Hi all. My 69 with power drum brakes has been sitting for a long time. I went to move it and as soon as I apply any pressure to the brake pedal the front wheels want to lock up. Master cylinder is full of fluid. Has my master cylinder gone bad? Opinions? Thanks
Do you have any leaks in the back brake lines? Also it could be the proportioner valve (maybe also called an equalizer?) Could be just from sitting. How much have you tried to use them?
No leaks in the rear. I have driven around the block but thats it. It doesn't pull to either side, just locks up instantly. Should I try driving more, maybe free it up? Where should I start to trouble shoot? Thanks
Were you storing it in an enclosed area and, if so, was it on concrete? A whole lot of moisture comes up from concrete and, if not covered, has probably rusted something. Could be drums...
Mark
68 Firebird 350 auto (sold) 70 Trans Am RAIII 400 4-speed (sold) 2011 Challenger SRT8 IE392 6-speed (sold) 2017 Challenger Hellcat 1966 Dodge Coronet 440
There is nothing to discuss as to what the problem is, and this is where you need to sart: a complete hydralic system rebuild. The booster and lines may be okay, but the master cylinder and wheel cylinders need to be replaced. You will experaince a catostrophic brake failure if you continue to drive the car.
Master cylinder and wheel cylinders are somewhere in the $150 raneg, with some possible change leftover. Rust in the drums can be knocked out with coarse sandpaper and the crud can be buffed off the shoes. I installed new shoes even though they still showed 80% because I couldn't see putting old shoes back on. (By the way, it sounds as if the booster has failed, so that might be on the list too. But you can still stop the car with a faulty booster. It 'dont work that way with hydralic failure.)
Forget collision damage costs, or worse, have you priced what it cost to repair a paint chip? You'll find a brake overhaul one of the cheapest things you can to for the car, and it's the very first thing that needs to be done. Cardinal rule #1: The car must stop.
Rust in the drums can cause this. Instead of your shoes sliding to a stop they grab right away on the rusty drum inside surface. Take the front drums off and if they are rusty inside clean them up with sand paper. Put them back on and if it still does it I'm with Merv, rebuild. Something that many people neglect with there classic cars is the brake fluid. Every few years it should be completely replaced. Totally bled out. If you don't you are going to need to rebuild the system.