Brake Bleed Q: trois

Bernie Benz b.benz at
Wed Sep 8 16:29:42 EDT 2004

From: SuffolkD at

The RR piston worked out under pedal pressure (test) during the R&R
disassembly AND I learned about the ratching of the E brake mechanism affect
to the piston during disassembly.  The hydraulic principles worked fine
then.  No frozen caliper (on the guide pins) and no frozen piston: from
either pedal effort or Ebrake lever ractheting.

Scott,  If the RR had 1/3 pad thickness remaining and the LR was to the
backing plate, both starting new at the same time, either the LR is gummed
up and not retracting or/and the LR has been frozen for a portion of its
life.  The pistons must be free enough that the 0-ring seal can retract the
piston, a very small force.

Agreeing with you on some of these points may put a feather in your cap (
you knowledgable devil you :-) ) but it won't give me the answers to "WHY?"
Particularly to the MC and the lack of fluid coming out while draining the
rear calipers using the bleeder screws.
When a complete overhaul will correct the entire brake systom performance
issue and possibly mask the precise cure, that's why I seek individual
points of the system to figure out what is happening.

Scott, Your problems are virtually impossible to diagnose effectively if you
don't know of the internal conditions of the system.  I didn't say that "a
complete overhaul will correct the entire brake system" but it will
certainly eliminate the most likely causes of your problem.


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