Took my car around the block today, and it won't stop for ****. Here's the rundown, 28 roadster, 66 nova rear, 52 chevy drums up front, 68 stang master cylinder. Everything in the entire system is new, and the m/c has equal size resavour front and back. I have real good pedal, but back brakes tend to lock up with alot of pressure applied, and it doesn't feel like the fronts are grabbing much/at all. No residual valves, but everyone with the same set up I have talked to don't run em either, nor proportioning valves. Do I not have em adjusted enuf, need to rebleed the lines, air trapped somewhere, give me ideas.... If ya try to power brake it, even on wet pavement, the car just rolls. Got me stumped.....Fido
well,this wil be a good learning post, do you know if you really have the front res hooked to the front brakes? did it ever work nice?
you've done all the regular stuff, right? like flushing the entire system and starting with new fluid or taking the drums off and wiping them clean (i have had dirt make mine slow to stop) or just taking the shoes off and scrubbing them with some sandpaper to make sure they haven't turned slick or checking your springs, etc to make sure they aren't wore out or if you're tight in the back and loose in the front, check your parking brake cable and connection...
The correct thing is to reduce the size of the rear wheel cylinder bore or increase the bore size on the front,, or both! Adding a proportioning vavle to the rear line will help some, maybe enough to do the trick. If your mastercylinder is mounted on the firewall you most likely will not need residual vavles. Besides you stated you have a good pedal so I don't think adding them will do anything but drain your wallet.
hey man, I just put a 67 stang master in my 57, and I ran into a similar problem. That master cylinder has a built-in proportion valve if I'm not mistaken. The front resovoir goes to the rear brakes and the back resovoir goes to the front brakes...which is sort of ***-backwards in my reasoning at least. I had a good pedal but was locking up the rear tires with the car still moving quick. Also, make sure that your front brakes are adjusted well or else your rear brakes will grab first and prevent any more pressure from going to your front brakes. If you have to pump the pedal and you don't think there is any air in the lines, then bad front adjustment is likely the cause. Best of luck man
the master cylinder is for a drum/drum set-up, mounted in the floor. EVERYTHING from end to end on the brake system is new, with the exception of the drums, which have been freshly turned. It just feels like the fronts aren't working at all, but if you jack it up, they are. I have a very hard pedal....
you have the lines to the front and rear connected to the correct resvoirs right? back to front, front to back
57 joe makes a good point,,,,you have turned the master cylinder around from the way it would be mounted on the mustang,,,,,,,,,,,,,try reversing the lines.
Time is our ememy - has the car sat a while? sounds like a stuck wheel cyl possibly.......pull the rubber boot back on the front wheel cyls and see if there is any corrosion stopping the pistons there. also check for FREE PLAY in the plunger rod going into Master Cylinder.....I even saw a guy had about the same problem on his and it was caused by a plugged brake hard line....it had set on the shelf and was a new home to mud dobbers!
Did you have the front brake linings arced to the drum so they make full contact.You could pull drum off and see if whole shoe is making contact.Gregg
Your "new" M/C may be by-p***ing internally, and only applying even pressure to one end.. Even new parts can be faulty, thats why we get guarantees. Is there a residual pressure valve in both sides of the M/C?