1942 - 1947 Chevrolet Shop Manual



	*2-8*

	These shock absorbers are also mounted on the car frame side member and the operating arms connected to the axle through suitable linkage. While this linkage varies in construction between front and rear installation, operation of the two shock absorbers is identical. The method of mounting the front shock absorber on passenger car models is shown in Fig. 10, and that of rear shock absorbers in Fig. 11. A detailed description of the front shock absorber link attachment to the front suspension is given in Section 3 of this manual.	The upper piston moves to the right, Fig. 9, displacing the fluid in the rebound cylinder. In slow action, the fluid flows only through the orifice of the rebound valve into the compression end of the compression cylinder. During rapid action the rebound valve is lifted from its seat and the fluid is forced into the compression cylinder. At the same time the intake valve of the compression piston opens allowing fluid to pass from the reservoir into the cylinder thus compensating for any loss of fluid between piston and cylinder walls of the rebound cylinder. OPPOSED CYLINDER DOUBLE-ACTING SHOCK ABSORBERS INTERNAL VALVE TYPE A cross section view of the opposed cylinder double-acting type shock absorber is shown in Fig. 12. This is one of the types available as special equipment on truck models.
	TAPERED HOLES IN ARM AND ANCHOR PLATE TAPERED LINK PIN VULCANIZED TO RUBBER IN LINK EYES

	Fig. 11—Passenger Car Rear Shock Absorber Mounting The rear shock absorber arms are attached to a link incorporating tapered link studs vulcanized to rubber grommets in each eye, Fig. 11. The tapered link studs fit horizontally into a tapered hole in the arm and vertical section of the axle fitting. Hexagon nuts hold the studs securely in position. Operation Upon compression of the car springs, the arm moves upward on the compression stroke forcing the piston in the compression cylinder, Fig. 9, toward the right. For very slight or slow axle or wheel movement, the fluid flows only through the orifice of the compression valve, as indicated by the black dotted arrow, and into the rebound end of the shock or rebound cylinder. Under rapid movement of the axle or wheels the pressure lifts the valve from its seat by compressing the compression valve spring, thus forcing the fluid into the rebound cylinder. At the same time, the intake valve of the rebound piston opens, allowing fluid to flow from the reservoir into the rebound cylinder. This is to compensate for any loss of fluid between piston and cylinder walls from the compression cylinder into the reservoir. During the rebound stroke, or as the arm moves downward, the direction of fluid flow is reversed.
		Fig. 12—Opposed Cylinder Double-ActIng Shock Absorber with Internal Valves Inside of the body and pressed on the shaft is a cam which bears against one piston during compression and the other during rebound movement. The two pistons are held together by two screws, one in each piston, that pass through one piston and thread into the other. The fluid reservoir is the space surrounding the shaft and cam inside the body, and an easily accessible filler plug is located in the upper part of this chamber. An end cap and plate with gasket is threaded over each end of the body and must be removed for making valve changes. On this type of opposed cylinder shock absorber the relief and intake valves are both placed in the pistons. The rebound and compression valves operate as main control valves and also as inlet valves for the return of fluid to each cylinder, Operation- The shock absorber unit comprises one rebound and one compression piston, the rebound piston being fitted with a spring-loaded rebound valve