(below: Igor Kessel's homemade pressure brake bleeder) Let me first say that I can't pretend to be an expert on brakes. My car still has stock discs in front and drums in the rear. I have never used anything but basic brake pads. I have never used ATE brake fluid. I don't even have stainless steel/Teflon flexible brake lines yet! But I have repaired my brakes a few times and just succeeded in flushing the fluid, so I will share what little knowledge this experience has forced me to absorb. 1. Brake bleeders. These little suckers break off if you're not careful. Bye bye caliper. Luckily my rear cylinders are generic VW parts and run about $12 each. My search for stainless steel bleeder screws has been fruitless, so what I do now is remove them completely, put some anti-seize on the threads before reinstalling, and then when I'm done and they are retightened, smear anti-seize all over them and replace the little rubber caps. 2. Pressure bleeding/flushing. I borrowed my neighbors pressure bleeder and it was hopeless. With 30-40 PSI in the tank all I got at any given brake was a dribble of fluid. Now I really wanted to flush my fluid - it was an ooky brown color, probably some of it 16 years old. When browsing in Sears I noticed they had a "one man bleeder" for about $5 - just a couple of hoses, a small plastic jar, and some bleeder fittings. This thing makes it so that when you let up on the pedal, no air gets sucked back into the caliper or cylinder. I must say, it works like a charm. I set it in a margarine container to catch the brake fluid pushed all the way out of it and used most of a quart to pump each line until clear fluid came out. You should take care not to splatter brake fluid on any paintwork as it comes out - brake fluid eats paint fast. 3. Squeal. So embarrassing. I have sometimes used gobs of RTV on the back of brake pads, but the last time this didn't help at all. I think the rotors are what actually vibrate anyway. Whether it happens depends on pad composition and geometry. I just put on some pads from a parts car so I don't know what they are, just that they have plenty of meat on them. I didn;t do anything to treat them at all. No squeal. 4. Clean up and "caution". When you handle your brake parts, after taking stuff off your car, you are bound to get oil, grease, dirt, and anti-seize on your pads, rotors, and face. You don't really want this junk on your friction surfaces, so have a can of brake cleaner (duh!) handy to give them a quick wash before you hide them. Your face will just have to suffer. I also use the brake cleaner to spray off the booster if any brake fluid dribbled down it, some usually does. I suspect Igor's suggestion of water would work just as well here.  A. The cap. Took the one from a 5000/100/200 P/S reservoir. It's the same cap as on the brake reservoir. I paid $5 at a junk yard. I took the float out and enlarged thehole to 0.476". Bought two regular rubber tire stems (the narrow ones, there are 2 different designs available). Ran one of the stems trough the 0.476" hole. I also machined an Al ring and knurled it on the outside. I've put this ring over the cap w/ the mil-spec Armstrong A-12 epoxy, so it prevents the plastic cap from expanding under pressure and popping off the reservoir. B. The reservoir. Ordered a 1L chemical jar with a 110mm phenolic rosin screw lid from Edmund Scientific. Drilled two 0.476" holes through the lid, spaced 2" apart. Ran the second tire stem through one hole. Ran a chemical feed-through union through the other. Inserted a 0.25" hard plastic tube into union so that when the lid is screwed onto the jar the bottom tip of the tube touches the bottom of the jar in order to pick up brake fluid from the very bottom of the jar. To the other end of the union I connected a 1.5m Tygon hose with a quick disconnect for a tire stem on it's opposite end. C. Pressure source. Took an old freon tank. Brazed a brass *T* to its valve. On that T installed a quick disconnect nipple for charging it from a regular shop air line, a pressure regulator with a dial gauge and a 1.5m Tygon hose with a quick disconnect for a tire stem. [ed. note: I believe these can also be purchased ready made.] D. Procedure: 1. Fill the car's brake fluid reservoir.
E. Tips: 1. Test drive the bleeding apparatus with water first. A geyser of brake fluid WILL ruin your paint! [ed. note: you better get that stuff dry before you use it!] 2. Keep a bucket of water handy for that inevitable spill off. Should it ever happen to you (the cap pops off, the jar breaks - whatever, FLOOD the sucker with water!!! It is a lot more expensive to repaint the car than to rebleed the spoiled brake fluid. 3. When bleeding the brakes keep the jar in a container. I use an empty 1 gallon olive oil tin. 4. Thoroughly cover the fenders with rags. If you spill brake fluid you'll be glad you did cover them, coz you'll have about 20 sec to salvage your paint after which it's history. 5. Keep an eye on brake fluid level in the jar. If you miss and fill the MC and ABS unit with air, it will require rebleeding of the whole sys over again. No biggie, but it consumes time and brake fluid. 6. Bleed the old fluid into a clear bottle of the same capacity as the jar - it will help you to determine how much fluid is left in the jar without having to crawl from under the car. 7. Bleed the old fluid out through a clear Tygon hose (1/4" or 3/16 I.D. depending on the size of the bleeder screws). It will make bubbles visible. 8. Use only quality brake fluid. I prefer German Pentosin DOT-4. Some people on the (quattro) list swear by ATE Racing Blue. Just don't use any Pep Toys, Quaker Trait and other no-name stuff, they like to ruin seals in the brake system. The only acceptable domestic fluid would be Castrol LMA DOT-4. Igor Kessel
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