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how to bleed brakes

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Old 03-01-2012 | 12:40 AM
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Default how to bleed brakes

i replaced the rear pads not long ago. i had no pedal at first but it eventually got firm. then tonight i lost the pedal again, went for the brakes and pushed the pedal all the way to the floor. you can pump it up and get pressure, just doesnt hold. ive been smelling the rear brakes since i changed the pads.
Old 03-01-2012 | 02:14 AM
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easiest way to bleed brakes is get a friend to pump the brakes up and hold them while you crack the bleeders open and repeat until there's a solid stream of fluid coming out. make sure you don't have any leaks anywhere though because just changing pads shouldn't require bleeding as the fluid is just pushed back through the system towards the master cylinder when you press the calipers back in...the air in the system had to get there some how
Old 03-01-2012 | 03:07 AM
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i thought because of the abs module that you couldnt bleed them traditionally. when i was installing gthe pads, i put a c clamp on the caliper and couldnt get it to compress any(yes i had the cap off). so i cracked the bleeder at the calipers to sompress the pistons.
Old 03-01-2012 | 03:21 AM
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Here's what you do, since you don't have a Tech2 to cycle the ABS pump motor while you bleed.

Fill the master cylinder, and pressure bleed the brakes like always, in this order. Right rear, left rear, right front, left front. Then take a short test drive over 15 mph, and brake hard enough to make the ABS engage during braking. ABS all the way to the stop. Do that 3 times in a row, then return to your shop/garage/carport/driveway/whatever.

Refill the master cylinder again, and pressure bleed the brakes again, in the same order.

If your brakes are still spongy, go do the ABS stops again, and bleed the brakes again. I've never seen one need to be bled more then 3 times total, start to finish. Remember to keep checking the master cylinder, and never let it get too low on fluid.
Old 03-01-2012 | 03:55 AM
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ill try that, thanks
Old 03-01-2012 | 04:08 AM
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Don't tell anybody, it's a trade secret.
Old 03-01-2012 | 12:10 PM
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I would use the method as mentioned by AKlowrider.. You can bleed the brakes normally like people have done for years but you cant bleed/flush the abs module unless you have a tech2, or do an abs stop like mentioned above.
Old 03-01-2012 | 01:43 PM
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Pretty sure some mud or wet grass would be easier to work with than asphalt to engage the ABS

But that is good to know.
Old 03-01-2012 | 02:33 PM
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I use the gravel parking lot, or the gravel road, next to the shop. Unless it's winter, then I just use the ice that's everywhere.
Old 03-01-2012 | 02:40 PM
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Originally Posted by AKlowriderZ71
Here's what you do, since you don't have a Tech2 to cycle the ABS pump motor while you bleed.

Fill the master cylinder, and pressure bleed the brakes like always, in this order. Right rear, left rear, right front, left front. Then take a short test drive over 15 mph, and brake hard enough to make the ABS engage during braking. ABS all the way to the stop. Do that 3 times in a row, then return to your shop/garage/carport/driveway/whatever.

Refill the master cylinder again, and pressure bleed the brakes again, in the same order.

If your brakes are still spongy, go do the ABS stops again, and bleed the brakes again. I've never seen one need to be bled more then 3 times total, start to finish. Remember to keep checking the master cylinder, and never let it get too low on fluid.
This is the only way to do it without a Tech 2. Changed pads on my work truck and someone came in the shop and dropped something on my caliper (punctured a piston) and didn't tell me... sucked all kinds of air into the brake system. Read that it gets stuck in the ABS module and only the Tech 2 could bleed them. Figured that I could do it doing this and it worked.



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