How to.... Change the brake fluid--NA (MK1) NB (MK2)

Technical Area How To Guides
2

It’s easier to remove the road wheels to carry out this task so you’ll need to ensure the car is safely supported.

1. Remove the top of the master cylinder reservoir.
2. Using a turkey baster, suck out as much of the old dark inky fluid as you can.

3. Clean any sediment out of the reservoir with a clean, lint-free rag. (Do not spill any brake fluid on any painted surfaces, it will strip the paint. In case of spilage nutralise brake fluid with lots of water.)

4.  Fill the master cylinder with clean brake fluid that is the correct specification for your car (normally DOT 3, DOT 4 or DOT 5.1) 

5. Using a piece of clear plastic tubing (aquarium tubing works fine), push one end of the tube over the brake nipple.

6. Put the other end of the tube into a clear bottle (approx 500ml capacity is sufficient) with an inch or two of clean brake fluid in it. (This will keep air from being sucked back into the brake cylinder.)

7. Start at any corner and open the bleed nipple about 1/4 of a turn. Most people prefer to start at the wheel furthest from the master cylinder.

8.  Ask an assistant to sit in the driver’s seat and slowly depresses and release the brake pedal about 12 times with an even force and hold it down after the 12 stroke. Watch the bleed pipe and check the air is not drawn back up it into the caliper. The helper should shout “down” when the pedal is down as far as it will go. With the pedal held down close the bleed nipple.

9. Now top up the master cylinder reservior before moving on to the next brake. Never let the reservoir get too low, or air will be sucked into the master cylinder.

10. Repeat steps 5 to 9 on the remaining brakes.

1 Like