Bench Bleeding Master Cylinder
WARNING: This page does not describe the selected car, but rather 16 other vehicles, including the 1985 Mercury Topaz, 1985 Mercury Marquis, 1985 Mercury Lynx, 1985 Mercury Grand Marquis, and 1985 Mercury Cougar. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Bleed tubes must have a residual pressure check valve installed to keep tubes from siphoning brake fluid.
- Master cylinder must be bled before bleeding entire system. Master cylinder bleeding may be done on vehicle. Preferred method is to bleed master cylinder on bench. If master cylinder has a bleed screw, bench method should still be used. When master cylinder is installed on car, use bleed screw as a final check for trapped air.
- Place master cylinder level in a vise. Attach bleeding tubes to cylinder. Fill reservoirs with fluid so that ends of tubes are covered as shown in Fig 1 . Tubes attached to disc brake outlets must have residual pressure valves installed over ends. This will keep tubes from siphoning.
- Stroke piston in bore with a wooden stick or dowel until bubbles no longer appear at ends of tubes. Remove tubes and plug the master cylinder disc brake outlets to keep fluid from draining.