I Just Put A T.C.I. front Crossmember And Disc Brakes On The 54. Bought A Firewall Mount Brake Master Cylinder From Walton Fabrication That Came With A CPP Master Cylinder. Checking The Pressures Out Of The Master With A Gauge Everything Looks Good. But, The Pedal ****s, And It Only Seems To Be Stopping On The Fronts. I've Heard Bad Things About The Master So I'm Getting Ready To Order Another Brand. The One They Sent Is A 1"Bore. Does Anyone Have Any Thoughts AS To WhetHer I Should Stay At 1", Go To A Smaller BOre Size, Or Bigger?. According To Walton This Is A Disc/Drum MasterCylinder..Any Body Got AnY Thoughts????
I've used several CPP masters and have never had a problem. You checked the pressures and said they were good....so it doesn't sound like the master is the problem anyway. It sounds like the combination valve has pushed the plunger all the way to one side since you said it feels like it's only stopping with the fronts. You need to recenter the plunger on the combination valve so you get fluid to the rears again. Posted using the Full Custom H.A.M.B. App!
had this happen on another brand, and all the suppliers could not answer or gave bs answers. i had 2 solutions to fix mine. there is a rod from the mc to booster the adjustment is super critical lots of playing around. end up building a mock up of the mc/booster and pedal on the bench to get the adjustment correct. and also changed the pedal ratio car stops great, pedal feel at best "b+"
When you bled the brakes, did you get good fluid flow from the rears? Are the hoses new? Are the brake lines clean and clear? How did the brakes work before you replaced the fronts and the M/C ?
No Proportion ValveAnd Here's Why. Originally WePlumed In The AdjustableStyle From Wilwood. It Didn'tHelp Anything. So, We Pulled It. I Have Straight Fluid Running When I Bleed The Rear. I Use Clear Houser Because I Like To See What I Have Coming Out. No Brake Booster. Thanks EMS ForYourThoughts Though. The Original Brakes Stopped Great Considering It Was A Drum/Drum Single MasterCylinder. I Think I'm Going To Go With The GM Style Proportioning Valve. Just Reading TXTURBO's Thought Has Me Feeling This Might Be The Problem.. One Thing I Did In Pressure Testing Just ForThe Helluva It. Was Plug Either The Front Or Rear , While Leaving The Opposite On The Gauge And The Pedal Gets Rock Hard. It Does It No Matter Which Side You Plug Or Check. But, When You Hook Front And Rear To The Master You Lose Everything. The Pedal Is Soft Like It Is Currently.
Are you sure the lines (front and rear) are hooked up correctly and not reversed to the MC? If they are then you have the air in the lines. The clue is that when you plug the MC port you get a hard pedal. You need a combination valve for disc/drum setup, not just a front/rear adjustable balance valve, but get the soft pedal fixed 1st. Get some speed bleeders or at least a bleed bottle with a check valve. People swear their can't be air in the system, but the testing says you do unless the f/r lines are backwards. Speed bleeders is what I would try next. Make sure the bleeder on the caliper is at the top and make sure you have adjusted the rear drums correctly before bleeding. A 1" bore with no booster is going make for hard stopping unless you have at least a 6-1 pedal ratio. I would also make sure the pedal to MC piston push rod has 1/8" play in it.
Yeah The Lines Are Hooked Correctly. I EvenTried Switching TheM Just For The Helluva It. I've Ran Almost Two Gallons Of Brake FluiD Through This System. Bleed And Rebleed And Rebleed The MasterCylinder Until I'm Blue In The Face. I Set The Drums Tighter Than I Usually Do Just To Ensure They Were Good. Gravity Bleed, "Pump It Up, To The Floor,Ok, Pump It Again." To No AvaiL On The Pedal Pressure. My Co Car Builder Has Build Three Cars In As Many Years And Is Totally Flustered. I Built A NicE Aluminum Head 406 Hydraulic Roller Motor W/Tremec 5 Speed. Sounds And Runs Great. Just Can'tStopThe Dam Thing.. I'm Gonna Try The GM ProportIoning Valve And Update You Guys. Thanks For Al Of The Input. Any Of You Close To Conroe Texas And Willing To Come Fix This Turd? Lol..Cold Beer And Hot Food To Any Takers. I've Neve, Ever,EveR Had This Much Trouble With Brakes. In HighSchoolThe Guy Helping Me RacedSprint Cars At Big H And Battle GroundsHere In Texas. We Were The Champion 3Years Straight And I WaS The Brake Guy For Him. At 16 I Never Had This Much Head Ache Out Off Brakes..
Make sure you have adjusted the drums brakes as best possible. These older drums are finicky for good brake pedal. Buick, Ford, Olds...does not matter.
Even with poorly-adjusted rear brakes, the pedal will still pump up, unless you have a hydraulic leak somewhere. I would go under the car at night with a flashlight, it seems that leaks show up better this way. From there, I'd look at the free-play in the rod to the master. You may have too much. Bob
I have pretty much the identical set-up on my 54 Bel Air. Mustang II front end with discs up front and drums in the rear. I also have the Walton firewall brake set-up. You have to get a brake booster. If I disconnect the vacuum to my brake booster, my pedal goes to the floor and barely stops my car. Hook the booster back up and it stops solid with no issues. Get a brake booster and it will fix your problem.
Thanks for all of the ideas. I'm still at a lose.. It seems as though it's stopping in the fronts only. The only thing i have yet to try is replacing the rear factory rubber line. I doubt that'll do anything but, I'm going to change it anyways.. What a joke. This is a 4 door car we drive every chance we get. My wife ran 12.8's in it at the drags but we can't figure out how to make it stop.. Next I'll just cut the floor pans out and Flint Stone it.. Changed the master cylinder. Added a GM style proportioning Valve.. No luck.. I've never had a brake problem with any vehicle I've built. I just can't believe this one is giving me a run for my money. It's bad when you're thinking of taking it to a mechanic shop. As far as adding a brake booster. I have no interest in that at all. I think of the 10 cars in our car club (that i can't count at this moment.) No one is running a brake booster.. Posted using the Full Custom H.A.M.B. App!
get rid of the old factory rubber line, this is not good, may not solve todays issue but it is to old
Sounds like you bought all the right parts. First I would check the play on the adjustment rod from the pedal to the m/c than plug the front out put and check the rear out put, there reverse and check the front. with the pedal hooked up see how far the rod is out of the mc, then disconnect the pedal and see if the rod come out farther, something (brake light switch) may be stopping the return of the pedal, now also check to see if you have full stroke of the rod, is the pedal hitting the floor of firewall before you have a full stroke? 'If your using a factory proportioning valve (mine off an s-10) I believe there 2 extra outputs you don't use (abs/brake light switch) you may be plumbed into the wrong port. Are your bleeder screws at the top of the calipers? it is possible to mount them upside down by switching the right and left sides (ask my neighbor) you will always have air in the system. A 1 inch bore is fine a 3/4 ton truck only has a 1 1/8 bore. did you make your pedals or did you get them from waltons, changing the length and pivot point of a brake pedal drastically changes the leverage . Godspeed MrC.
Mr.C i bought the pedal setup from Waltons.. I know I'm coming all of the way off of the master with the stroke but I'm not sure how to determine if I'm going far enough down. The pedal will hit the floor if i mash it there.. The calipers are right side up (breeders at the top.). The Waltons pedal has an extra hole just below the one I'm using. It just puts the rod at a funny angle.. If i plug the front line or rear the pedal gets rock hard. I tried switching the lines on the master cylinder but that didn't change anything. If we get a light rain and I'm on an open road. I can slam on the brakes and the fronts lock up. The rear don't do anything. I've adjusted the rear. Bleed them and when bleeding they'll blow fluid clear to the other side of the car.. As far as the proportioning valve. I have it plumed just like it shows. I used both of the front outs because i was plumed in a way that made it possible.. Someone suggested removing the guts from the valve so the brakes would all be tied together. At this point if you said i should use motor oil/transmission fluid/or water instead of brake fluid. I'd give it a shot. When the car had four wheel drums and a single cylinder master cylinder it had a better pedal than it does now. I put all new **** and that's exactly what i got.. Posted using the Full Custom H.A.M.B. App!
Still no rear.. Great pedal though. Another friend suggested new rear wheel cylinders since these say on the car for close to two years out in the weather unused. That's a cheap replacement but i just haven't done it... Posted using the Full Custom H.A.M.B. App!
You may not need this but I will post it anyway. It's a great reference to double check with. http://www.piratejack.net/index.php?option=com_content&view=article&id=11&Itemid=18
SOP around here, we will never know. Some guys just give up and the car sits. We had one 2013 thread resurface the other day, an update from the OP and he was right where he was 5 years ago...
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