Re: Stuck brakes

Posted by TOOLS1 on Apr 23, 2011; 5:39pm
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/Stuck-brakes-tp2846892p2855484.html

I just realized there are two different Jammin's asking questions here
Lets see here. How do hydraulic disc breaks work? When you squeeze the lever. It pushes a small piston past a very small hole in the reservoir closing it off. Now the sealed off fluid only has one way to go. Through the lines to the caliper. Once there it pushes against a larger piston. The larger piston then pushes the break pads against the rotor. The caliper is mounted, so that it can move, and center itself against the rotor. This way it applies equal pressure on both sides of the rotor. When you release the lever. the small piston travels back across the very small hole releasing the pressure. If gunk, or corrosion has built up here it will plug the hole, and not allow the pressure to release. At this same time the piston in the caliper must release pressure on the pad's, and rotor. The caliper must be free to move, and release the rotor. Also the the piston in the caliper must be free to move. The rubber O-ring is supposed to expand out when the piston moves out. Then when the pressure is released it is supposed to pull the piston back a fraction of an inch to release the pads from the rotor. If the piston has corroded, or gunk built up. The piston will not be pulled back that fraction of an inch to release pressure on the pad's, and rotor.
Hope this explains it.
TOOLS