AJV69 2 Report post Posted May 9, 2018 The power brakes on my 69 Mach 1 auto are overly sensitive and brake very easily and quickly. Just finishing up resto work and installed a rebuilt Midland booster, new brake lines, new master cylinder, and cleaned up and reused proportioning valve that was on car. Any adjustments that I am missing? Quote Share this post Link to post Share on other sites
JET 445 43 Report post Posted May 9, 2018 Have you got the correct pedal?, power brake pedal is different to manual brake pedal and mounts in a different hole. Quote Share this post Link to post Share on other sites
LoneWolf2U 136 Report post Posted May 9, 2018 Most overlooked adjustment is booster rod to master cylinder plunger depth. From your post I would expect to find it is too long and making brakes touchy. I would also check to insure that they are fully releasing after pressing the brake petal, My guess is they are dragging slightly. Quote Share this post Link to post Share on other sites
1969_Mach1 333 Report post Posted May 9, 2018 The only time I have seen an over sensitive brake pedal was when something was wrong with the brake booster. First, is it the correct booster? 1969 was the year Ford switched from Midland to Bendix. Some early 1969's still got the Midland booster. They do interchange without any modifications. From what I understand, the Midland booster provides greater power assist but was unreliable compared to the Bendix booster. *** Before you condemn the booster, follow Mach1Rider's and Jett 445's suggestion and make certain everything is correct. 2 Bob & Sue and TheRktmn reacted to this Quote Share this post Link to post Share on other sites
Midlife 814 Report post Posted May 9, 2018 You sure you're not driving a GM vehicle? 1 RPM reacted to this Quote Share this post Link to post Share on other sites
Johns Summer of 69 14 Report post Posted May 9, 2018 2 hours ago, 1969_Mach1 said: The only time I have seen an over sensitive brake pedal was when something was wrong with the brake booster. First, is it the correct booster? 1969 was the year Ford switched from Midland to Bendix. Some early 1969's still got the Midland booster. They do interchange without any modifications. From what I understand, the Midland booster provides greater power assist but was unreliable compared to the Bendix booster. *** Before you condemn the booster, follow Mach1Rider's and Jett 445's suggestion and make certain everything is correct. I agree. I would have to say this would be my first area to look into. Here is a great video talking about Cougar/Mustang brake boosters - Quote Share this post Link to post Share on other sites
buening 63 Report post Posted May 11, 2018 Does the car tend to nosedive when you apply the brakes? I had a sensitive brake issue before and it turned out to be a leak in the rear brake line, causing only the front brakes to work. Quote Share this post Link to post Share on other sites
fvike 173 Report post Posted May 18, 2018 I think a manual brakes MC (small bore) paired with an booster can make for sensitive brakes. Quote Share this post Link to post Share on other sites
