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Old 05-29-2011, 09:23 AM
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anderkart anderkart is offline
Join Date: Apr 2009
Location: Surprise Arizona USA
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You need to try power-bleeding. Automotive mechanics use expensive power bleeder tools all the time especially with stubborn brake systems that just refuse to bleed out using the old 'pump the pedal' method.

You can make your own power bleeder for free. First get one of those nipple/caps like quart bottles of gear lube come with:

Cut just the very tip off the cap and screw it on your plastic bottle of brake fluid, then slightly tighten a hose clamp around the caps threaded area to make sure the cap seals and stays on.

My karts master cylinders have a round 3/8" hole in the cap used for filling. I just tip the brake fluid bottle upside down, stick it in that filler hole and slightly push/turn it in to make a seal. Then I loosen my calipers bleeders and start squeezing the bottle. This instantly flows brake fluid through the entire system forcing all the air out within seconds. Then while still slightly squeezing the bottle, (so you dont draw air back in) re-tighten your bleeders and voila your done. Brakes bled!

If your master cylinders cap does not have a small round hole like mine, there's a second power-bleeding option that works just as well: You simply power bleed from the other direction at the bleeder screw...

Use the same nipple-cap trick on your plastic brake fluid bottle, but this time find a length of new/clear hose that will tightly fit and slide onto both the caps nipple and also onto the outer nipple that most bleeder screws have.

(you can insert a pair of needle nose pliers in 1 end of this clear hose and pull the pliers handles apart to stretch/enlarge if necessary to make the hose larger and fit your bottles nipple. slightly heating this clear tubing with a flame will allow it to stretch even further)

If your brake bleeder doesn't have a nipple you can just remove the bleeder screw and stick the brake fluid bottles nipple right in the hole and squeeze.

Be sure to remove the master cylinders cap first so there wont be an air-lock and also so you can see when all the air has been forced out of the system.

One way or the other, you should be able to figure some way to power-bleed your brake system. You dont need (or want) to pump the pedal at all while power-bleeding.