Art sez-
<snip>
> Brake pedal is hard as a rock.
>
> When I open ANY (one at a time) of the four wheel bleeder valves and push
on
> the pedal fluid comes out. But only when I push the pedal. There
appears to
> be no sound of air going into the system when I release the pedal and
tighten
> the bleeder valve at any of the wheels. After doing this and tightening
the
> valve down the wheels spin freely. (The handbrake works on and off if I
apply
> it after I tighten the valve but before I again push the pedal - so it
appears
> that the handbrake is not binding). If, after tightening the wheel
bleeder
> valve I press the pedal, the pedal is hard and brakes lockup again. I
assume
> that this means no air was sucked back into the system when the valve was
open
> and the pedal released.
>
> My assessment is that it is the master cylinder which is not releasing
the
> pressure in the system. But I am concerned about the restrictor valve
which
> is located in the engine compartment at the 4 way connector (MC, front
left,
> front right, and rear). The three flexible hoses appear to be rigid -
they
> were replaced with new ones about two years ago. Any way to check the
> restrictor valve or do they not go bad? - yeah! :-). And how can I be
sure
> that the hoses have not collapsed inside?
>
> I can get an MC rebuild kit but hate to rebuild it if the restrictor
valve or
> a hose is the problem (according to the manuals I'll have to take both
brake
> and clutch MC's out of the car to get at the brake MC). It also appears
that
> restrictor valves are not available from the big three (TRF, Moss and
VB).
>
> So, to be honest, I'm getting that paralyzed feeling. Need to get this
done
> this week or I'll have to wait several months.
<snip>
I'll agree that the master is probably not releasing the pressure, but the
valve at the four way connector doesn't sound like the problem. I'd look
very closely at the "free play" at the pedal/actuating interface as it goes
into the master cyl. Adjust the clevis so that there is too much play here
and try it again. The master cylinder has a "port" in it that allows the
pressure to bleed back to the reservoir. If the rod holds the piston too
far
into the cylinder, it does not uncover this port and allow the pressure to
bleed off. This is not that uncommon a problem just after a cylinder
rebuild, or pedal removal. If you have not done any "remodeling" here, it
may be an indication of the seal heading South and not allowing the piston
to return far enough to uncover the port.
Yes, I ...I mean you...can have this problem on a clutch master too...
Nick in Nor Cal
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