I replaced my old drums with disks on front new lines,hoses,new proportion valve, new calipers and rotors, after bleeding system and mashed the pedal the front brakes lock up, to where the only way to move the wheel is to bear hug it to turn it while off the ground,anyone ever had this problem. Thanks in advanced!!
front disk brakes
- Thread starter dmartin
- Start date
cj69RR
Well-Known Member
Sounds like the master cylinder is not releasing hydraulic pressure for some reason.
69hemibeep
Sponge Bob Square Wheels
Master cylinder. They make them for front disc and rear drum
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Yep sure sounds like a master cylinder to me too. Sometimes if the master cylinder piston hasn't traveled that far in the master cylinder bore the piston will get stuck like when you mashed it.
Here's something that happened to me that had everything to do with the brake rubber flex lines from the body to the brake caliper and why one of the cheapest safety things you can do on an old car is to replace them. I had a little 1972 BMW 2002 that the front left caliper started to stick occasionally and thought that it was just the caliper needing to be rebuilt and I would get to it when I had some time. Well a car pulled off of the shoulder in front of the car in front of me on a wet road in February and we both jumped on the brakes. My front caliper LOCKED UP and spun me into oncoming traffic and some how I was able to avoid a head on and got it back into my lane with the caliper still locked. I clipped the corner of this old crown victory with my driver's door and exploded my left hip into five pieces and still to this day have a pin, plate and nine screws holding it all together. Totaled my car along with the hip and found out the flex line was the issue. I got another car and have since only used braided stainless steel lines or BRAND NEW RUBBER FLEX LINES on all of my vintage cars. Usually the first things that get replace regardless of what they look like on the outside. My '72 2002 BMW was fully restored and in nice shape so I thought life was good........never again will I not replace the flex lines for how cheap they are. I never thought the little drag that was going on would ever cause what happened and I guess the wet road at the time really made the difference. Like your Road Runner right now if it happens with wet conditions it could be bad too so replace that master cylinder and throw on a full set of new O.E flex lines ASAP.
(Wasn't in too bad of shape back in '86 when it happened. Lot's of performance stuff done to the motor with a set of Jere Stahl the Mopar racer headers and a Mallory dual point mechanical advance distributor, suspension and a kick a$$ audio system that was so well hidden it flipped people out.)
Here's something that happened to me that had everything to do with the brake rubber flex lines from the body to the brake caliper and why one of the cheapest safety things you can do on an old car is to replace them. I had a little 1972 BMW 2002 that the front left caliper started to stick occasionally and thought that it was just the caliper needing to be rebuilt and I would get to it when I had some time. Well a car pulled off of the shoulder in front of the car in front of me on a wet road in February and we both jumped on the brakes. My front caliper LOCKED UP and spun me into oncoming traffic and some how I was able to avoid a head on and got it back into my lane with the caliper still locked. I clipped the corner of this old crown victory with my driver's door and exploded my left hip into five pieces and still to this day have a pin, plate and nine screws holding it all together. Totaled my car along with the hip and found out the flex line was the issue. I got another car and have since only used braided stainless steel lines or BRAND NEW RUBBER FLEX LINES on all of my vintage cars. Usually the first things that get replace regardless of what they look like on the outside. My '72 2002 BMW was fully restored and in nice shape so I thought life was good........never again will I not replace the flex lines for how cheap they are. I never thought the little drag that was going on would ever cause what happened and I guess the wet road at the time really made the difference. Like your Road Runner right now if it happens with wet conditions it could be bad too so replace that master cylinder and throw on a full set of new O.E flex lines ASAP.
(Wasn't in too bad of shape back in '86 when it happened. Lot's of performance stuff done to the motor with a set of Jere Stahl the Mopar racer headers and a Mallory dual point mechanical advance distributor, suspension and a kick a$$ audio system that was so well hidden it flipped people out.)
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