brake system lockup, all 4 wheels

Andrei Kogan akogan at MIT.EDU
Fri Mar 7 19:20:28 EST 2003

[ Picked text/plain from multipart/alternative ]

Could you explain to me how a loose cap  can make the brakes to lock up? I
cannot seem to figure this out.  Or do you think it just lets the fluid to
pick up a lot of moisture over a long time, which then makes it's way down
into the calipers, and then if the brakes start dragging it heats/ expands/
causes more drag/causes more heating??

I am having brake issues ( reverse of yours -- no braking, pedal in the
floor) and no apparent air in the lines..... must be the master in my  case


At 06:46 PM 3/7/2003 -0500, you wrote:
>So I go on Pizza Hunt for dinner(very good hunt, pizzas plentiful
>this season) and as I'm about 2/3rd of the way home, the car start
>slowing dramatically between shifts; I look down and realize manifold
>pressure's a lot higher than normal for cruising, etc....#$@!, must
>be the rear brakes.
>It gets worse. And worse.  And worse.  I get home, pop out, yep, nice
>warm something-is-roasting smell.
>I walk around and do the old chunk-of-snow-at-the-wheel test, and,
>not one, not two, not three, yes all four, that's right, all four,
>rotors are broiling hot.  As I watch, the car(ebrake off, tranny in
>1st) creaks a little and rolls backwards slightly.  Does this again a
>few seconds later.
>Last time I had a problem like this, it was the cap on the reservoir
>on my 5000, it was extremely loose.  I haven't checked this time, but
>I'm pretty sure the cap is just fine, I was in the engine compartment
>Master cylinder failure?  It's slightly below the min line(there's
>been some fluid leakage very recently, didn't get a chance to figure
>out where it went yet).  Also, recently, on one drive just a day or
>two ago, the pedal sunk half way very suddenly- hasn't done that
>since, although on the way home, the pedal got -really- soft.
>Gotta go out and move the car a foot or so back so I don't have
>massively warped rotors...
>So I guess the plan is to top it off and bleed the system...
>Sigh.  Happens without fail- right before an NEQ event or meeting.
>"They that give up essential liberty to obtain temporary
>safety deserve neither liberty nor safety." - Ben Franklin

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