Brake chatter

I am helping a friend with a 6A, with Cleveland brakes. The airframe has around 300 hours. Was working fine prior to condition inspection. I observed the condition inspection, done by a RV experienced A&P/IA. The disk appears in great shape, the pads appear at half life. They were not changed since he only expects to fly 50 hours this year.

After inspection, the right brake makes a howling sound when taxiing. You can hear it in and out of the plane. I took the wheel pant off yesterday and I had to use both hands to rotate the tire. Started to dis assemble the caliper and the drag went away. I noticed the solid aluminum brake lines (stock Vans) left some tension on the caliper not allowing it to "float". Fixed. The bearing feels fine after the brake tension was released.

The pins that the caliper floats on had a little slop, more than my Matco's. Everything else appeared normal. Elected not to change the pads since I thought I found the problem. Started reassembling and having the owner test the brakes multiple times while the wing was jacked up. Appeared ok.

As he started taxing back to his hangar, it started again. Did not jack it up again yet since it was getting late. The next time it comes apart we will put new pads on it. Not a difficult job, just frustrating not being able to find the problem.

Any suggestions?

Make sure the piston isn't sticking. That's the only other thing I can think of right off hand.

~Marc

Try grinding off the leading edge of the pads to a 45degree.

With the piston pushed all the way in and caliper installed with line connected, caliper should move with ease on its pins. Keep the pins clean and dry lubed.