Expert in Brake Hydraulics Needed

[Michael C Henry]

That is pretty much what I have for front brakes. I have the Jag inboard rear brakes. I'm using two Tilton 3/4" master cylinders with an adjustable balance bar from the pedal and between the two master cylinders. When routing the brake lines take great care in not creating places where air can collect in a high point in the middle of the system. Normal operation of the brakes you are moving a small amount of fluid in a column of fluid with each stroke. The master cylinder pushes fluid column to the brake caliper cylinders. The piston will move towards the rotor. The packing will slide on the caliper piston to a point and then twist with the inner surface of the packing cling to the piston and the outer edge still confined in the caliper bore grove causeing a twist in the packing. When released, the packing around each piston in the calipers will try to twist back to its neutral point, that is the release of the brake shoes. A verry small amount of fluid moving back and forth. What happens when not in use air that in system will collect at the high point. When you go to bleed the system you are trying to flush fluid containing that air bubble. All the while, that air bubble is trying to return to that high point. The farther that high point or multiple points are from the end ( the bleeder point ) the more fluid will have to be flushed in an effort to carry that bubble out of the system. My brake master cylinder resivoir is mounted on the firewall the highest point in the system. My master cylinders are below the floor boards. The high pressure line then falls a small amount to follow the frame member forward then splits and goes to each front caliper with the caliper being the highest point at the front end of the brake system. Generally most air in the system works it way out of the system through the master cylinder and escapes in the resivoir letting gravity work for you. Bleeding is only necessary to remove air in system at the higher points up front near each caliper. Remember the plumbers law "**** flows downward". If you have a higher collection point in your system it may take a power bleeder to push out enough fluid out to get that air bubble out of your system. Then (for the most part) your done . No more air will get into fluid system unless you have leak or you interupt your system as in a major repair.
You can replace the brake pads by just pushing the caliper piston inward (one caliper at a time) and not seperating the brake line. I pry against the old pads being replaced pushing the piston inward. then I unbolt the caliper. Tie the caliper up , don't let it hang by the hose. After each caliper is loaded with the new padsand bolted back in place, operate the pedal to move the fluid refilling the caliper bring the pads into contact whith the rotor. If you haven't been refilling the resivoir the fluid returned to the resivoir should not overfill and should be at the correct level. If you push both calipers back at the same time chances are that that amount of fluid will over fill the resivoir and cause a spill.