Hey guys. I recently got my 71 running after 15 years in a garage, but my breaks are non existent. The peddle is super soft, stiffens up a bit when it’s not running, but as soon as you start it the peddle is like a sponge. The brake boost is connected to the back of the carb, which has steady suction when detached.

Any tips or advise for checking the function of the brake boost or master cylinder? I’m one tiny step away from getting this thing on the road for some exercise.

Thanks.

 

Did you check your fluid and bleed your brakes? Also check for any leaks...after sitting for 15 yrs you prob have some bad seals. Oh, and check the seals on your master cylinder...

 

After sitting for 15 years, you need to check everything about the brake system. I wouldn't assume the problem is the booster. The first thing I would do is check each wheel and make sure there are no fluid leaks at the wheel cylinders. After this much time, that is most certainly a possibility. Once that's taken care of, check for fluid leaks everywhere else.

Have you checked the brake fluid reservoir? Assuming it was filled and that the brakes were working fine when the car was parked, it would be interesting to know if the reservoir is still filled. If it is not, you do have a leak somewhere.

It would probably behoove you to drain and replace the brake fluid, anyway. It is hygroscopic (absorbs water), and, after sitting so long, it would be safe to assume that it has absorbed some water.

In short, you want to go through the system from end to end. I don't think it's quite correct to say that you are "one tiny step" away from getting the car on the road.

Have you checked everything else that should be checked on a car that's been sitting so long? The engine runs. Great. But what about, for example, the cooling system? Power steering fluid, if the car has it? Condition of the tires? Etc.?

 

If the pedal is not hard, its not the booster. I would do an inspection, flush, and bleed.

 

I've got the exact same gig going on with my 79 Hurst Olds right at the moment & I agree 100% with all of the above. I've put about 2000 miles on this car since I got it 2 years ago and I've noticed the brake pedal has gone soft and low on me. I don't do brakes so it's off to the shop for a thorough review. I'm suspicious I have a leak somewhere and I'm reasonably sure (based on the equal amount of rust on the master and the booster) that I may have the original master cylinder on the car. I'm taking (via trailer) this car to Hershey next week and then on to South Carolina where it will spend the winter.

Originality is one thing but I take heed that safety rules over everything else. I'm actually trailering the car first to Maryland and then driving it back to Hershey. If I get into a fatal accident due to my knowing the brakes were faulty, my wife will kill me. She's really looking forward to the South Carolina leg of the journey. I don't want to let her down.

 

Turned out to be nothing much more than a flush and replacing a few seals. Nice.

 

Jaunty questioned the cooling system because anti-freeze absorbs carbon dioxide from the air, which makes it corrosive. That's why our old-style anti-freeze needs to be changed every five years.

There's a lot maintenance that has been deferred in those 15 years of non-operation. Look in your owner's manual or think through your car's systems and get those delayed actions brought up to date before you start driving it.