pinexcorp 1 Report post Posted August 4, 2021 Midlife.. You got it exactly right. Once I connect the break lines and system is bled brakes feel like a sponge and finally stop the car about 1" from the floor. In my original question I forgot to mention that the two front brake hoses were also replaced at the same time the MC was replaced. As mentioned the car running and braking perfectly.. almost to good to be true. Rear brake and other rubber hoses are ok . Front disk and rear shoes are well adjusted. A real puzzler I have been working on cars 50 yrs and never been puzzled by a problem.. My next step is to replace the booster just to take it out of the equation although I don't think that is my problem. Quote Share this post Link to post Share on other sites
pinexcorp 1 Report post Posted August 4, 2021 Midlife.. You got it exactly right. Once I connect the break lines and system is bled brakes feel like a sponge and finally stop the car about 1" from the floor. In my original question I forgot to mention that the two front brake hoses were also replaced at the same time the MC was replaced. As mentioned the car running and braking perfectly.. almost to good to be true. Rear brake and other rubber hoses are ok . Front disk and rear... Quote Share this post Link to post Share on other sites
jjstang 51 Report post Posted August 4, 2021 I too have a 69 mach1 with stock power disc. I experienced the same issue after I replaced EVERYTHING the last time. I’ve read other posts for power disc cars that were experiencing the same. Much focus is on the proportion & distribution block valves. Since the brakes worked before the rebuild, I never paid them much attention. Mine were pretty gummed up even though the system bled beautifully. I rebuilt those as well. That took care of the problem. Quote Share this post Link to post Share on other sites
Brian Conway 264 Report post Posted August 4, 2021 Ooops. Brian Quote Share this post Link to post Share on other sites
pinexcorp 1 Report post Posted August 5, 2021 UREKA!! Problem solved. Thank you guys. The push rod coming out of the booster was too short, adjusted an additional 1" and car now stops on a dime. It only took me one weeks and bunch of new gray hair to figure it out, and with the help of everyone here. Thank you. 1969-Mach1 had it right.. So I think the orinal problem had to do with incompatible booster/MC and good think to keep in mind when replacing MC to match and I think the difference is in the push rod. The price on the Mustang just went up. Not gonna burn it. Robert 1 Mach1 Driver reacted to this Quote Share this post Link to post Share on other sites
danno 128 Report post Posted August 6, 2021 On 2/13/2017 at 12:36 PM, MN69Grande said: The pedal is original to the car. Do you mean the hookup on the back of the booster? My car has the original booster and factory power brakes. I could stop by some day and let you drive it to see how terrible they were right out of the factory. I kind of remember where you live. For my car, the pedal feels firm. Stopping is good, but not great. I cannot lock up the front wheels in a panic stop. I think that is typical of the factory system. I am working on a change to different brake system this fall. Quote Share this post Link to post Share on other sites
danno 128 Report post Posted August 6, 2021 3 hours ago, pinexcorp said: UREKA!! Problem solved. Thank you guys. The push rod coming out of the booster was too short, adjusted an additional 1" and car now stops on a dime. It only took me one weeks and bunch of new gray hair to figure it out, and with the help of everyone here. Thank you. 1969-Mach1 had it right.. So I think the orinal problem had to do with incompatible booster/MC and good think to keep in mind when replacing MC to match and I think the difference is in the push rod. The price on the Mustang just went up. Not gonna burn it. Robert Robert, you said you have the factory power disc brakes in you car, and they now seem to work great. I also have them, but I cannot lock up the front wheels in a panic stop. Can you? Quote Share this post Link to post Share on other sites