My car has some sort if 4 wheel disk brake kit. What would cause the brakes to barely work when cold, and drag when hot?
My car has some sort if 4 wheel disk brake kit. What would cause the brakes to barely work when cold, and drag when hot?
Last edited by Devryn; 07-03-2021 at 01:09 PM.
you always have "drag" on disc`s, but i don`t know, sounds strange.
They're heating up and you can smell it.
Need more info. Do you have a power brake booster? What master cylinder? Do you have a proportioning valve?
My initial off the wall suspicion is that you have the master cylinder preloaded. This can provide both your symptoms. Preload prevents full bleeding of the system, which could be your weak brakes. When the system warms up, then the preload causes brake drag.
Come back with the answers to the questions and maybe it can be narrowed down.
Thanks, Rick. I wish I knew more about brakes, but I can identify parts. Looks like this master cylinder with a booster behind it https://www.summitracing.com/parts/clp-m-c118sac and it does have a proportioning valve.
Well...3d printed the tool for adjusting the push rod from the master cylinder to the brake booster. Took the master cylinder off and there's a rubber boot between the two and it's totally crunched, pinched, creased and split...
The boot...
Attachment 11974Attachment 11974
Would the boot cause the issue I'm having?
There should not be a boot between the master and brake booster as there is no room for it as your crumpled up one shows. Get the adjustment between the master cylinder and booster correct and see what it does. There should be just a bit of clearance between the booster push rod and the master cylinder when everything is at rest.