Master cylinder problem

Bernie Benz b.benz at
Mon Jul 24 19:44:26 EDT 2006


First, I don¹t think that your receiving the wrong master cylinder had much
to do with ³causing the front passenger side brake to freeze up.³

The MC has two independent circuits, Front is for the front wheels, rear is
for rear wheels. Both circuits go thru the ABS hydraulic modulator, but
that¹s a non issue relative to your Q, inasmuch as the lines to each front
wheel are in parallel, tying to the same point on the top of the ABS unit.

Lets start with the basics. How long has it been since, or have you ever
cleaned out the front and rear caliper hydraulics? Flushed the fluid at
least every 2 years since that full F and R hydraulic overhaul? If the
answer is NO, Never, here is your starting point. Don¹t touch the MC!


> From: "John S. Lagnese" <jlagnese at>
> Hi,
> I ordered and received my master cylinder. It turned out to be the wrong
> one. I'll go back tomorrow to try again.
> I don't see how this could cause the front passenger side brake to freeze
> up. It displays all of the symptoms laid out by others. It doesn't happen in
> winter, occurs almost every time when the car is hot, and goes away when the
> mc cools.
> What I don't see is if there are two lines coming out of the mc, how can
> one, but not two wheels be affected?
> Thanks,
> John 

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