Author Topic: Brake pedal isn't as "stiff" as it was, and there is a hiss....  (Read 3454 times)

Offline Scatterbrain

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Brake pedal isn't as "stiff" as it was, and there is a hiss....
« on: September 09, 2008 - 12:26:54 PM »
I haven't driven my Chally in almost 2 weeks and today decided I'd let her out.  Right away I noticed the brake pedal was different.  It still stops and everything, but where there used to be a "cushion of air" (for lack of a better description) between me and the actual engagement of the brakes there is nothing.  It doesn't feel as hard as manual brakes, but almost.  When I engage the pedal there is a definite hiss coming from under the dash.  I popped the hood in the parking lot and engaged the brake and there is no hiss on that side of the firewall, definitely coming from under the dash.  I turned off the engine and engaged the brake, it was stiff at first, but eventually softened with another slower hiss.  I'm thinking a seal went out on the brake booster or the booster is going by-by.  Anybody else have any thoughts? 




Offline wally426ci

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Re: Brake pedal isn't as "stiff" as it was, and there is a hiss....
« Reply #1 on: September 09, 2008 - 12:28:01 PM »
sounds like the booster to me...  :dunno:
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Offline ChallengerHK

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Re: Brake pedal isn't as "stiff" as it was, and there is a hiss....
« Reply #2 on: September 09, 2008 - 02:09:38 PM »
 :iagree: That's what I was thinking.


"She'll make point five past light speed. She may not look like much, but she's got it where it counts, and I've made a lot of special modifications myself."

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Offline MEK-Dangerfield

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Re: Brake pedal isn't as "stiff" as it was, and there is a hiss....
« Reply #3 on: September 09, 2008 - 05:42:47 PM »
I guess you have power brakes?   :dunno:

No hiss with manuals.   :lol:   :lol2:


  Mike

Mike

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Offline ChallengerHK

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Re: Brake pedal isn't as "stiff" as it was, and there is a hiss....
« Reply #4 on: September 09, 2008 - 06:20:25 PM »
I guess you have power brakes?   :dunno:

No hiss with manuals.   :lol:   :lol2:


Or if there is, then you really have problems  :roflsmiley:


"She'll make point five past light speed. She may not look like much, but she's got it where it counts, and I've made a lot of special modifications myself."

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Offline Scatterbrain

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Re: Brake pedal isn't as "stiff" as it was, and there is a hiss....
« Reply #5 on: September 10, 2008 - 10:12:56 AM »
I guess I have manual brakes now.   :roflsmiley:

sigh, I hate changing out brake boosters....

Offline ksierens

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Re: Brake pedal isn't as "stiff" as it was, and there is a hiss....
« Reply #6 on: September 10, 2008 - 11:19:06 AM »
As we get older, nothing seems to be as "stiff" as it used to be.  :naughty:
1970 Triple Black Challenger R/T  440 Six Pack - 4 Speed - 3.55 Dana
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Offline Bullitt-

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Re: Brake pedal isn't as "stiff" as it was, and there is a hiss....
« Reply #7 on: September 10, 2008 - 12:11:32 PM »
As we get older, nothing seems to be as "stiff" as it used to be.  :naughty:



BOO  HISSS......never had any problems in this area but the check valve would be easier to replace than a booster
http://www.napaonline.com/MasterPages/NOLMaster.aspx?PageId=470&LineCode=UP&PartNumber=89021&Description=Power+Brake+Booster+Check+Valve
Wade  73 Rallye 340..'77 Millennium Falcon...13 R/T Classic   Huntsville, AL
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Offline hooD

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Re: Brake pedal isn't as "stiff" as it was, and there is a hiss....
« Reply #8 on: September 14, 2008 - 12:42:51 AM »
Scatterbrain.....Dude, I have the same problem with my Cuda.  It is the vacuum booster, or at least that's what I thought, but bullitt99 has an excellent suggestion that I hadn't even thought about.  It sure would be easier and a lot less exspensive if it were just the check valve.  Thanks bullit!  I'm going to check it out.
-Larry
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http://www.youtube.com/watch?v=NvrWiLgDm7Y

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Offline hooD

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Re: Brake pedal isn't as "stiff" as it was, and there is a hiss....
« Reply #9 on: September 14, 2008 - 12:44:57 AM »
By the way, if it is the vacuum booster, I strongly suggest that you also replace the master cylinder at the same time. 

« Last Edit: September 16, 2008 - 01:56:01 AM by hooD »
-Larry
member since AUG 2007
http://www.youtube.com/watch?v=NvrWiLgDm7Y

southeastern michigan usa
             
 
            
1973 'CUDA 340
 
original owner
37,117 miles
  
:grinyes: *click my E-Body* :grinyes:

Offline Scatterbrain

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Re: Brake pedal isn't as "stiff" as it was, and there is a hiss....
« Reply #10 on: September 15, 2008 - 11:04:39 AM »
Thanks.  I'll get a check valve and swap it out first.  As for the booster, its actually cheaper to get the master cylinder / booster combo at most places. 

Offline wally426ci

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Re: Brake pedal isn't as "stiff" as it was, and there is a hiss....
« Reply #11 on: September 20, 2008 - 03:56:21 PM »
I heard a guy at Carlisle saying they stopped providing parts for the clamp style boosters. you may only end up with the crimped version. I did, but i dont really care, it works. And i painted it gold.
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      '68 D100

Offline Scatterbrain

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Re: Brake pedal isn't as "stiff" as it was, and there is a hiss....
« Reply #12 on: September 24, 2008 - 02:48:49 PM »
Its nice to have that stiff feeling again <insert your favorite penis joke here>

Turns out it wasn't even the check valve.  I pulled it and the gasket was cracked and worn.  I simply replaced the gasket and it worked just fine.  Time to  :burnout:

Offline Bullitt-

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Re: Brake pedal isn't as "stiff" as it was, and there is a hiss....
« Reply #13 on: September 24, 2008 - 02:51:46 PM »
Great news....which gasket?
Wade  73 Rallye 340..'77 Millennium Falcon...13 R/T Classic   Huntsville, AL
Screwed by Photobucket!

Offline hooD

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Re: Brake pedal isn't as "stiff" as it was, and there is a hiss....
« Reply #14 on: September 25, 2008 - 02:41:10 AM »
Turns out it wasn't even the check valve.  I pulled it and the gasket was cracked and worn.  I simply replaced the gasket and it worked just fine.

What did ya pull, and which gasket, and where did you get the gasket from?    :feedback:  Did you take any pictures? 
« Last Edit: September 25, 2008 - 02:44:02 AM by hooD »
-Larry
member since AUG 2007
http://www.youtube.com/watch?v=NvrWiLgDm7Y

southeastern michigan usa
             
 
            
1973 'CUDA 340
 
original owner
37,117 miles
  
:grinyes: *click my E-Body* :grinyes: