Re: Changing the brake fluid on my '90 100

[steveb@newkla.kla.com (Steven Buchholz)]

Brooks wrote:
> >   I was reading somewhere that brake fluid should be clear. Mine is as 
> >brown as motor oil. It hasn't been changed since I got it ~1-1.5 years 
> >ago, and it doesn't look like it was changed anytime recently before 
> >then. I was going to change my brake fluid, but then I realized, I had no 
> >idea on how to do it! 
> >   Do people on this list commonly do such a change? Would someone be 
> >gracious enough to give me some 'idiots guide to brake fluid changing' 
> >text? 
> >
> >Thanks in advance...
> >
> >Brooks
> >
> 
... to which Nick responded:
> Change it, soon, before the water it has absorbed rots away your entire
> braking system from the master cylinder to the calipers!
> 
> Now that I've scared you...the good news is it's dead easy. Simplest way
> is to take the wheels off one at a time, connect clear tubing from bleed
> nipple on caliper to a big glass jar, with the end of the tube submerged
> in some fresh brake fluid. Loosen bleed nipple, using preferably a box-end
> wrench, because rounding off the flats on the nipple will make you sad.
> Slowly press the brake pedal to the floor repeatedly, until new, clear fluid
> starts coming through the tube with no air bubbles. Keep the reservoir topped 
> up with new fluid as you work to stop air getting in.
> 
> Repeat for all 4 wheels, working from the furthest away from the master cylinder
> to the nearest.
> 
> Some people like to use a friend to pump the brake pedal, while they open
> and close the bleed nipple on each stroke. I find this unneccessary if you
> keep the tube submerged in the jar.
> 

... then Steve puts in his two cents ...
If you don't have someone helping by pressing the brake pedal you're gonna
need a long hose to be able to see when the fluid gets clear ;) (sorry, 
couldn't resist)

One additional tip ... I recommend that you get as much of the old fluid
out of the reservoir before starting the process.  It is usually fairly 
easy to get the fluid out of the rear reservoir, but the front is a lot 
tougher.  Once this is done top the reservoir up all the way with clean 
fluid, then start the procedure as Nick described.

It is also recommended that you remember to bleed the clutch at the same 
time.  It amazes me that I have to specifically ask the dealer to do this
when I go in for a brake fluid replacement ... guess it must really be
*clutch* fluid.  

I bought one of those MityVac (sp?) thingies to try to make it possible to
do a 1-person job, but was frustrated by air leaking past the threads on 
the bleed nipple.  I just saw a post the other day on another list that
recommended using Teflon tape on the threads to solve the problem.

Steve Buchholz
s_buchho@kla.com