My "distribution valve" under the master cyclinder doesn't seem to
work. I found if I open the front or rear, I loose all breaking, no
matter how many times I pump. My brakes are manual drum all the way
around. I've tried replacing the master cylinder (it's dual resevoir
of course), wheel cylinders, etc. No leaks. California Car.
If anybody has one they want to sell (maybe someonewho converted to
disc?) please email me and let me know how much you'd want for it.
David ( email@example.com)
(Michigan - north west of Detroit)
Email address is just one I created long ago for spam. There is no
Richard. I just haven't gotten around to creating a new one. This is
my first newsgroup posting.
Even though you have separate systems for the front and rear, it is normal
for your pedal to go to the floor if either system is opened up. That in
itself doesn't mean anything is wrong with your distribution block. - Gary
Interesting. I'm at a lost to understand. Seems like that's the idea,
that if I lost front or rear brakes that the other would still work.
But even after being bled, the brake pedal seems very low (almost to
the floor). I've tried two new master cylinders, Thoroughly bench bled
the Master Cylinder, blead the lines (both 2 person and one person
with a vacuum gun), and there are no leaks anywhere (not even at the
wheel cylinders). And I think I put new wheel cylinders on in the last
couple years. If I press a second time the brake pedal comes up a
little higher (enough to stop me from rearending the car that panic
stopped in front of me). But if I plug the right front hydraulic line
(where it leaves the distribution block) then the peddal comes WAY up
where it should be (I haven't tried plugging front left because I
don't have the larger size plug for it).
I've ordered new front wheel cylinders, hoses, and (pre-bent) lines
out of despiration (should be here by Tuesday). But all the existing
ones look to be in good condition. Suspicious though that the two
front wheel cylinders seem to have two different size bleeder screws.
I think one takes a 3/16 wrench and the other 5/16. Not sure the screw
itself is different, just the hex. Anyway, will replace with two wheel
cylinders from same place see what happens.
Thanks for your reply and if you have any other comments.
If the brakes have been bled sufficiently to remove all air from the system
then my next best guess is that the self adjusters aren't adjusted properly,
that could cause a low pedal.
Actually, it's combination valve from what I remember. Proportioning valve is
an industry-wide term that's evolved from it, but it's not how it's known in
the parts books.
In the same respect, GM still calls an alternator a generator, or in some
literature a Delcotron, which is the Delco Remy version of the unit.
Joe--ASE Certified Parts Specialist & 10th Ann.Club Tech Director
'80 Carousel Red Turbo T/A, 26k orig.
'79 "Y89" 400/4 speed 10th Ann. T/A, 57k orig
'84 Olds 88 Royale Bgm 2 dr, 307 "Rocket" (lol), 141k and still going....
'80 T/A project car...
I believe it's called a distribution valve for Drum brakes (x4).
I believe it's called a proportioning valve if there are disc brakes
in the system where you want more pressure initially applied to one
end (derived from the word "portioning" I presume).
I'm not an authority but the articles I've read on converting drum
brakes to disc brakes talk about replacing the "distribution valve"
with a "proportioning valve". And articles that aren't specific to
disc/drum, us a combined reference of "distribution/proportioning
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