Another Brake Problem

[aiyana7.3]

Hi all! So here is a little history on my brakes and their problems: Initially, the pedal was spongy and you could press it down all the way when the truck was off. Then, I adjusted the back ones and found a leaking wheel cylinder, fixed that, and then they were working great. Just recently I was working on the truck on something unrelated, started it, and the abs and the brake and park light were on and the brake fluid was about halfway so it had lost some. Also, when the truck was off I could hear a hissing noise so I knew there was a vacuum leak somewhere. So I found a hole in one of the rubber seals that connects the vacuum lines and the brake booster but I fixed that with jb weld and put more fluid in and then it was great.

a week later when I turn it on the fluid is low. I just found a leak on the old hose clamp, but my question is why is my brake fluid getting low when I have leaks in the vacuum system? I'm pretty sure I don't have a leak in the brake system especially because when I push the pedal down when it is off the pedal stops firmly. I looked at the back of the wheel cylinders and the calipers and anywhere else that there is a brake line connection and I cant see a leak. Thanks!

 

[ah1988ford]

The hydraulic brake system and vaccume system are completly seprate. You have a leak in the hydraulic system some where. If I read your post right you said you found some brake fluid some where on/in the vaccume system. That would mean your master cylinder is propably leaking. Check where the master cylinder bolts to the booster for leaks. I reccomend unbolting the master cylinder and check for leaks, you dont need to remove it completley just enough where you can look down in the master cylinders bore and check for fluid leaks.
Tires plus, firestone and most auto repair places have a free brake inspection and if you can drive it up there they can/will tell you what they THINK it is for free and you can then go home and fix whatever the problem was they found if you think its whats wrong. JM2C... its what im going to do I am tired of guessing with mine.

 

[fordf350man]

The hydraulic brake system and vaccume system are completly seprate. You have a leak in the hydraulic system some where. If I read your post right you said you found some brake fluid some where on/in the vaccume system. That would mean your master cylinder is propably leaking. Check where the master cylinder bolts to the booster for leaks. I reccomend unbolting the master cylinder and check for leaks, you dont need to remove it completley just enough where you can look down in the master cylinders bore and check for fluid leaks.
Tires plus, firestone and most auto repair places have a free brake inspection and if you can drive it up there they can/will tell you what they THINK it is for free and you can then go home and fix whatever the problem was they found if you think its whats wrong. JM2C... its what im going to do I am tired of guessing with mine.

i agree, check there for a leak, but once you get all the leaks fixed and you know its not leaking, if you see the fluid level get low DON'T add brake fluid, the brake system is a sealed system and it is also the wear indicator for your brake pads and shoes, when the fluid level gets low then the friction material on the pads or shoes are getting low, when you get to the minimum mark that means its probably time to check and replace them if needed, allot of people add brake fluid and then when they do changed there pads and push the piston back in the calipers they get fluid spilling out of the reservoir, that's because you aren't suppose to add to it, don't know if you knew this or not and not trying to step on anyone's tows, just trying to let you know if you didn't know to avoid a mess later on

 

[franklin2]

i agree, check there for a leak, but once you get all the leaks fixed and you know its not leaking, if you see the fluid level get low DON'T add brake fluid, the brake system is a sealed system and it is also the wear indicator for your brake pads and shoes, when the fluid level gets low then the friction material on the pads or shoes are getting low, when you get to the minimum mark that means its probably time to check and replace them if needed, allot of people add brake fluid and then when they do changed there pads and push the piston back in the calipers they get fluid spilling out of the reservoir, that's because you aren't suppose to add to it, don't know if you knew this or not and not trying to step on anyone's tows, just trying to let you know if you didn't know to avoid a mess later on

Lower fluid level because of shoe and pad wear happens over a long long time. If your fluid level is getting low within a few weeks, you do have a leak somewhere. Make sure you do check the brake fluid level regularly and top it off till you find the leak.

When putting new pads and shoes on any vehicle, the standard procedure now is NOT to squeeze the pistons back in the calipers and the wheel cylinders with the bleeders closed. You always open the bleeders when doing this. Why? I had a mechanic tell me that pushing all that old fluid backwards up the system on the newer cars with ABS can and does cause failures of the valves and other parts of the ABS system. So they don't do it the old way anymore, they always open the bleeders to prevent the old fluid from going back up in the brake components.

 

[fordf350man]

Lower fluid level because of shoe and pad wear happens over a long long time. If your fluid level is getting low within a few weeks, you do have a leak somewhere. Make sure you do check the brake fluid level regularly and top it off till you find the leak.

When putting new pads and shoes on any vehicle, the standard procedure now is NOT to squeeze the pistons back in the calipers and the wheel cylinders with the bleeders closed. You always open the bleeders when doing this. Why? I had a mechanic tell me that pushing all that old fluid backwards up the system on the newer cars with ABS can and does cause failures of the valves and other parts of the ABS system. So they don't do it the old way anymore, they always open the bleeders to prevent the old fluid from going back up in the brake components.

never heard of that, opening the brake system allows for moisture to enter the system, should never be opened unless fluid is needed because of a leak or a flush has been done or it can get contaminated, i was a mechanic myself, pushing fluid back through the system will not hurt anything, they actually sell brake bleeders that back flow from the calipers to the master cylinder, if fluid flows through the system it will also flow back when the pressure is released so no matter what is it is going to flow back through the system

 

[aiyana7.3]

Is there an easy way to find a hydraulic leak? I looked on top of the calipers, on the back of the wheel cylinders, and everywhere else where I can see a connection, but I can't see it leaking...

 

[79jasper]

Could be leaking at the pushrod end of the master cylinder.
Which will travel into the booster.



Sent from my iPhone using Tapatalk

 

[fordf350man]

what he said ^^

 

[icanfixall]

Anytime you shut down the engine. and then try to push the brake peddle your going to find a hard peddle. You have lost the vacuum assist to the brake peddle so its going to be hard to press. Many tight systems will give you one press of the peddle when the engine is off. So wont because the vacuum leaks down.