Brakes Brake opinions

OneWheelPeel

Active Member
Dec 23, 2015
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What’s up everyone.
I haven’t posted in a long time and have been slowly restoring my fox while daily driving it. The brake booster is giving out now and it’s time to be replaced. The pedal has been a little spongy lately and I noticed on a hill today that I lose pressure while holding the car stopped and I have to reset the pedal or press harder to get the required pressure.
So with that being said, I don’t plan on adding bigger brakes or doing any kind of conversions for a few years if ever. I have an all stock set up. Do y’all think it’s worth it to put a cobra booster and master cylinder on with the stock brakes? Or should I just stay stock?

Thanks.
 
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Wayne Waldrep

Before I post a pic, do you have one of yours?
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Mine did something similar once and it ended up being the check valve. Have you checked that? That sounds strange. :D
 

OneWheelPeel

Active Member
Dec 23, 2015
249
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North Carolina
It really sounds like the master cylinder is going bad to me.
Forgot to mention I was going to replace the booster and the master cylinder just to be sure. I don’t play around when it comes to brakes after I had a booster go out on me on the road. But anyways, I got the booster now and once I track down the master cylinder I’ll replace them and post an update.
 
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OneWheelPeel

Active Member
Dec 23, 2015
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North Carolina
So I got the new master cylinder and boaster in. I bled everything and then realized the pedal was still only getting pressure in the lower portion of the movement. I researched and found out I made the scrub mistake of not measuring the booster rod... I’m assuming that is my problem because I can play with the pedal and my assistant says the brake fluid doesn’t move until more than halfway down the pedal movement.

So my question now... do y’all think I could get this rod adjusted with out disconnecting the lines again?
 

Mustang5L5

i'm familiar with penetration
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Yup, just carefully bend it forward. It will go.

You may want to siphon off some fluid from the MC if it’s topped off
 

OneWheelPeel

Active Member
Dec 23, 2015
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North Carolina
Update: I can’t seem to get the brakes bled out..
so I opted to not bench bleed and just bleed the whole system out while on the car. I did this and got fresh fluid on all bleeders. After that I still did not have enough brake pressure and that’s when I realized I should adjust the booster rod.
So I did that and it still didn’t feel right. I decided I was tired of messing with it and was willing to have a shop bleed them for me with a pressure bleeding. Did this and they were way better but I could still put the pedal to the floor and not lock the wheels up. The brakes weren’t building pressure or getting hard even though it was able to stop itself.
So I figured I just needed to adjust the rod at home since the brakes were bled. But now even with the rod maxed out I still can’t get the pedal to not go to the floor and brake correctly.

Before I take it back to the shop or trade this car for a new motorcycle what do you guys think?
 

Mustang5L5

i'm familiar with penetration
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If you didn’t bench bleed the MC, the angle it’s mounted at traps air at the front.

Either jack the rear up so it’s level and hope all the air gets purged, or bench bleed it
 

OneWheelPeel

Active Member
Dec 23, 2015
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If you didn’t bench bleed the MC, the angle it’s mounted at traps air at the front.

Either jack the rear up so it’s level and hope all the air gets purged, or bench bleed it

Do you think that even after the shop pressure bled the system there would still be air in the master cylinder?
 

General karthief

wonder how much it would cost to ship you a pair
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Even a pressure bleed will not get that bubble trapped in the top corner.
It kills me when someone says 'if I can't (insert whatever here) I gonna sell/burn/drive it off a cliff. I know most don't mean it.
i fought bucking, whistling and it sounded like a sewing machine at idle, the only time it felt strong was over 3k rpms. The rest of the time it was a fight just to get it to move. That was over a period of 2 years!
It's just a car and it can be fixed.
 

OneWheelPeel

Active Member
Dec 23, 2015
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North Carolina
Update: brakes are a lot better now after the master cylinder was bled but still feel weak and can get the pedal to the floor. Next is to replace these rotors. They are pretty bad with a lot of heat cracking so hopefully I see a big improvement with the new ones.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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I feel replacing the rotors will not resolve your issue, if they are stress cracked then replace them but it likely will not change how the peddle feels. You still have air in the brake system. JMO
 
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Mustang5L5

i'm familiar with penetration
Mod Dude
Feb 18, 2001
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Massachusetts
Update: brakes are a lot better now after the master cylinder was bled but still feel weak and can get the pedal to the floor. Next is to replace these rotors. They are pretty bad with a lot of heat cracking so hopefully I see a big improvement with the new ones.


With the car off, pump the pedal a few times. Does it get hard as a rock with virtually zero travel?

If not, you still have air in the lines
 

OneWheelPeel

Active Member
Dec 23, 2015
249
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North Carolina
Yes it does get hard with the car off. The pedal feels strange right now when the car is on.
It’s super soft but the car brakes fine. The only problem is how “light” it feels and it goes to the floor. It’s hard to describe but it doesn’t have the same air feeling that I’ve had before.
I’ve had a shop pressure bleed it three times now and bench bleed the master cylinder now so I’m going to see how new pads and rotors do.