DIY brake pressure bleeder

difficulty: 1/5


The recommended method of bleeding the brakes in the VW service manual is to bleed them under pressure.  

You can buy one or you can make your own.  First, always use new parts because you don't want to mix chemicals in the bleeder.  Be careful when working with brake fluid - keep it off the paint because it will quickly eat your paint.  

Here are pictures of what you are making:  It can cost about $50 less than a retail brake bleeder with similar functionality.  These are not professional pressure brake bleeders, nor are the ones you can buy for $100.  Professional pressure brake bleeders use a diaphragm like an air bladder to separate the pressurized air from the brake fluid.  This keeps air and moisture from being mixed with clean fluid.  The tiny bit of air should not make any noticeable difference and is not visible to the naked eye but it's there.   A professional shop machine also needs to hold gallons of fluid for many jobs. Pics and tips mirrored from: and 

For details on how to bleed your brakes, see:
mk3 - 1000q: bleed brakes A3 Jetta, B4 Passat
mk4 - 1000q: bleed brakes A4 Jetta, Golf, New Beetle
mk4 Passat - 1000q: Passat bleed brakes
mk5 VW - 1000q: bleed brakes A5 Jetta

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1 gallon sprayer
Hose Barb Adapter
Pipe Bushing 
10' of 3/8" vinyl clear tubing 
ATE N3030-33314 brake master cylinder cap (pictured below)- fits VW and some other euro cars
small washers and o rings


Take the master cylinder cap and remove the inner cap/seal.  Drill a hole in it and put the hose barb through the hole.


You don't want to crush the o-ring, just snug it on.  Over tightened o-rings are a main cause of twisted and pinched o-rings and leaks.  



Snip off the end of the sprayer wand and clamp the vinyl hose to both ends.  


Optional:  attach a bike valve to use an air compressor for pressurizing the sprayer or to check the pressure.  Recommended pressure is 10-14 psi, anything more could damage the brake master cylinder seals or encourage a loose hose to pop off and spray brake fluid everywhere. 


To use, attach the cap to the brake fluid reservoir and pressurize the bleeder.  Fluid will go through the hose and into the brake fluid reservoir.  Just make sure to not over pressurize the sprayer and to relieve the pressure from the sprayer slowly.  As always, wear safety glasses and follow all precautions in your factory service manual.  Remove any excess fluid in the master cylinder reservoir with a turkey baster when you are done.