They sell thousands of those $6 things, 'cause they are worthless and not even worth the effort to return them. I recently tried 2 different types and went back to my own setup. The nylon hoses that come with those kits don't stretch well and maintain a good grip on the bleeder valves. I even just tried the one with the freakin' magnet that doesn't work either.
I've always had to improvise and use what I have available at home (I only had 1 car at the time. So I had to learn to get things done/fixed, when going back to the auto parts store was not an option, because the car is torn apart some way).
Best part is that it's usually free and you end up with a container that you can use to keep/dispose of the old fluid. This has worked for me WAY-BETTER than any of the gadgets.
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What you will need:
1. Large empty brake fluid bottle
2. ~2 feet of vacuum line/hose (inner diameter I.D. should fit your valves)
3. Small box end wrench to open/close valves
4. Fresh, new brake fluid (small or large bottle)
What you do with it:
Basically, just get the empty plastic container (LARGE empty brake fluid bottle is perfect). Get a piece of rubber vacuum hose which fits the valves you are working with. Punch a hole into the cap of the bottle and feed the hose thru, 'til it gets to the bottom.
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Put enough CLEAN brake fluid in there so that air can't get sucked back in thru the hose and put the cap/lid back on with hose going to bottom of bottle.
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Make sure that the hose is long enough and set the bottle down near the caliper/hub you are working with 1st. Rule of thumb is to start from the furthest away from the master cylinder 1st. TIP: Just in case ('cause the small cheap ones fall over and leak), I place a few shop towels around the bottle, just to make sure it does not tip over. Open the cap/lid slightly, so that the bottle is able to vent the air in/out.
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Make sure the reservoir is full. If you're just trying to get air out of the lines to decrease sponginess, you can use the small bottle. If you have dark, old fluid, you may want to take this oppty to use the large bottle and pump out all of the old stuff. Begin by using a turkeybaster (or whatever) to suck out as much of the old stuff out of the reservoir. Fill back up with some of the new, clear fluid (you'll be glad if you do this anyways). In that scenario, you may have to drain out some of the old fluid from the receiving container to make sure it doesn't overfill. You can be anal and replace the bottle with another at some point and do it all over again, 'til all you get is very clear fluid in and out. I did this to replace my old DOT3 black fluid with a newer Synthetic (Valvoline Syntech, I think).
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Loosen the valve slighty. Tighten back slightly and then place the wrench on in a way, where you can just turn slighty to open and close the valve.
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Place the hose on to it and push it on 'til it can't go no more. I usually push it until it reaches the wrench and holds it in place.
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Open the valve and go pump the brake a few time and them hold down all the way once, for a few seconds.
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Go back and tighten the valve, refill reservoir, and repeat for the remaining valves.
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I am actually doing this today, to replace the valves with some speedbleeders for the wife's MKIV. I'll take some pics and maybe update this as a write-up... It takes the same amount of time to bleed the brakes as any other time and I've done a better job than with any of the gadgets. I spent ~$30 last Summer trying a few the `$6-$10 kits. They just look kewl, don't work right, and after you're done, a pain to store.