The $20 DIY Brake Pressure Bleeder

You've heard me extol the songs of brakes and brake fluid, and how its important to change it every two years. 
I'd like to take credit for this idea, but I got it from this page.: - Here's another one too.

And his idea was good.  But I felt I could do better, for less.  I have a lot of VWs to care for, and one of the pains is bleeding the brakes.  I like pressure bleeders, they do a great job.  This one I made up works super, and it can be built with minimal tools in less then an hour. 

Look, here's the same thing I made for less money.... wow $114.99 LESS!!!

You'll need some basic hand tools and a Dremel with a stone cone-shaped bit or a drill and a set of bits.  I just eyeball stuff when I build.  A wise man told me "Cut Twice, Measure Nunce."

You'll want to use a NEW sprayer tank, don't go grabbing whatever you see in the shed, or was used last summer to kill weeds.  Brake fluid is picky about where it has to live.  Make sure to blow the tank out, and the lines before you use it the first time.

This pressure bleeder will (like all of them) will fill your master cylinder up to the very top.  A way to prevent this from happening is, on the last wheel your bleeding, to close the pressure line on the bleeder with the switch on the handle of the tank, and then vent the pressure in the tank.  Then bleed out the excess fluid VIA the wheel cylinder or caliper.  Or, use a cheap dollar store turkey baster to suck the excess out of the master cylinder.

This little ditty will work wonders for your VW's brakes, or hydraulic clutch on your VR6 or Vanagon.. well, just about any European car! So on with the show...!

Basic Rules, clean brake fluid up with cold water. Keep all fluids, water, dirt, and oil out of the brake system (except for clean brake fluid). Keep brake fluid off all painted surfaces.  If brake fluid comes in contact with paint, wash it off IMMEDIATELY with cold water!

Shopping List: 

With the exception of the brake fluid cap and the tire valve stem, everything can be had at your local Home Depot or quality hardware center.

1 - RL FlowMaster 1 Gallon Sprayer Model 1401HD - $8.00
1 - Watts A-192 1/4"x1/4" MIP Hose Barb Adapter $1.50
1 - Watts A-778 3/8" MIP x 1/4" FIP Pipe Bushing - $1.50
1 - 10' section of Watts 3/8" vinyl clear tubing - $2.50
1 - ATE N3030-33314 Master Cylinder Cap - Found locally $5.00

This was OEM for these cars:
Mercedes Benz 190E 1986 - 1987
Mercedes Benz 280SEc/c 1968 - 1970
Mercedes Benz 300CD 1978 - 1981
Mercedes Benz 450SE 1973 - 1975
Volvo 760 V6 1983 - 1986

Its a 100% perfect direct fit for the VWs (as well as, well just about every BMW, Volvo, Mercedes and so on..).

This cap is great for this project since it does not have the float switch mounted in the center of it.

Stuff I had on hand, so I call it free.

2 - Small washers
2 - Small "O" Rings
1 - Bolt-on style chrome tire valve stem.


The Cap.

This wonderful cap, so expertly designed by ATE labs (pronounced Ah-Tay, its German).. has a small hole in it.  This hole has an interesting story behind it.  All master cylinders have to have some way to allow the fluid level to drop over time.  If not they would create a vacuum and the fluid would cavitate in the system causing it to bubble.  The cap, is a breather vent.  By holding it up to the light, you can see it.  Older domestic cars had a cast iron master cylinder and a flexible membrane that would have fresh air behind it, and keep the brake system 100% moisture free.,  But the ATE design does not work that way, with a plastic brake fluid reservoir you cannot have a large metal clamp like the US designs.  the ATE design was years ahead of its time, being much lighter weight.  Anyhow, enough of the history lesson.




See that, part Watts #A-778 just fits in there.  Pry off the cap.  toss it.

Follow the directions and build the sprayer.  If you get lost at this point, your hopeless.  Might as well go to a Suicide Booth.

Take your Dremel with small average sized cutting stone, cone shaped.  Its like 3/8" of an inch in size. 

Grind hole in cap.  I guessed here.  I'm not an engineer. 
And engineer would overdo this, measure, cut, measure, cut... screw that.
I have brakes to bleed.

Cut away flashing from cut

Take Watts A-192 Hose Barb Adapter, washer, and O ring.

Screw into cap.

Don't crush the O-ring.  Just snug it down.

Screw on the bottom half of the hose bar (A-778).  If needed, use another washer or O-ring here. 
Play around with it. - That's it, its done. 
No glue, RTV, or anything. 
Snug everything down.

Install your clear tubing, install a small hose clamp.

Wire nip off the end of the wand from the Sprayer Kit.  Jamb the hose on the end of it, and then

Now you can use the handle on the sprayer to start/stop the flow of the bleeder at will. 
Best of all with 10' of tubing you can use  this on a lift, or at the back wheel and control the flow, watch the fluid level in the tank.  Nice!

At this point, you could use your bleeder.  But hold on, its going to get even better!

Take apart your Bolt on Tire chrome valve stem.

Dremel a hole (using the same bit you did before) in the side of the tank.  Make sure its not on a seam of the tank.  And make sure its near an area that you can reach your fingers into.

While the plastic is still hot hand tighten in the butt of the valve stem into the tank.  This will create threads.

Remove the stem and blow out the tank with compressed air.  Remove all "flashing" from the tank with a small blade and your fingers.  ya know, rough plastic bits.

Thread the stem in from the inside.  Its tight, but I could do it.  So can you.  Might need a beer at this point.

Pump it up, see how much pressure it can hold.  Cool eh?  Not only can you check the pressure this way, BUT you can FILL it with an air compressor, OR bleed the excess air out of the tank when you are finished!  Sweet!!! (Note: always bleed excess air from the tank before storing it.  This will prolong the life of the seals and reduce the stress on the valves.)

Make sure to test it before you put brake fluid in it.  I just held my thumb over the lower half of the cap and listened for air leaks. 

Most cars are bled at about 20-30 PSI.  Some are as low as 10.  See what works good for you.  Don't EVER push more then say... 50 PSI... you'll rupture the master cylinder.  Keep an eye on the fluid level in the bleeder tank, you don't want it to go dry and push air into the system!  And again, you may wish to add a hose clamp on the end of the line where it meets the cap just as an extra safety measure.

Finished and workin' FINE!