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I changed the seals in the master cylinders of my M20F, put fancy Teflon brake hoses on my brakes and changed the brake pads. After many tries of pressure bleeding from the brake caliper up and from the master cylinders down I still had mushy brakes. I know that there are many more Mooney pilots that have experienced the same problems bleeding their brakes. I consulted some mechanic friends and after some fought after success the brakes work as they should. This is what I found out. I hope it helps you avoid the immense frustration of bleeding Mooney brakes. Note: My aircraft does not have brakes on the copilot side. The brake line comes from the reservoir to a T above the master cylinders then to each respective master cylinder and then downward toward the brake calipers. If each side is bled individually, an air bubble can shuttle at the T and not bleed out. Air can also hide in the master cylinders. After consulting the maintenance manual and some Mooney mechanics who agreed that it was at times extremely frustrating to bleed Mooney brakes, more that one offered this advice. "If you pressure bleed from both the calipers up to the reservoir at the same time and jiggle the tops of the brake pedals during the process you have a very good chance of eliminating all of the air in system." You can purchase 1/4 inch clear plastic tubing from many hardware stores along with a T fitting so that you can bleed both brakes at the same time with one pressure vessel. If you have any other sure fire techniques for bleeding the brakes I am all ears but this one works great. PS Remember to run a clear plastic line from the top vent on the reservoir to an empty brake fluid can so you can keep an eye on the bubbles and avoid getting overfilled fluid on the cockpit floorboard. I will attach photos of the process later.