Quote:
Originally Posted by tkeagle
Geezz, one thing after another. For some reason, brakes stopped working. I tried to do a quick fix, and just tighten up the brakes. No good. So guessing need to bleed the brakes. Booster, is less then year old. So don't think it's that. I've been told once, that due to the small booster, the YD tend to get air in the brake lines for no reason. I cant think of anything I've done to it, that would cause it to get air in the lines.
Maybe because it's been in a lot of water lately?
Anyone else have same issue? Brakes just going caput on ya?
|
For some reason getting unexplained air in the system has always been a problem. The yerf master is adequate enough. A master is measured in the volume of fluid it moves on each stroke. the yerf master moves enough fluid to fully extend the caliper piston. fluid pressure is irrelevant. hydraulic fluid exerts a measured amount of pressure regardless of size or volume. That doesn't seem to make sense because we think in terms of pressure. but it's a law of fluid dynamics. It's the area or volume that the fluid has to work against. some may argue this by saying the more pressure the more power or force but in reality pressure is only the ability to move fluid. for instance take a hydraulic motor.. give it 100 psi of pressure it will spin at 1,000 rpms. reduce that pressure by half it will spin at 500rpms but the motor toque is the same
IE:If a master moves fluid down a 1/8 line 2" on a stroke. it moves a 1" round caliper piston 1". The same master pushing on a 2" piston only moves it 1/2" it's the surface area of the piston the fluid has to cover that makes the difference. In both circumstances The Fluid pressure is equal! Absolute fluid pressure is achieved and both pistons apply the same amount of force. In a closed brake system when the master is compressed, equal force is applied to all areas, the inside of the lines, fittings, etc. The only thing that gives is the caliper piston. Air bubbles rob the system by creating more area the fluid works against. Enough air bubbles in the system the fluid looses the ability to move the caliper piston enough distance to force the brake pad against the rotor. Your brakes go soft, feeling as though you have no pressure.
So how does air seem to find a way into this system? Imo... it's the O-ring seals on the caliper piston and the wiper seal on the master push rod , If the system is not used for a few days or weeks the seals get stiff. After a stoke or two the seals loosen up but allows a microscopic amount of air to slip by until the seal is lubricated. After a time enough air gets in to start robbing volume. Cheap seals!