Hey all, I'm getting around to working on my c3 I inherited from my father. He had a brake fluid leak he could never track down, so I'm doing a full booster/master/brake line replacement. In planning out the work I see the brake lines are between the tub and frame rails, and appear to be bolted down in tight spots. Anyone have any tips on replacing them without lifting the body off the frame?

 

Welcome to the Forum and the world of C3s.

Does it look pretty rusty and corroded down there? Did you look at the inside of the wheels, see any evidence of brake fluid dripping/leaking? Or did you look at the calipers and rubber brake hoses? I would start there rather than the hard lines, those are going to be tricky....

 

We hunted for fluid loss pretty thoroughly, could never find any sign of it, but slowly his brakes would go soft and after one "oh-****" moment where the parking brake saved him, he parked on blocks and that was the end of it. I've rebuilt all calipers and replaced flexible lines. He had a knack for buying cheap Chinese parts because chrome is shiny 🤦‍♂️, I'm sure there was some boiling off or something happening. The lines look good, but they're likely nearly 50 years old, it's just a matter of time. I've been building track cars since I was 10, safety equipment is at the top of the list of things I won't slack on. The lines are probably fine, and if a body lift is the only way to do them, they can stay a while longer. 🤷‍♂️

 

On a couple by the drivers door I had to cut the clip, pull the brake down to get a wrench on the bolt. I don't think I put a new clip back on, not really needed.

 

Can the dripping also be from the calipers? That was the first thing I noticed on mine. Based on that I just assumed it is the calipers. Obviously I could easily be wrong. When I am going to replace the calipers I was gonna replace the rubber brake hoses and pads as well.

 

The lines look good, there is 0 evidence of any leak, other than the level dropping at the master. My dad was just topping it off when he drove it, but after an o-**** moment where he was only able to use the e-brake to stop, he put it on blocks and never got around to figuring it out before he passed. He liked chrome and put a bunch of Chinese cheap parts on it, including the booster and master cylinder.

I'm not an expert by any means, but I've been building track cars with my family for 3 decades, and safety gear is at the top of the list of things I refuse to go cheap on, so I rebuilt all of the calipers, got stainless lines and braided flex lines, and improved OEM booster/master. I assume he was either boiling off cheap fluid and the vapors were leaking from a poorly fitting cap or some other gremlin, but I'm not about to take chances. I guess I can just cut the clips as was mentioned and maybe use a band and some fabric to keep the lines from rubbing due to vibration.

Other than boiling off, I have no idea where the fluid would be going, there is some evidence of an oil drip inside the drivers side firewall/floor, but in a 50 year old car, it could be anything.

 

i think worst case, if it came down to pulling the body, i would cut the lines and leave em there and run new ones tucked into the corner between body and frame as close to orig lines as i can get them.

 

Mysterious zero brake pedal moments can be produced by cheap rotors with poor run out. It can pump air into the caliper(s) while cruising and leave you with a pedal on floor WTF situation. Vettes are full of surprises.

Good luck

 

I would look everything over again. if the fluid level is going down in the master cylinder it has to be going somewhere and should be leaving some kind of sign. did you loosen the MC from the booster to see if it's leaking out the back of the MC? I would keep looking till i found it if possible. it would not hurt to put new rubber lines on all four corners if they are old but if the hard lines look good leave them. my hard lines are 51 years old and still in decent shape.

 

you can replace the long brake line from the front to the back by snaking it from the rear up to the front with out pulling the body. I used stainless steel and was able to do it from underneath by slightly straightening the factory bend that goes to the master cylinder then re-bending it