wrote in message
...
On Fri, 24 Feb 2006 16:52:10 GMT, Nathan Young
wrote:

snip

Question: Are the symptoms I describe part of normal brake wear? Ie
the pad wears down, and now the piston has to extend further? I don't
understand why this would cause softness though...

When the master cylinders are static, fluid can flow through them to
make up the difference in volume from the pistons extending from
pad/rotor wear.



Sounds to me like you've got some air trapped in the one side, you are
compressing with the toe cylinder, and also with the hand cylinder
(via the route described above).


As Mr. Cutter suggests, air is the typical cause.

But, if you have a lot of runout in the disk it will push the pad back too
far and the first time you press the brake, it will take a lot of travel.
But you can usually also feel the brakes pulsing when it gets that bad.

Another posibility is something is loose (e.g. wheel bearing) and the rotor
wobbles when you go around a corner - again the first time you press, it
won't be firm. I had a van that would flex enough that when you cornered
real hard, the brakes would be soft the first time I went to use it. I guess
a 3/4 ton van just isn't intended to be driven like a sports car :-)

If the problem is rotor flex / movement, once you press the brakes they will
remain solid as long as you don't move the airplane. If they get spongy
after sitting still for a bit, the problem is most likely air - not wear.

--
Geoff
The Sea Hawk at Wow Way d0t Com
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