Dynasty L4-153 2.5L SOHC (1988)
Brake Bleeding: Service and Repair
Booster Bleeding
The anti-lock brake system must be bled any time air is permitted to enter the hydraulic system, due to disconnection of brake lines or hose for service. It
is important to note that air in the hydraulic system will not cause a spongy pedal feel or additional pedal travel. The Bosch anti-lock brake system
monitors booster piston travel and booster pressure and may set a diagnostic trouble code, due to air in the brake system.
Booster bleeding must be performed whenever the pressure hose, return hose, or pump/motor is replaced. Also, when the reservoir is emptied or
removed.
1.
The hydraulic accumulator must be depressurized, see DEPRESSURIZING HYDRAULIC ACCUMULATOR.
2.
Connect all pump/motor and hydraulic assembly electrical connections if previously disconnected. Be sure that all brake lines and hose
connections are tight.
3.
Fill the reservoir to the full level.
Bleeding Hydraulic Assembly
4.
Connect a transparent hose to the bleeder screw location on the right side of hydraulic assembly. Place the other end of hose into a clear container
to receive brake fluid.
5.
Open the bleeder screw 1/2 to 3/4 of a turn.
6.
Turn ignition switch to the "on" position. The pump/motor should run, discharging fluid into the container. After a good volume of fluid has been
forced through the hose, an "air-free flow" in the plastic hose and container will indicate a good bleed.
7.
Turn off the ignition switch.
If brake fluid does not flow, it may be due to a lack of prime to the pump/motor. Try shaking the return hose to break up air bubbles that may be
present within the hose.
Should brake fluid still not flow, turn off the ignition switch. Remove the return hose from the reservoir and cap nipple on reservoir. Manually fill
return hose with brake fluid and connect to reservoir. Repeat steps 6 and 7.
8.
Remove hose from bleeder screw. Tighten bleeder screw to 7.5 ft.lbs. (10 N-m). Do not overtighten.
9.
Top off reservoir to correct fluid level.
10.
Turn ignition switch to the "on" position. Allow pump to charge accumulator. It should stop after approximately 30 seconds.
