Crown Automotive Power Brake Boosters

Does the booster have to be adjusted before install? I have installed it and now my brake pedal has a small amount of play in it. This has caused my brakes to drag ( psi use to be 5 psi, now it jumps as high as 30 psi, but when I pull up on the pedal, it goes back to 5 psi)

Asked by Felix from Va on

Hey Felix, 1. Remove the master cylinder reservoir cap or cover. 2. While an assistant slightly depresses the brake pedal, watch for fluid to erupt in the reservoir when the pedal is depressed 3/8” to 1/2”. This indicates correct push rod length. On dual system master cylinder, fluid may spurt only from the front reservoir. 3. If the pedal travels more than 1/2” before master cylinder fluid erupts, the push rod is too short. If nothing happens no matter how far the pedal is depressed, the push rod is probably too long. 4. To adjust the push rod length, first remove the master cylinder from the power booster. Using a pair of pliers, turn the push rod adjusting not in to shorten and out to lengthen the push rod. 5. If the push rod is nonadjustable, use shims between the master cylinder and power boosterto shorten it. If too short, remove existing shims or remove the push rod from the booster and replace it with one of the proper length. 6. Install the master cylinder onto the power booster and recheck push rod length. 7. Connect the vacuum hose(s) to the power booster. 8. Reconnect the ground cable to the battery. 9. Make sure the braking system works correctly before moving the vehicle. If the pedal is soft or has excessive travel, it may be necessary to bleed the entire braking system. I hope this answer helps and earns your business. Thanks for your question.

Answered by Devin B. ext 835 from Va on