Jason wrote:
>
>Okay, here's the situation:
>
>My brakes slowly dteriorated to nothing, so I got a brand new master
>cylander (couldn't even get the old one apart, and I didn't really want to
>second guess my brakes...), and installed it. Now, a new problem arises.
>The front calipers are way too tight. So tight, in fact, that there is
>major drag on the car, and the pads smoked on the test drive (I caught this
>early, so all should be well). My local MG specialist was kindof baffled,
>which surprised me: he usually knows the answer to a problem before you
>tell it. The only thing he could think of was bad caliper hoses. I
>replaced them, to no avail.
>
>Here's a little more info. It almost seems like there's TOO much pressure
>to the calipers: When I bleed them (pump a few times, and hold), the fluid
>shoots out like it's jet propelled <g>. Is this normal? The fluid from the
>rears, on bleeding, doesn't have nearly as much force.
I like Mikes advice about swapping back the old master. It is a good
check to see if the lines are at fault. But you should expect that the
old master could be so worn that it may not give the same symptoms even
if the master is not at fault.
Possible problems:
1) The rear brake hose is restricting flow to the rear cyl's.
2) The proportioning valve could have a problem and be blocked by debris.
(remember you couldn't get the old one apart.)
3) The calipers themselves. If you just replaced the pads and they have
been on there for quite some time, (this is my best guess.) Unless the
fluid is being blocked from returning to the master is is the fault of
the piston seals that they are not returning. To TEST this you can try
the following; set up to do a bleed on one of the calipers. Bleed it
once with pressure on the pedal. Then pump the pedal once or twice and
take you foot OFF the pedal. Give it a few seconds, (5-10) and open up
the bleeder. If it squits out you know you have pressure built up. If
it trickles out, as it should due do gravity, then I'd have the calipers
rebuilt/replaced.
Good Luck/Saftey Fast!
"If uniqueness makes us who we are, why be like everyone else?"
'73 MGB (under restoration)
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