If I have new brakes, calibors, lines,and wheel cylinders why is thebrakes still not workingt?

Question

its a 1982 chevy 383 motor 400 transission, 4 barrel carboratot

bleed the lines it work for a block then went out

it was hard at first then becamr mashy and brake lihgt came on

Answer 1

You may have air in the lines or a leak.

Answer 2

Hopefully this will help. Please engine and transmission does not apply here. Is there any brake fluid in the reservoir? Where the brake lines bled properly when all the parts were installed? If someone did them for you at a local shop, call the repair shop for help. If a friend did it, chances are the air was not bled from the system when the new parts were installed.
If you spent all that money on all new parts, you must have spent over $700 easily. New brake calipers are not cheap, rebuilt ones are not cheap as well. New brake lines are not cheap as well.
Another question, what kind of car is it?

Answer 3

Take it to a Chevrolet dealer and request that they "pressure bleed" the braking system. If that doesn't get it the power brake / master cylinder needs a rebuild or replacement. Have you got a a hot rod or something? Where did you find a Turbo Hydro 400 and a bored and stroked 350?

Answer 4

Well whats happening? what are the symptoms? Could be a master cylinder internally leaking, could be an external leak, could be air in the lines. Many possibilities, have it diagnosed by a licensed mechanic and go from there. Hard to say without more information.

EDIT- Sonds like an internally leaking master cylinder, a leak somewhere in the system, or a bad brake booster (though uncommon). Dubble check the work you did, or take it back to the garage you hade the work done at. See if you see anything obviouse, if not, further diagnosis is needed.

Answer 5

That's one of two things. Either the master cylinder or the brake booster loosing vacuum. Easy enough to test the brake booster. Pull the brake booster vacuum line and plug it to the engine. If your petal stays hard when depressing brakes and doesn't go soft as you say in your after comments then you can pretty rule in that being the issue. If its still spongy then master cylinder.

Answer 6

bleed the brakes correctly, startin with the pass. side rear wheel then work ur way to the front endin at the wheel closest to the master cylinder. if that does not work check 4 leaks closely if none r found then i would start thinkin about master cylinder replacement!

Answer 7

Sounds like you still have air in the system. Take small rubber hose and attach to bleeder valve fill small container with brake fluid and put end of hose in container. be sure it stays submerged in the fluid crack bleeder valve and pump brakes till all air is out. Hope this helps

Answer 8

you may have air in the lines, bleeding the system takes care of that. you may also have to adjust the sprocket in the rear drums. after doing that, test the brakes by rolling in reverse and hitting the brakes.

Answer 9

master cylinder or power booster. is pedal mushy, soft, or hard when you press on it?? if pedal is hard its generally the power booster. this is the big round thing that the master cylinder mounts to at the firewall on the driver side. if the pedal is mushy, you may have air in brakes and they need to be bled. have you had your rear brakes checked?

Answer 10

bad master cylinder, air in the brake line

Answer 11

You may have air in the lines bleed your brakes that may help