Brakes

Suspension, Brakes, Tires, Wheels steeringetc..
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MODOG

Brakes

Post by MODOG »

My 71 swb has 2 resivour master cyl.When i got the truck it was making a
SSSSHHHHHHHHHHHH sound when I would step on the brake,I found that
the rear resivour was totaly empty then found a big hole in the rear rubber
brake line and replaced it and bled the brakes.That did'nt stop the ssshhhhhh
sound but slowed the loss of fluid.My dad thinks it's the boster but the other
day while fixing the rear tail light wiring I see the little splitter or junction box
on top of the rear axle is very wet.I looked to see how to fix it but no luck
need to replace while i'm there I will put all new lines in,but do'nt think that
will get rid of the SSSSSSHHHHHHHHH.Help!!!!!!

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FredM
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Post by FredM »

I'll bet it's your vacume booster making the noise
they get holes in the diaphram sometimes.
make sure the lines are tight at the little cap on the rearend, it
is a breather for your rearend, might need cleaned
ENJOY LIFE, --- It's the longest thing anyone ever does-- --

When seconds count, Help is only minutes away-----------------

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Hobcobble
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Post by Hobcobble »

I'd attribute that "whooshing" sound to a failing
master cylinder. The splitter on the rear axle is
very possibly held in place by the threaded tube
which serves as your axle vent. This dampness you
see could be a bit of 90W oil that found its way
out of the vent tube cap. You mentioned slowing,
but not completely stopping the loss of fluid?
have you thoroughly inspected all of your hard
lines and rubber hoses? Have you pulled the drums
and inspected your wheel cylinders?
John

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WD
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Post by WD »

I put a rebuilt manual brake master on my 69 awhile back. Same whoosh you describe. Mine has leaked since the day I installed it. Bad master. It leaks into the cab now too. Double check your system. Pull the master and look in the booster with a flashlight. I bet the rear master seal has failed and you have a booster full of brake fluid.
-WD
If I didn't build it, it ain't mine.

1949 Dodge B1B-108; 1969 D100-128; 72 Super Beetle; and a bunch of others...

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cowboy
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Post by cowboy »

modog, do you have power brakes ? your post never mention it , you can look up behind the brake pedel & see if fluid is leaking in the cab if so replace the master , if you have power brakes then do as fred said & go from there
:usa
cowboy Alvin Tx
67 w100 318 3spd
2005 Ram 2500 CC Diesel 4x4 lwb
LAND OF THE FREE
BECAUSE OF THE BRAVE

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Hobcobble
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Post by Hobcobble »

Yeah.... excuse my Friday night incompetance... the
booster.... more-so than the master cylinder, sounds
suspect, like Fred & WD mentioned :Thumbsup . Does
your pedal stay up?.... or does it tend to sag toward
the floor? If you haven't really scoped out your
entire brake system in a while.... get under your
truck and look at all the lines, connections, hoses, etc.. Also, pull your drums and look at the wheel
cylinders.... you may be bleeding fluid from more
than one location.
John

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