Help with low brakes
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Help with low brakes
Every single vehicle I ever work on ends up with low brakes.. I'm terrible at this.
I bought a 1980 Bronco, it had the firmest brakes Ive ever felt in an older car.. brought it home, did some work to the engine (not even the braking system) and now my brakes are to the floor.
I hear a swoosh when I press the brake, when it finally does firm up the brake lights come on (they dont when I first touch the pedal), is this just a leaking booster? pumping doesn't help.
I don't know where the brake light switch is, it might help troubleshoot considering it doesnt come on until I get the pedal low enough for the brakes to start working. It's just like 3/4 of the travel doesn't do a darn thing at the brakes.
like i said, every older vehicle I have ends up with this issue, even the 95 blazer I just bought started having this problem 2 days after I bought it, and all I did was change the air filter.
I bought a 1980 Bronco, it had the firmest brakes Ive ever felt in an older car.. brought it home, did some work to the engine (not even the braking system) and now my brakes are to the floor.
I hear a swoosh when I press the brake, when it finally does firm up the brake lights come on (they dont when I first touch the pedal), is this just a leaking booster? pumping doesn't help.
I don't know where the brake light switch is, it might help troubleshoot considering it doesnt come on until I get the pedal low enough for the brakes to start working. It's just like 3/4 of the travel doesn't do a darn thing at the brakes.
like i said, every older vehicle I have ends up with this issue, even the 95 blazer I just bought started having this problem 2 days after I bought it, and all I did was change the air filter.
Post Fiend
Joined: Jan 2005
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Well the booster may or may not be bad but it is NOT the cause of excessive pedal travel.
Low brake fluid can be a cause but I assume you have checked that.
The first thing to check is the condition of the rear brake shoes. Pull both drums and have a look at how much wear there is on the linings. If worn replace the shoes and adjust them. If OK then replace drums and adjust the shoes (through the slot in the backplate). There is a good chance that will bring the pedal up.
As for the brake lights I would think there is a pressure switch on one of the brake lines so the lights will not come on until the pedal is hard.
Hope this helps.
Low brake fluid can be a cause but I assume you have checked that.
The first thing to check is the condition of the rear brake shoes. Pull both drums and have a look at how much wear there is on the linings. If worn replace the shoes and adjust them. If OK then replace drums and adjust the shoes (through the slot in the backplate). There is a good chance that will bring the pedal up.
As for the brake lights I would think there is a pressure switch on one of the brake lines so the lights will not come on until the pedal is hard.
Hope this helps.
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It did.. but I ran home, opened up the cylinder and it was empty
it's the front smaller reservoir, which means rear brakes (right?) I cant find a leak anywhere though.. it might be in the rear wheel cylinder..
it's the front smaller reservoir, which means rear brakes (right?) I cant find a leak anywhere though.. it might be in the rear wheel cylinder..
Post Fiend
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You are correct, the smaller resevoir is for the rear brakes. Most likely a leaking wheel cylinder but check the hard line along the frame rail, these can rust out. Check the RABS module (in the hard line along the left frame rail) as these can leak also.
When you find and repair the leak you will have to bleed the system including the RABS module.
When you find and repair the leak you will have to bleed the system including the RABS module.
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I think I found it, a trail of wetness coming down my tire in the rear.
ive been through this before on these old trucks and their brakes.. you fix one thing and something else fails. Before I bought it, they changed out the passenger wheel cylinder, so the driver's side fails.. next will be the rear brake line, then MC, etc etc..
ive been through this before on these old trucks and their brakes.. you fix one thing and something else fails. Before I bought it, they changed out the passenger wheel cylinder, so the driver's side fails.. next will be the rear brake line, then MC, etc etc..
