1966 new brakeline system check

[Jef S.]

I just installed new stainless steel brakelines on the 66 project. With the body off its obviously easier to accomplish this which is what i did. My question is, is there any way to check that all the connections are sound before the entire car is re-assembled that is to say with the body still off the frame with no master cylinder connection.

[Greg W.]

Re: 1966 new brakeline system check

Jef, I replaced all mine on a 66 last summer with the body on , so you should be able to get to every thing after the fact. Otherwise with out the master on ,or air pressure I would not know.

[Bob R.]

Re: 1966 new brakeline system check

Stainless can be difficult to get the joints to seal but they should all be exposed after the body drop. I am not a big fan of SS if the old steel lines lasted for 50 years as every day drivers then they should hold up fine the way the cars are driven now and if detected you will take a hit in judging.

[Michael W.]

Re: 1966 new brakeline system check

Brake line pressure can be 1200+ psi during maximum effort stops. With a decent safety factor, I'd want to test at 2000psi.

[Timothy B.]

Re: 1966 new brakeline system check

Stainless can be difficult to get the joints to seal but they should all be exposed after the body drop. I am not a big fan of SS if the old steel lines lasted for 50 years as every day drivers then they should hold up fine the way the cars are driven now and if detected you will take a hit in judging.

I agree with Bob about the steel lines and IMO no problem using them. Without fluid you could plug the lines where the calipers and master cylinder connect and use a miti vac to pull a vacuum to see if it holds.

[Gary B.]

Re: 1966 new brakeline system check

I agree with Bob about the steel lines and IMO no problem using them. Without fluid you could plug the lines where the calipers and master cylinder connect and use a miti vac to pull a vacuum to see if it holds.

Tim,

Even with a good vacuum pump that gets down close to 0 psia, will a pressure differential of 14.7 psi be a good test if operating pressures of 1200 or higher are experienced during real world braking conditions? I fear not.

Gary

[Duke W.]

Re: 1966 new brakeline system check

With flare fitting joints, it's good idea to tighten-loosen at least three times to ensure a leak free seal. The male portion acts as a die that forces the female flare conform to the male when it's tightened, but it may take more than one try. Stainless steel is tougher to seal due to being less ductile than mild steel.

Then test with shop air pressure (100-150 psi) and spray each joint with a soap solution and look for bubbles. If the joints hold air at shop pressure they should hold at the several hundred psi line pressure that hard brake application can generate.

Duke