The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 05-28-2008, 11:18 PM   #1
stanglifemike
Registered User
 
stanglifemike's Avatar
 
Join Date: Jan 2008
Location: Carrollton, GA
Posts: 43
HELP!! Brakes went out!!

The pedal is just going to the floor now. I've always had pump it some, and some times at a redlight, the pedal would go to the floor after a minute or so, and I would have to repress the brake pedal and all was well. Yeterday though, on the way home I had nothing. I was near the neighborhood so I was able to get it home and into the backyard. I pulled the front wheels and loosened the line at the caliper. I had my daughter push the brake pedal and fluid was coming out just like it should. So, do you think its my calipers? What are the chances of both front calipers going out at the same time though?? Could it be the booster? Please help, and thanks for any thoughts
__________________
71 C-10
98 Mustang GT
06 Mustang GT

Last edited by stanglifemike; 05-28-2008 at 11:19 PM.
stanglifemike is offline   Reply With Quote
Old 05-28-2008, 11:39 PM   #2
michael bustamante
Senior Member
 
michael bustamante's Avatar
 
Join Date: Sep 2007
Location: Albuquerque NM
Posts: 7,848
Re: HELP!! Brakes went out!!

sounds like the master cyl. to me. those are all the symptoms
__________________
1967custom
michael bustamante is offline   Reply With Quote
Old 05-28-2008, 11:43 PM   #3
stanglifemike
Registered User
 
stanglifemike's Avatar
 
Join Date: Jan 2008
Location: Carrollton, GA
Posts: 43
Re: HELP!! Brakes went out!!

So brake fluid would be going to the calipers even though the master cylinder went out?
__________________
71 C-10
98 Mustang GT
06 Mustang GT
stanglifemike is offline   Reply With Quote
Old 05-28-2008, 11:50 PM   #4
motopatzo
Registered User
 
motopatzo's Avatar
 
Join Date: Oct 2006
Location: maple ridge, b.c., canada
Posts: 190
Re: HELP!! Brakes went out!!

If your brake fluid is at normal capacity, I would suspect the master-cylinder.
motopatzo is offline   Reply With Quote
Old 05-28-2008, 11:51 PM   #5
71tahoe
Registered User
 
71tahoe's Avatar
 
Join Date: May 2006
Location: Jonesboro, AR
Posts: 916
Re: HELP!! Brakes went out!!

Brake fluid under no pressure would still flow from the master cylinder. Once resistance is met in a pressurized system, the fluid pressure will just balance in the MC. (no pedal)
71tahoe is offline   Reply With Quote
Old 05-28-2008, 11:51 PM   #6
Longhorn Man
its all about the +6 inches
 
Longhorn Man's Avatar
 
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,693
Re: HELP!! Brakes went out!!

You need to step back and look over the whole system.
Park it on dry pavement if you can.
Check the master clylinder... is it full... on both halfs?
When you top it off (I'm gonna assume 1/2 of it is bone dry) and pump the pedal, do you hear fluid splattering?
Are you seeing any puddles forming?
look on the back side of your tires... are any of them wet?

There's a LOT more to it than calipers up front and a master cylinder, and any guesses with what little info you gave us... is nothing more than a guess.

Your initial problem;
Quote:
I've always had pump it some, and some times at a redlight, the pedal would go to the floor after a minute or so, and I would have to repress the brake pedal and all was well.
only indicates having a little air in the system. So this new problem, is a new problem.
Longhorn Man is offline   Reply With Quote
Old 05-28-2008, 11:51 PM   #7
PanelDeland
I am a Referee of life.
 
PanelDeland's Avatar
 
Join Date: Jun 2000
Location: Greensboro N.C.
Posts: 13,993
Re: HELP!! Brakes went out!!

"Usually" when a MC goes 'out' it is bypassing fluid around the piston in the MC.If that is what's happening then the fluid will flow out the line or bleeder.This is because the fluid will flow thru the path of least resistance.If you want a sure check you will need to hook a pressure guage to the system.
If you had no brakes then your rears are also not working.
__________________
The 47-present Chevrolet and GMC Truck Message Board Network,it's owners,moderators,members,and associates of any type should not be held responsible for my opinion.
You can't fix stupid,not even with duct tape.
"My appearance is due to the fact that "GOD" does punish you for having too much fun!"
Barrett-Jackson has perfected alchemy,they make rust into gold!
"You can lead a horse to water but you can't saddle a duck"
"Cleverly disguised as a 'Responsible Adult'
"Sometimes your Knight in shining armor is just a retard in tinfoil"
PanelDeland is offline   Reply With Quote
Old 05-28-2008, 11:52 PM   #8
stanglifemike
Registered User
 
stanglifemike's Avatar
 
Join Date: Jan 2008
Location: Carrollton, GA
Posts: 43
Re: HELP!! Brakes went out!!

OK cool, thanks for the quick responses guys!! Is it simple to swap out, or anything tricky I should look for. Any special tools, etc..
__________________
71 C-10
98 Mustang GT
06 Mustang GT
stanglifemike is offline   Reply With Quote
Old 05-28-2008, 11:53 PM   #9
hdflstf
Registered User
 
hdflstf's Avatar
 
Join Date: Oct 2007
Location: Desert Southwest
Posts: 540
Re: HELP!! Brakes went out!!

Simple but be sure to bench bleed it to get the air our before you install it.
hdflstf is offline   Reply With Quote
Old 05-28-2008, 11:54 PM   #10
stanglifemike
Registered User
 
stanglifemike's Avatar
 
Join Date: Jan 2008
Location: Carrollton, GA
Posts: 43
Re: HELP!! Brakes went out!!

How do you bench bleed ??
__________________
71 C-10
98 Mustang GT
06 Mustang GT
stanglifemike is offline   Reply With Quote
Old 05-28-2008, 11:56 PM   #11
stanglifemike
Registered User
 
stanglifemike's Avatar
 
Join Date: Jan 2008
Location: Carrollton, GA
Posts: 43
Re: HELP!! Brakes went out!!

By the way, I put new pads and rotors on the front about 10 months/1500 miles ago
__________________
71 C-10
98 Mustang GT
06 Mustang GT
stanglifemike is offline   Reply With Quote
Old 05-29-2008, 12:00 AM   #12
stanglifemike
Registered User
 
stanglifemike's Avatar
 
Join Date: Jan 2008
Location: Carrollton, GA
Posts: 43
Re: HELP!! Brakes went out!!

Quote:
Originally Posted by Longhorn Man View Post
You need to step back and look over the whole system.
Park it on dry pavement if you can.
Check the master clylinder... is it full... on both halfs?
When you top it off (I'm gonna assume 1/2 of it is bone dry) and pump the pedal, do you hear fluid splattering?
Are you seeing any puddles forming?
look on the back side of your tires... are any of them wet?

There's a LOT more to it than calipers up front and a master cylinder, and any guesses with what little info you gave us... is nothing more than a guess.

Your initial problem;

only indicates having a little air in the system. So this new problem, is a new problem.
Back half of MS was almost empty, first thing I did was top it off. No splattering and no puddles forming. No wet tires
__________________
71 C-10
98 Mustang GT
06 Mustang GT
stanglifemike is offline   Reply With Quote
Old 05-29-2008, 12:01 AM   #13
sameyrasmea72
Senior Member
 
sameyrasmea72's Avatar
 
Join Date: Aug 2003
Location: Lubbock, Texas
Posts: 2,443
Re: HELP!! Brakes went out!!

Long shot, but one time I had a simular problem and I changed the MC and it did not help any. It turned out to be just the vac. gromet the goes into the booster.
__________________
72 Cheyenne Super
80 Silverado Blazer 2wd
sameyrasmea72 is offline   Reply With Quote
Old 05-29-2008, 12:09 AM   #14
Longhorn Man
its all about the +6 inches
 
Longhorn Man's Avatar
 
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,693
Re: HELP!! Brakes went out!!

a vac grommet on a booster shouldn't cause the pedal to go to the floor, it should cause a rock hard pedal that is hard to move down at all.

The rear portion of the master cylinder was empty, and there is no evendence of fluid anywhere?
You probably are looking at a bad master cylinder.
but there's bad news here too.
If you have power brakes, then all that fluid went in the booster, where it is now eating the rubber lining of the diaphram. It will end up popping the booster.
You can run it, but I would recomend getting it replaced. I personally lost an engine due to the instant lean condition when my booster popped.
Longhorn Man is offline   Reply With Quote
Old 05-29-2008, 12:22 AM   #15
stanglifemike
Registered User
 
stanglifemike's Avatar
 
Join Date: Jan 2008
Location: Carrollton, GA
Posts: 43
Re: HELP!! Brakes went out!!

thanks for the heads up!!
__________________
71 C-10
98 Mustang GT
06 Mustang GT
stanglifemike is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 04:27 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com