Delete all your old messages to free space on your phone. 1  Go to Settings --> Messages. 2  Scroll down to Message History. Here, you can choose to delete all messages older than 30 days, or all messages older than a year old.  Confirm that you want to delete the old messages and attachments.
Well, the master cylinder is tasked with supplying hydraulic pressure to the braking system. So when you initially step on the brake pedal the linkage activates a piston within the system and this piston then displaces hydraulic fluid.
Wheel Cylinder The wheel cylinder consists of a cylinder that has two pistons, one on each side. Each piston has a rubber seal and a shaft that connects the piston with a brake shoe. When brake pressure is applied, the pistons are forced out pushing the shoes into contact with the drum.hen you apply the brakes, brake fluid is forced under pressure into the wheel cylinder, which in turn pushes the brake shoes into contact with the machined surface on the inside of the drum. When the pressure is released, return springs pull the shoes back to their rest position.