Brakeline to master cylinder plumbing

[Mheiron]

Hi gang,

Working on a 69 Charger.

Replaced a master cylinder and new front brake lines that were looking iffy.

The brakes are stock front disc / rear drums.

I’ve bled the system 3 times with a quart of brake fluid but still have a soft pedal that will go to the floor. The car stops when the brakes are applied but the pedal is way to soft. There are no leaks anywhere. Hoses looked reasonable but not new.

I think I reversed the front / rear brake lines when they were installed but wanted to check if that seemed like the cause to y’all.

I plumbed the rear line to the smaller front outlet and the front brakes to the larger rear port. I’ve searched around but couldn’t find a definitive answer or if both ports are the same.

Thanks in advance for the help!

 

[dadsbee]

That's the way they go (and lines should only fit one way!).. sounds like you have air in the nose of the master! Did you bench bled it...

 

[Mheiron]

Yes, did the bench bleed

Wonder how to get the air out of the nose?

Remove the master and bench bleed again?

 

[Runner 68]

If you have the time, try gravity bleeding. I'm talking let it set for 3-4 days, crack the rear bleeders and observe the amount of air that comes out. Car needs to be level or at ride height. Let it set for a few more days and repeat the process. Don't touch the brake pedal. Obviously keep the MC topped off and leave the lid loose so the air can escape throughout the process.
Has always worked for me with stubborn brake systems. Bleeding brakes sucks, I don't care who you are.

 

[MarkLevi]

...soft pedal that will go to the floor. The car stops when the brakes are applied...

Did you work on the rear brakes? Excessive shoe-to-drum at-rest clearance can have that effect; the auto-adjusters need to be manually expanded?
Just a thought.

 

[Mheiron]

Yeah, I did adjust the rear expanders to have more drag on the drums.
I’ll have to try gravity bleeding.
Fun to hear someone else thinks bleeding brakes sucks.

 

[Don Frelier]

Any chance the front calipers are swapped?
Bleeder screw needs to be at the highest point.

 

[MarkLevi]

One additional question and a thought:
Were you getting good flow at all bleeders? - to rule out an internal hose collapse. Bleed longest/furthest to shortest/nearest which is typically RR/LR/RF/LF.

If you suspect air in the MC: Using a level, I'd raise the back of the car up on jack stands so the MC piston is dead level during the process. You and your helper need to communicate steps/status clearly so the pedal only moves in the correct direction when it's supposed to. If you're alone, then gravity or, preferably, vacuum bleed. (I always start with gravity anyway to gently fill the system before adding in pressure) That's about all I got

 

[Sixpactogo]

Soft pedal usually equates to air in the system. I did the same as you and had the same issues. Can't remember how many times I bled them before being happy with the pedal. I was using the vacuum pump method but was not having much luck. I finally ended up having my wife run the pedal while I bled them individually before I was happy with them.

 

[Mheiron]

My wife got a chuckle when I told her she was needed in the shop. I think I’ll try that next. I’ve been vacuum bleeding.
Thanks for all the thoughts.

 

[Sixpactogo]

My wife got a chuckle when I told her she was needed in the shop. I think I’ll try that next. I’ve been vacuum bleeding.
Thanks for all the thoughts.

My wife told me it "just needed a woman's touch." Hope it works for you.

 

[Runner 68]

Sure fire way to a divorce, bleeding brakes with the Boss.