Last night I finally changed the brake fluid in my '88 Westy, which I
haven't done in the 3 years since I've had it. With my Jetta, I've
been in the habit of changing it every 2-3 years, which has saved
me from replacing rear wheel cylinders which generally corroded
away in the old fluid.

I started with 4 small bottles of DOT 4 fluid (Castrol LMA and
Pennzoil), and used about 2/3 bottle on each of the rear brakes and
the clutch slave cylinder. I attached a few feet of clear tubing to the
bleeder, and inserted the end a 1 liter empty jug. Since the old fluid
was quite brown, it was easy to tell when the new clear fluid has
flushed through, at which point I closed the bleeder, then opened
slightly, bleed a bit more to clear any air, then closed. (Hint: spray
wd-40 or similar on bleeders before starting, and have a small pair
of vice grips, as bleeder screws are likely seized.)
After about 5-6 pumps of the clutch, it suddenly got *very* easy to
depress the pedal, which got me worried that I had blown the master
or slave seals :-(  I finished flushing the clutch and moved on the
fronts, which require only a small amount to flush out.

The left front brake bleeder cap was full of rust when I popped it off.
Hmmm. The bleeder was quite seized, and no fluid escaped when I
loosened, except some which seeped around the threads when it
was very loose. I pumped to see if it would force the rust out. No
luck. I inserted a small nail and worked it around, then tried again. A
large amount of rust chunks flushed though the hose, until it was
finally clear. I don't know if the rust has reached the caliper bores,
but I hope not. After seeing this and the colour of the fluid, it's no
wonder I had brake fade on long hills!

After finishing, I tested the clutch, and discovered it was fine, but
was suddenly much easier to depress. Possibly I saved myself from
buying a clutch cylinder as well...

I highly recommend this cheap and easy maintenance task to
prolong the life of your brake components and improve braking.

Shawn Wright, I.T. Manager
Shawnigan Lake School
swright@SLS.bc.ca
http://Zuiko.sls.bc.ca/swright
http://www.sls.bc.ca