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Brakes Master cylinder reservoir leak

  • Thread starter Thread starter flashback87
  • Start date Start date Jul 20, 2019

flashback87

Member
May 18, 2010
345
4
19
Cleveland, OH
Jul 20, 2019
#1
  • Jul 20, 2019
  • #1
My brakes aren't the greatest so I've been looking into them and doing some research. About 1-2 times a year I have to add a little brake fluid to the reservoir. So I started looking around the master cylinder and noticed what looks like some fluid build up/residue where the mc connects to the booster.

I've also notice the reservoir attached to the mc is kind of loose and wiggles a little. Is this normal? I'm thinking this is causing the leak because the rear of the mc by the booster under the reservoir is a little damp.

Could this be causing my poor pedal pressure? Do I need a new mc or is there a way I can reattach the reservoir to make it seal better?

Dont know if this is related to but there is a pretty loud air sound when I push the brake pedal.

I also attached a pic of the residue where the mc attaches to the booster.

Thanks!
 

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General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,924
10,569
203
polk county florida
Jul 20, 2019
#2
  • Jul 20, 2019
  • #2
I would replace both the mc and the booster.
 
Reactions: JD1964

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,255
17,939
224
Massachusetts
Jul 21, 2019
#3
  • Jul 21, 2019
  • #3
Agree. MC rod seal is probably leaking. When they leak, the rubber destroys the booster.

If you look under the MC there's probably s little rusted, bubbled trail leading down.

Replace both
 
Reactions: JD1964

flashback87

Member
May 18, 2010
345
4
19
Cleveland, OH
Jul 21, 2019
#4
  • Jul 21, 2019
  • #4
Thanks! I'll move forward with both.

Are the typical car parts stores replacement mc and boosters acceptable?

I just have the stock discs in front and drums in rear.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,255
17,939
224
Massachusetts
Jul 21, 2019
#5
  • Jul 21, 2019
  • #5
Yes. Oem replacements from your typical rebuilders like raybestos will be fine
 
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