Brake bleeding on and off?

2005 FORD EXPLORER

200,000 MILES • 6 CYL • 4WD • AUTOMATIC

EHFOWLER

MEMBER
1 POST
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I've rebuilt all the brake lines. Installed new rotors and pads and rebuilt the front calipers. When I bleed the brakes, the pedal gets good and firm. I can't find any leaks. When I turn the engine on the pedal goes to the floor, the fluid reservoir stays full. Thanks in advance for your help.

Apr 13, 2023 at 11:57 AM

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JACOBANDNICKOLAS

AUTOMOTIVE REPAIR CONTRIBUTOR
110,190 POSTS

Hi,

There is a chance the master cylinder failed during the bleeding process. Under normal use, the plungers only travel a small distance within the bore. When you bleed the brakes and the pedal goes to the floor, often the plungers are damaged by dirt or corrosion in the untraveled area.

So, here is what I need you to do. Pump the brakes (engine off) until you get a solid brake pedal. Hold pressure for an extended period of time and see if the pedal slowly goes down.

If it doesn't, you likely got air into the hydraulic control unit which requires an automated bleed procedure with a scan tool.

Let me know about holding pressure.

Take care,

Joe

Apr 13, 2023 at 7:55 PM