshaft, check to see whether or not these two surfaces are flush. Fig 18. If the scale strikes the shoulder on the crankshaft, add another gasket. If there is space between the scale and the shoulder on the crankshaft, remove one gasket. After determining and installing the proper number of gaskets assemble the screws and bolts, and set the screws with a center punch. Crankshaft and Camshaft Gears (Timing Gears) The gear on the end of the crankshaft, or the crankshaft timing gear, is cut from a solid piece of steel. It is a drive fit on the end of the crankshaft as well as being held in place with a key. To remove this gear without damage to it. a gear puller, such as is shown in Fig. 19. is nec-	This sleeve, shown in Fig. 20, removes the gear, but it so damages the thrust plate that it is very important that every time a gear is removed from the camshaft, a new thrust plate must be used.


		Fig. 20—Removing Camshaft Gear In assembling the gear to the camshaft, the back of the front journal of the camshaft must be firmly supported in an arbor press and the camshaft thrust plate assembled to the camshaft, after which the gear is pressed on the shaft far enough so the thrust plate has practically no clearance, yet is free to revolve. The correct clearance is—a free fit to a maximum of .003". It is very important that the gear be pressed onto the camshaft using the steel hub of the gear as a pressing medium and not any part out from the steel hub. Serious damage will be done to the gear if it is pressed on the

	Fig. 19—Using Puller to Remove Crankshaft Gear essary. To replace this gear a driver is essential so that the gear can be driven straight back on its seat accurately. , The camshaft gear, or camshaft timing gear, is a composition gear pressed into gear blanks under enormous pressure. After the blank has been made, the teeth and the inside hole of the gear are machined, the timing mark punched on it and the keyway cut. This gear together with the steel crankshaft gear provides long, quiet, trouble free life. If it becomes necessary to replace the camshaft gear, a sleeve to properly support the gear on its hub is necessary.
		Fig. 21—Checking Camshaft End-Play