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It means you have leak in one side of your brake system and it is moving the shuttle valve and actuating the brake warning light. It may be you have air in one side that is compressing a bit and allowing it to move slightly too. Inspect your brake hydraulics and it would behoove you to bleed them too. Stu
 

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Discussion Starter · #3 ·
Thanks.. well i have the car up on stands and i had one person step on the brake while in drive and I kno for sure that one wheel kept moving... not sure about the other one....
 

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air in the system causes a pressure differential on the system. Time to bleed the brakes completely.
 

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Discussion Starter · #6 ·
alright.. weather is better now and im back to working on the car.. jus to restate my problem again.... car was in storage since the late 70's early 80's. After we got it into running condition i drove it. It has power brakes... but when i drove it brakes were bad.. def didnt feel like power brakes.. needed alot of foot pressure to slow down the car and braking distance was horrible. Brake light in the gauges is on.

I changed the master cylinder and booster to a universal one. I had to modify the attachment to make it work. I changed the brake cylinders on the rear drums and new rotors and pads in the front. Small improvement in the brakes but very minimal and def still not what power brakes shuld be like. Please help I dont know what it could be.

Should I get the factory booster/cylinder rebuilt instead of universal?
Not enuf vacuum?? but i have a mild cam
manifold where sensor is and all the lines connect to is bad?
 

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Discussion Starter · #8 ·
yes i bled them from the brakes themselves.. never ran a whole bottle of brake fluid thru tho. never bench bled either.

I dont kno if it makes a difference but the brakes arent spongy like most weak brakes r. Instead the brake pedal barely moves at all. Takes alot of foot pressure to stop the car and i have to pull the pedal back up with my foot when im done braking to raise it so i can brake again next time.
 

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I'm no expert but it sounds like to me that the pedal or mechanical nature of the application sounds bad.... thats just me though, so don't quote me! I'm a noob with these old cars.
 

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Discussion Starter · #10 ·
u culd be right. when i took off the old booster and master cylinder the pedal moved in the range it should but when hooked up to the new booster and MC the pedal has a very stiff restricted movement span of about 1 inch.
 

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Discussion Starter · #12 ·
im guessing ur mean where the pedal attaches to the booster/MC.

I was planning on changing the lines and get a new distribution block..
-from MC to distribution block to front brakes
-from MC to proportioning valve(bypass distr. block) to the rear brakes
 

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Why did you use a "Universal" booster and master? That's just asking for trouble, man.

Also, without bench bleeding the master, you will have air in there. Period.

Of course, if you have a pressure bleeder, there is no need to bench bleed, but........

Greg
 

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if your car is like mine, check the top of your distribution block. there should be a two-wire electrical plug. disconnecting this should cause the light to go out. inside that distribution block there is a shuttle valve. what happens is when one side (front or back) loses pressure, as in bleeding, the shuttle valves moves and grounds out the switch causeing the dash light to come on. it was supposed to be a "hey, you need to look at your barke system" light. you can have someone hold pressure then crack the lines at the block and the light should go out. it's either front or rear. you maybe able to move it by taking the switch out and using a small pointed object to move front or rear. if that doesn't work you may have to dissassemble the block, clean everything then start all over. mine was stuck in one position for so long I couldn't get the shuttle valve out so i just pulled the plug. now I am in the process of going all Wilwood.
 

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Discussion Starter · #16 ·
thanks alot... I did have hesitations about getting a universal booster and MC and I was considering getting my old one rebuilt. Now hearing what you guys said I will def ship it off to get rebuilt and take the universal one out.

I did notice the electrical plug on the top of the dist. block. I pulled it temporarily so the light would go away. I remember trying to break the lines loose at the block and they wudnt budge with regular open end wrenches. I recently got those brake line/fuel line wrenches that wrap further around the nut. I will try breaking em loose with the new wrenches and taking the switch out.

If I cannout get the lines out of the block can I get one of these aftermarket dist blocks?

http://www.hotrodsusa.com/store/product2346.html

In a nutshell I suppose I should get the original booster/MC rebuilt and rebuild/replace the dist block. Hopefully this will solve the prob.
 

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I'd stick to stock style replacement parts. It sounds like that proportioning valve is stuck and you aren't getting all of the air out. It also sounds like you may have a booster problem. Was your old booster bad, or did you replace it due to its age.? After running the engine turn it off. Remove the check valve from the grommet on the booster and make sure you hear vacuum bleed off. You got lucky to have power disc brakes, I believe those were special order with a small block.
 

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Discussion Starter · #18 ·
Brakes were weak to begin with... so i threw in the universal booster/MC. Took the car for a drive and the brakes felt worse if not the same. This makes sense according to what your saying. Its most likely the proportioning valve in the dist. block. Any by puttin in the universal boosteer/MC I jus made the prob worse.

I will check for the vacuum... Thanks!!!
 

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Discussion Starter · #19 ·
An update... I got my factory booster rebuilt and slapped that on the car. Bled the system at each wheel individually. I didn't bench bleed. The pedal travel is exactly how it should be, however brake pressure is bad and the pedal goes all the way to the floor. To get the car to stop I have to pump the brake pedal a couple times and then I have enough pressure to stop the car. The car will not stop if the brakes arent pumped right before stopping.

<font size=-1>[ This Message was edited by: yankee81116 on 6/8/07 9:26am ]</font>

<font size=-1>[ This Message was edited by: yankee81116 on 6/8/07 9:16pm ]</font>
 
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