Brakes - Minor service operations
BRAKE PEDAL AND BRACKET (STANDARD BRAKES)

The brake pedal is suspended from a mounting bracket under the instrument panel. Nylon bushings between the pivot bolt and the pedal eliminates periodic lubrication. The pedal is connected to the master cylinder push rod by a clevis. The brake pedal or bracket can be removed as shown in Figs. 11-7 and 11-9.

To install, lubricate inside of bushings,- clevis pin and stop lamp switch bolt head with lubricant,, Part No. 567196. Torque pivot pin nut, on 33, 34 and 35 series, 10 to 18 ft. lbs. Adjust brake pedal as outlined under STANDARD BRAKE PEDAL ADJUSTMENT.

Fig. 11 -9 Standard Brake Layout (33, 34, 35, 36, 38 & 39 Series)

HYDRAULIC SYSTEM

BLEEDING OF LINES

Whenever a line is disconnected from any wheel, it is necessary that the wheel cylinder be bled. If the hydraulic line is disconnected from the master cylinder or the brakepedal has a spongy feeling, each wheel cylinder must be bled to expelair from the system.

NOTE

Power brakes can be bled in the same manner as a standard brake system. If pressure bleeding equipment is not available, DO NOT use the vacuum assist. With the engine shut off, the vacuum reserve should be depleted by applying the brakes several times before starting the bleeding procedure.

The system can be bled manually or by using pressure bleeding equipment. The correct sequence for bleeding is left front, right front, left rear, right rear. On 30, 31 and 32 series with power brakes, bleed the master cylinder bleeder first. To bleed the system, the following procedure is recommended:

  1. If brakes are to be bled manually, fill the brake reservoir with Brake Fluid, Super No. 11 and KEEP AT LEAST ONE-HALF FULL OF FLUID DURING THE BLEEDING OPERATION.
  2. If brakes are to be bled with pressure equipment, connect the tank to the brake reservoir and raise the pressure in the brake system to 20 to 30 psi.
  3. Attach Bleeder Tube J-7779-2 to bleeder valve. (Fig. 11-10) THE TUBE MUST HANG SUBMERGED IN A CLEAN CONTAINER PARTIALLY FILLED WITH BRAKE FLUID, SUPER NO. 11 DURING THE BLEEDING OPERATION.
  4. Unscrew bleeder valve three-quarters of a turn with a wrench such as J-21472 and watch flow of fluid from bleeder tube. When all air bubbles cease to appear and fluid is clear, close bleeder valve.
  5. Remove bleeder tube.
  6. Repeat steps on the remaining wheel cylinders if the entire system is to be bled.
  7. If the brakes were bled manually, check fluid in the reservoir and replenish if necessary, after the bleeding operation has been completed.

Fig. 11-10 Bleeding Brakes

NOTE

If brakes are bled without the aid of pressure equipment, the brake pedal must be operated during this operation to force the fluid from the bleeder hose, To do this, open the bleeder valve, fully depress the brake pedal, then slowly release pedal until it is in the fully released position. Continue operating pedal until fluid, containing no air bubbles, emerges from bleeder tube. Close bleeder valve.
ATTENTION

Use extreme care to keep mineral oil or grease from coming in contact with hydraulic parts.

FLUSHING HYDRAULIC SYSTEM

Whenever mineral oil has been introduced into the hydraulic system, the entire system must be thoroughly flushed with brake Flushing Fluid and all rubber parts must be replaced. The brake Flushing Fluid is introduced into the master cylinder reservoir and expelled at each wheel cylinder in the same manner as the bleeding operation (See BLEEDING OF LINES).

When flushing is completed, bleed the hydraulic system with Brake Fluid Super No. 11 until all flushing fluid and air is expelled from the lines.