2-4 GROUP 2B rakes The torque measurement must be made relative to the centerline of the wheel. Tighten the lock nut. 4. Make sure there is no drag when turning the rear wheels. 5. Lower the vehicle. Remove the torque wrench and Tool T66L4204L, if required. Install the wheel attache ing nuts and torque them to specifi~ cation. Install the wheel cover. POWER BRAKE MASTER CYLINDER PUSH ROD ADJUSTMENT The push rod is provided with an adjustment screw to maintain the cor- rect relationship between the booster control valve plunger and the master cylinder pistons. Failure to maintain this relationship will prevent the mas, ter cylinder piston from completely releasing hydraulic pressure and can cause the brakes to drag. or cause ex- cessive brake pedal travel. #16 GAUGE SHEET STEEL o. 980 ~0995 H 'IZOBVC FIG. 6Push Rod Gauge Dimensions To check the adjustment of the screw, fabricate a gauge of the dim- ension shown in Fig. 6. Then place the gauge against the master cylinder mounting surface of the booster body as shown in Figs. 7 or 8. The push rod screw should be adjusted so that the end of the screw just touch- es the inner edge of the slot in the gauge. Do not set up side forces on the push rod. Side forces may break AIR FILTER ADJUSTMENT H1349-A FIG. 7Push Rod Adjustment Midland-Ross the valve plunger. This is an approximate adjust- ment only. The push rod should not move more than 0.015 inch as it con- tacts the master cylinder piston. N0 niovement (exact contact) is ideal. HYDRAULIC SYSTEM BLEEDING AND CEN.TRALIZING OF THE DIFFERENTIAL VALVE When any part of the hydraulic system has been disconnected for re- pair or replacement. air may enter the system and cause spongy pedal action. Bleed the hydraulic system after it has been properly connected, to be sure that all air is expelled. MANUAL BLEEDING The primary and secondary (front and rear) hydraulic brake systems are individual systems and are blcd sep- arately. Bleed the longest line first on the individual system being servic- ed. During the complete bleeding op- eration. DO NOT allow the reser- voir to run dry. Keep the master cyl- inder reservoirs filled with Rotunda FluidiExtra Heavy Duty wlart Num~ ber C6AZ-l9542-A. The extra heavy duty brake fluid is colored blue for identification purposes. Do not mix low temperature brake fluids with the specified fluid during the bleed- ing operations. Never re-use brake fluid which has been drained from the hydraulic system. I. Loosen the bleed screw located on the side of the master cylinder. Do not use the secondary piston stop screw, located on the bottom of the master cylinder to bleed the brake illllllllllllllllil illllllllllllllli H 1330- B FIG. 8~Push Rod Adjustment Bendix system. Loosening or removing this screw could result in damage to the secondary piston or stop screw. 2. To bleed the secondary (rear) brake system, position a suitable 3/8 inch box wrench (Fig. 9) on the bleed- er fitting on the brake wheel cylin- der, Attach a rubber drain tube to the bleeder fitting. The end of the tube should fit snugly around the bleederfitting. APPROXIMATELV 45 H1300A FIG. 9Wrench for Bleeding Brake Hydraulic System 3. Submerge the free end of the tube in a container partially filled with clean brake fluid. and loosen the bleed- er fitting approximately 3/4 turn. 4. Push the brake pedal down slowly through its full travel, Close the bleeder fitting. then return the pe dal to the fullyereleased position. Re- peat this operation until air bubbles cease to appear at the submerged end ofthe bleeder tube. 5. When the fluid is completely free of air bubbles, close the bleeder fitting and remove the bleeder tube. 6. Repeat this procedure at the brake wheel cylinder on the opposite side. Refill the master cylinder reser- voir after each wheel cylinder is bled