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.
Drum brake masters have 10 lb residual valves at the outlet to keep a residual pressure on the drums. If you use a drum brake master for disc brakes you would move an insufficient volume of fluid and the disc brakes would drag because of the residual valves.