<ul><li><a href="http://www.bmw-m.net/TechProc/bleeder.htm">click</a></li></ul>

<ul><li><a href="http://www.audiworld.com/tech/misc24.shtml">http://www.audiworld.com/tech/misc24.shtml</a</li></ul>

Sounds to me like you need to start with at least a quart of brake fluid in the sprayer. Over time, won't that fluid pick up moisture? Especially since you're subjecting it to increased pressure, which will force more moisture into the brake fluid.

When all is said and done, I don't know how much the homemade version really saves compared to the essentially identical $50 <a href="http://www.motiveproducts.com/frame-bleeders.htm">Motive</a> "European Power Bleeder" that I use.

<img src="http://www.motiveproducts.com/images/smbleeder3.JPG">

You raise a good point about air pressure forcing moisture into the brake fluid. I believe commercial power bleeder's have a bladder seperating the air and brake fluid. I don't follow the "standard procedure" of putting brake fluid in the bleeder. Instead I only add brake fluid to the car's brake fluid reservoir. I don't think this helps the moisture issue, and you can only bleed one caliper before needing a refill, but it makes clean-up a heck of a lot easier.

Also, the pressure guage on the bleeder is a must. Much more than 10 psi and you risk cracking the car's brake fluid reservoir ... one major mess.

I think your suggestion of not filling the sprayer with brake fluid makes sense. I would be most concerned about the sprayer sitting around half-full of brake fluid between uses. Lots of opportunity to pick up water and other contaminants.

Pressurizing a full brake fluid reservoir would probably not drive that much moisture into the fluid.

http://tinyurl.com/4q8gp<ul><li><a href="http://tinyurl.com/4q8gp">brake bleeder from JC Whitney</a></li></ul>

Quote from JC site of Vacuum tester tool: Fast…with little possibility of trapped air entering lines already bled.
If You want problems - This tool is prime choice.

This is a vacuum only tester. You could use it to remove old fluid from master first - before power bleeding brake. With clean fluid prior to bleeding.

But appling only vacuumm to the brake system at bleeder with out first having a power bleeder attached first is lookibg for trouble.

I just gave You a trade secrete - sorry.
The best power bleed You can perform is having both pressure at Master - and a vacuumm tank at bleeder. When the bleeder is cracked loose -
The violent pulse of fluid will scrub the system. Finish off with pressure only - then seal it.

Ambient air is always with moisture unless your in Palm Desert California.
This is why You change fluid every August - and is why only the lower half of all brake systems are corroded when left to do so.

1. Add brake fluid to the Motive Power Brake Bleeder tank.

2. Firmly connect the supplied adapter to brake master cylinder and pump the Motive Power Brake Bleeder to pressurize.

3. Starting with the furthest away brake bleeder valve (typically on the rear of the vehicle), open brake bleeder valve and purge the air and old brake fluid from your brake system.

For more info visit: http://www.buybrakes.com/motive

Correct. Pretty much once you open brake fluid - use it up.

Then clean it - i use water and then dry it well, but i'm never happy. I'll try alcohol as suggested.

I always put the fluid int eh motive - this makes it much easier and prevents you from ever pushing air into the system,. which is very bad news indeed.

I do this many, many times a year since i track my car. It works.

Vacuum bleeders are, IMO, the devil. They threaten to pull air into the system. A pressure fed system simply can't - its pressurized.

G

i dont agree - and i found out the hard way. many Audi reservoirs are very, very small and have multiple tiny reservoirs internally. You may well run dry. It will be hard to get the air out, and if, god help you, you get it in the ABS, things get worse still.

You dont need to worry about leaving the fluid int he container because you wont. Throw it away. If you are only bleeding, put a pint in. Changing fluid, put in a litre. Even an open can is absorbing water, though.

G

that is a very good point. But does it really matter in an hour or so?

Maybe yes, do you know?

Note: for simple bleeding i just use air int he motive. For flush, i put the quart of fluid in. Once used, its toast IMO.

G

If you have a source of dry, regulated air in your garage, you can simply purchase the threaded 45mm cap and be done with it. You have to ensure you don't let the brake fluid run low and top off as you move from caliper to caliper.

The 45mm caps can be found at your local auto parts store (plastic) for a few bux or you can get a nice one made of Al for ~$35.