maintenance
BLEEDING THE BRAKES & CLUTCH
The tools and materials needed are: 
• 1 Liter can of ATE Gold or Super Racing Blue 
  Brake Fluid
• Power Bleeder (we do not recommend vacuum 
  bleeders)
• Overflow collection bottle and clear tubes
• 11 mm open-end wrench
• Car lift,or hydraulic jack and set of sturdy stands
• Wheel Lug Wrench (and security socket if used)
• Flexible light source to work in wheel wells 
• Paper towels or rags for quick pick up of spills
• Piece of 2”x 4” lumber or an assistant for clutch bleeding

There are two terms that sometimes are used synonymously, but which are not: Bleeding and Flushing the Brakes.
Bleeding the brakes is a quick procedure to remove any unwanted air bubbles from the calipers and lines.
Flushing the Brakes refers to replacing the entire fluids,

The factory recommends Flushing every two years regardless of use.
Why you ask?
Brake fluid is very hygroscopic, meaning that it absorbs water.  It will absorb water from the ambient through the flexible brake lines and through the plastic walls of the fluid reservoir. Brake fluid boils at around 400°F while water boils at 212°F, so once water gets to the calipers it will boil and release water vapor bubbles, which contrary to liquid will now allow for compression, altering the effectiveness of the brakes.

A quick bleed is fine at the track, between sessions, but I personally flush my brakes right before each and every track day.  Also, once you open a new can of brake fluid you need to use it or it will go bad.

I like alternating the brake fluid color every time I flush the system.  This makes it very apparent to see when the old fluid has been replaced with the new fluid, as the color changes from blue to gold or vice versa.

Note: The photos and instructions shown bellow are for early 986 but all of the water-cooled Porsches are very similar in this regard.

        The Brake Fluid Reservoir is 
        located in the front trunk, on 
        the driver’s side.  Locate it 
        and see what color brake fluid 
        is in there now. If this procedure 
        has never been done before, 
        most likely gold color fluid will 
        be present as that is the OEM.


You can lift the four wheels off the ground and remove them (my preference) or you can remove them one at a time (more time consuming).

Start with the furthest wheel from the reservoir first and then work towards the closest.  the recommended sequence is: 1.- Right rear, 2.- Left Rear, 3- Right Front, 4.- Left Front and 5.- Clutch Master Cylinder (for manual transmission cars).  The procedure is the same for each wheel.

• Choose the Brake Fluid 
  to use and empty a newly 
  opened can into Power Bleeder.

• I like to place the Power 
  Bleeder inside a bucket. 
  In case of any leaks or 
  spills, the bucket will 
  serve as a secondary 
  containment vessel, which
  can avoid possible damage
  to your car as Brake Fluid
  can strip paint.

• Pump up the pressure in the Power Bleeder to 20 lbs / sq.in.

  Starting with the right rear:
• Uncap both caliper nipples
• Connect a clear hose to the
  inside nipple and route the 
  other end to a clear plastic
  bottle for collection.
• Using the 11 mm wrench
  slowly turn the nipple (CCW)
• Observe the fluid coming out
• Once you notice the change
  in color, close nipple by
  turning clockwise.  This does
  not have to be too tight.
• Move the tube to the outer 
  nipple and repeat the procedure.  Note that the time for new fluid to flow 
  is greatly reduced, as it only has to flow from the inner part of the caliper
  to the outer part.

• Now you can repeat the same procedure on the other three calipers.
  Periodically, check the Power Bleeder’s pressure and pump back to 20 lb
  when necessary.

• Before you start bleeding the clutch, you 
  need to completely depress the clutch pedal, 
  to open the master cylinder.  
  The pedal needs to be depressed for the entire 
  clutch bleeding operation.
  Either have an assistant depress the pedal, or 
  cut a piece of two-by-four (2” x 4”) lumber so 
  that it can be wedged between the depressed 
  clutch pedal and the seat rail, as shown.

  When finished bleeding the clutch you will need
  to manually pull back the clutch pedal, as it will
  not initially return on its own, when you remove
  the lumber or the assistant’s foot.

• Bleeding the Clutch is the 
  toughest part of the procedure
  because the bleed nipple is 
  difficult to get to comfortably.
  It is located on top of the 
  transmission, on the driver’s
  side and and has a black 
  plastic cap to protect the
  nipple from dirt.

• Once you locate it, you’ll
  have to place the 11 mm
  wrench on the nipple (here
  the closed end works better)
  then insert one end of a 
  (longer) clear drain hose onto
  the nipple and the other end
  into a collection bottle.

• Slowly open (CCW) the nipple
  and let the system flush until
  you see new fluid.

• Tighten the nipple, remove the
  drain hose and recap.

• Slowly let off the pressure on the Power Bleeder by unscrewing the
  pump.

• Check to make sure that 
  the Brake Fluid level in 
  the reservoir is at the
  MAX indicator, with the
  car level.

• Make sure you clean up any
  Brake Fluid spills because
  it can strip paint from painted
  surfaces and is corrosive.
  Brake Fluid will wash off with
  water from hands, tools or clothes.

• Don’t forget to do this every two (2)
  years of before every DE or track
  day.



Happy Boxstering,
Pedro
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