Dangerous move to not use a pressure bleeder. The internal seals will be wiping over an  unused and probably rusty/gunged area when you depress the pedal fully to the floor, you may end up replacing the master cylinder as a result. I am speaking from experience!!
The idea not to let the level drop to low is to avoid air getting into the system, I would not let it drop below the clutch outlet port on the reservoir for obvious reasons.
100cm3 is 100 milli-litres. I do not know what it is in that other archaic means of measurement!
John.

  ----- Original Message ----- 
  From: Brian Kelly 
  To: vanagon@GERRY.VANAGON.COM 
  Sent: Tuesday, August 28, 2001 19:27
  Subject: Brake Fluid Change

  Hi, 

  I'm about to replace the brake fluid in my 86. 
  I'm confused by reading Bentley. From what I gather, it says never to reduce 
  the fluid level below the minimum mark. To follow the refill chart for each 
  brake cylinder when bleeding the system. 
  As a matter of interest what problem do you encounter draining the whole 
  system? 
  This would be the case if you were changing to silicon fluid. 

  What is the equivalent measurement of 100 cm3. as is mentioned in the Bentley 
  directions. 47.8A. I intend doing the procedure without the use of a pressure 
  bleeder. 

  Any tips gratefully accepted. 

  Brian Kelly 
  86 GL Westfalia. 

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