I've been working on cars, trucks and motorcycles for many years but this problem is driving me crazy! I bought an unfinished (But drive-able) project 41' Willys off eBay 1 year ago, it sits on an S-10 chassis. The small-block was new and it had a TH350 that I switched over to a 700 R4. The (Under floor power brakes worked but were low so I installed a 2 lb. residual valve in the front line and a 10 lb. in the rear for the S-10 drum brakes, the brakes worked fine after that. Fast forward 8 months, I decided to install a Ford 9" rear-end that I had (Because I'll install an odd-ball big-block engine in the future). The 9" rear-end has drum brakes so while apart I decided to buy the disc brake conversion from Summit...I also installed a 2 lb. residual valve to replace the 10 lb, and an adjustable proportioning valve. I was back to where I started when I bought the car, low pedal! I thought I had a bad residual valve so I changed it, no difference, I replaced the master cylinder, nothing. The brake system had all 3/16" lines so I replace those lines feeding out of the master cylinder to the front & rear "T's", using 1/4" brake line (Leaving 3/16" going to the F & R wheels). Instead of using an adapter off the master cylinder I replaced the master cylinder with a 1980 Corvette (Larger bore which would bolt directly to the new 1/4" lines), I also re-plumbed the lines where there would be no "High" spots to trap air. Today I will be removing the rear calipers and temporarily positioning then so the bleeder screws will be "Up top", to bleed-out any air, then I'll mount them. If that doesn't work I can only think of finding a place that does "Power bleeding". I've done this kind of work on a few under floor brake systems (Hot-Rods), and NEVER had this many problems! PS: The pedal is higher when the car isn't running, but when it is the power brake diaphragm (Looks like a kit from an aftermarket supplier) is feed engine vacuum, it's low but the brakes do lock (I only tried them while on jackstands). >>>> Any one else had this problem?!
I would have done the caliper "Re-position bleed" in the beginning but there was solid fluid (Not one bubble) when I bled them (Running and someone inside pumping the brakes or using my hand-held vacuum tool).
If the bleeder is not up, then air can get trapped, and it won't make any bubbles, but it will still not work right. Another cause of low pedal is the brakes not adjusted properly, which is usually not a problem with disk brakes, unless they have a built in parking brake mechanism. Yet another possibility is the master cylinder being too small bore size, but that's probably not what's happening here.
I agree with Bonzo. We had the same issue on a ChumpCar that we built that had the bleeder screws due to the cobbled together design. Regardless, it will not bleed correctly until those screws are up.
Bleeder has to be the up top to bleed. Sometimes it doesn't work out for mounting so well. Move the a caliper off the bracket, use a piece of wood to sub as the rotor and bleed the caliper. Remount the caliper and off you go.
You might get by for now by removing the caliper for bleeding but think about a future breakdown somewhere West of East Jesus, Nebraska at night on a dirt road in the rain. It will happen if you trrow it together now.
--------------------------------------------------------------------------------------------------------- WTF? Run with just the front brakes?... You need to stop smoking that :STUFF!"
I positioned the caliper (Temporarily) to put the bleeder screw on top all 4 calipers... better but still not right! Sell it !
as I see this this always happens on 4-wheel disc setups. I don't fault somebody for wanting the best system possible BUT is it really necessary on 2500-3000lb hot rod we have done a lot these have been done with drums. that being said I think most of these problems come with the under floor universial corvette m/c just my thoughts. Tom
You may be correct but the price for a new rear Disc setup was cheaper than buying a new Drum setup, plus used stuff in good shape is hard to find in my area of Florida. I went to buy a driveshaft for another vehicle last year, the "Junkie" wanted about the same price as having one made-up!
I have to join the bleeder-on-bottom camp too. Better on top, but the real sucky-fucky is those 4 piston shits with 8 bleeders front and 8 rear and a Chinese hand shake process to bleed em. Here's a better one. Had good brakes, no issues, did the 16 bleeder dance, finally all good. Drag the Asian Stew rod home after Autorama and it sat in the rig overnight, temp dropped to like 34 degrees. Go to get it out of the trailer the next morning and ZERO BRAKES!! A just finished 5 year prison sentence! Don't think 2 assholes weren't puckered up enough to form diamonds, they were! Full credit to my associate Luke for the quick reactions and moves he needed to save the day. He pumped the shit out of it and got brakes when it was rolling down the ramp steering for safety the whole time. Fast forward to nitro pill avoided, check everything, hard pedal, good brakes, no leaks, no air, just a big fat case of the what-the-fucks. That was Feb, bitch still has good brakes! I hope it doesn't fail one day but everything's right. I may have bored a few to tears with all that chin music, but some things just tend to deliver an unwanted rectal exam. Considering the number of import parts that fill speed merchant shelves it's become "normal" that experienced folk like yourself and us at my place will simply suffer the spoils of their profit margins. I hope it sorts out but a power bleed or vacuum may be the only way.The fact it's better having bled them off the car is a tell, no? Maybe? No way to have the bleeders up, huh? All the best... FWIW, the car I mentioned is yellow too. Scary thought...(!)
I remember the time that I took a car (That I just bought) off the a car carrier, there was no brakes! The person delivering it to me said that there were brakes when he loaded it (This car had a firewall mounted master cylinder and clean fluid). I also remember the words "Jap Junk", however, the Japs have improved 95%! It's the F**king Chinese crap out there that's absolutely AWFUL! I'm not talking only auto stuff either, I spent a lot of money on a pair of "Red Wing" boots, the bottoms wore out in 6 months! When I looked for the box they came in to return them I noticed the words "Made in China!" Last but no least... Did you know that we buy large quantities of fish from China? Did you also know that China BREEDS it's fish in their Sewers?
As much as I love seafood, I won't order it at any restaurant. When we buy seafood we look for the "farm raised" label. That means it is bred in s**t. I know this is off topic, but it's just another example of the stuff from China.
I hate yellow, seems that I've bought a few cars already painted that color (Suede Black will be the Willy's color when I have time), same for 3 houses I've owned... That I repainted white!
OK, problem solved! After having only "Partial" success putting the bleeders temporarily at the top, I went to A/Zone and bought two plastic containers of brake fluid. I had an old electric fuel pump hanging around from a Throttle Body Injected El Camino, so I adapted a smaller hose to the rear brake bleeder and then had my Ole' lady feed the master cylinder with fluid while I was sucking it out at the other end. I did both rear brakes and the pedal is fine now (I actually used 2-1/2 containers, luckily I had 1 extra on hand)!
Having the same issue with a '54 Kaiser I've just rebuilt with 4 wheel discs. Rear calipers have the mechanical e-brakes and the bleeders not at the top. Been months trying to get a firm pedal and I've pushed and pulled the fluid in both directions. Even swallowed my pride and hired a mobile mechanic who couldn't fix it but took my $$. Contemplating having it towed to a non-franchise local brake shop. Sometimes it takes someone who knows more... and stopping is more important than going, IMHO.
------------------------------------------------------------------------------------------------------------------------------------------------ Hey Tom, after removing the Calipers one at a time I was able to bleed the brakes by placing a piece of wood between the pads and holding the caliper so that the bleeder screw at the highest point of the caliper, then my wife pumped the brake pedal so I could bleed it. A friend of mine had the same problem with his car and bought an inexpensive Brake bleeder from Summit Racing. You do know that if your pedal is under the floorboards you must have 2 residual valves (For front and rear) and they are different for Disc & drum brakes... Good luck!
Thanks! In my rebuild, I put in swinging pedals and used a (Strange) dual m/c from Jegs, mounted on a reinforced firewall. Thinking I was doing everything right... Guess I need to try the block of wood thing again!
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