Push that brake pedal now!

[Guest DodgeKCL]

Many of you ask questions about rebuilding leaking brakes but did you know that the biggest cause of leaking brakes is the inactivity that occurs during the Winter storage. The rubber cups stick and a ridge is formed by the bores drying out from the cups not sliding back and forth on the bores and wetting them and the cup lips. Every month ,on the same day I put my trickle charger on my batteries, I push the brake pedal several times to activate the system. An old mechanic put me on to it. He said he used to open the door and kick (!) the pedal a couple of times when walking by if he couldn't remember the last time he did it. Worked for him. It wets the cylinder bores, both master and wheel, and keeps rust from forming on the 'outside air' side of the cups and keeps the cups from sticking and chipping from sitting still for 5 or 6 months.

Over the years I've wondered why it's necessary but I've assumed the automotive engineers designed the system with the thought in mind that the brakes would be used at least once a week if not more. They never thought they would sit idle for months at a time.

A further thought about batteries. I store all my batteries, lawn tractor, wood splitter, antique vehicle, in the freezing Canadian cold in an unheated garage beside my shop. A battery looses 50% of it's charge per month through self discharge in 70 degree/21 C Summer temperatures but only 1% under 32 F/0 C. in Winter. It actually goes to sleep. The chemical reactions literally stop. I trickle charge my batteries once a month for a day to alleviate any discharge that may have occurred. I get 12 to 15 years out of my batteries. One of my last 6 volters lasted 12 years. It's replacement went in May 2002 and will still be on the road in 2011. Works for me.

Edited January 7, 2011 by DodgeKCL (see edit history)

[Rusty_OToole]

Old brake systems, before about 1975, had a residual pressure valve. Its job was to hold a slight amount of pressure in the system to press the seals tight against the cylinders. After a while the pressure oozes away, the fluid leaks out and when you press the brake pedal it goes to the floor and stays there.

If you pump the pedal once in a while it keeps things moving and keeps a little pressure on the system so the seals don't leak.

When an engineer sits down to design a car he is thinking in terms of not having it wear out prematurely under hard use. He is not thinking what will happen if it sits around for months or years.

I think at one time owner's manuals had instructions for long term storage as many owners put their cars up for the winter. This idea went out in the thirties.

[Guest Albert]

rusty,, All drum brakes still have residual valves,, just have to know where they are, my 97 olds i have two valves midway down the car, one for each rear drum..