67 Brakes feel weak.

Hey guys, got a 67 gt with the front Kelsey caliper system, i just replaced the master cylinder and two brake lines that were leaking bad along with the rear portioning valve

(bought the car with brakes not working)


After Bleeding all the breaks, i try them out by and going up and down my drive and they just feel weak, like i cant even purposely lock the brakes up on loose rocks.

Front pads look like their 80% life left and the rear pads look good too, But as far as how old they are is beyond my guess.

What should i start checking/looking at first ?

ty

Bleed them again. Have been some reports of the auto parts store master cyl not working out of the box new. Jeremy Daniels of Facebook just had that problem with a new master cyl on his 67 GT.

Make sure the rear drums are adjusted properly. Also make sure the automatic adjusters are working and installed on the proper side. I don’t know how many times I have found them with broken, stretched or missing cables and / or swapped sides. Apparently there are some real hacks out there working on brakes.

Did you adjust the push rod length when you replaced the master cylinder?

Did you bench bleed the master & use a new gasket when installing it?

Did replace the rear portioning valve entirely or just fix the leak? Regardless i would keep it on the list of things that might be causing the issue.

I fought the brakes on my 67 for years and sounds like exactly the same “weak” brakes problem. After one shop ripped up a major bill after not being able to solve the issue, Cougar Bill redid the system once more and the portioning valve was the problem all along.

Also bench bleeding the master and a power bleed of the system would help to rule out air in the system.

Best of luck!

Sorry for the delay. Work has been busy and havnt had a chance to look at the car. But i started doing what everyone recommended. And then when i got to the rear of the car. BAM. Fluid down the inside rear wheel . The rear wheel cylinder let go. When i first bled it, it held pressure and didnt leak. but i guess a after a day or two i guess it said nope im too old for this.

Ill report back when i get time to change it.


Thank you everyone !