Just completed the install of CPP front disc brakes with booster on my "54" 3100 everything is located in the original location on the frame. I bench bled the master cylinder and than bled all the brakes but could not get a hard pedal. I than removed the master cylinder and bench bled it a second time just in case and I installed residual check valves on the porprtioning valve in case I was getting any bleed back, I than bled the brakes again still a soft pedal, if I pump the pedal a couple of times it gets firm. I am at a loss as what to try next any ideas are welcome. Could the master cylinder be bad, bad proportioning valve how do I know if I have a faulty part or just operator error??? Thanks Mike
Re:&%$^*&$! There is still air in the system somewhere. One of my personal tricks is to fill the master cylinder,go to each wheel cylinder,open the bleeder screw and let the fluid run out until it runs clear. Check the MC after each wheel and make SURE it doesn't go dry. I figured this out one day when I had no one to help me pump the brakes. Good luck!
federale would this trick still work if my master cyclinder is mounted on the frame lower than the bleeders? Thanks
Stupid question Are you bleeding with the engine running, you know brake pedal will be softer with a servo than previous set up
The Stick Trick Sometimes soft pedal is cuased by too much clearance between the pads & rotors or shoes & drums , never assume they're self adjusted . Failing that , if you jamb the brake pedal down with a stick for 24 ~ 48 hours , you'll often get a nice , high rock hard pedal ....
I had a similar experience when I replaced my original single master cylinder with a dual. I bled several times and lived with double pumping to stop while ocassionally rebleeding, adjusting, etc. Finally someone on here (wish I could remember and give credit) suggested that perhaps I had not adjusted the rod that fits in the end of the master cylinder so that it was long enough to give the proper amount of push on the first brake pump. I adjusted it the rod out ever so slightly and solved the problem. Give it a try as you go through your troubleshooting and let me know how it goes. Bill
Bill are you refering to the rod that goes from the pedal to the booster or the rod from the booster to the master cyclinder? Mike
Mine are not power assisted but, on power assisted, it would be the rod from the booster to the master cylinder. Sorry I did not make that clear. Bill
Also check the heim joint that connects the pedal lever to the master. You can fine tune where your pedal actuates the brakes, but make shure you don't have too much drag, as it will heat up the fluid and lock the brakes......ask me how I know.
Re: Hmmmmmm,I dunno. Mine is mounted up on the firewall............ It worked for me on Volkswagens too. The MC is right at the floorboards on them.
when you pump the pedal to bleed the system.How fast are you pumping the pedal? If you pump too fast you airate the brake fluid which puts air bubbles back in the system. Slow and steady is the way to go.If you have access to a pressure bleeder that is the best way to go .Do you have the calipers installed bleeders up ? If bleeders are down that is incorrect and they need to be switched . I have the cpp disc barke conversion with vaccum assist in my 57 and have had no problems in bleeding the system. Bobby
