In a message dated 11/5/99 11:21:52 PM Pacific Standard Time, skye@ffwd.com
writes:
> > > James, I am not recommending, nor did I ever recommend, re-using brake
> > > fluid. I am referring to the only sure method of achieving a hard
pedal
> > > on an LBC. If you use the pump-up, loosen bleeder, "squirt," tighten
> > > bleeder, do it again, method, you will never get a truly hard pedal
> snip
> > ..factory shop manual I have ever seen in my 30+ years of working on
cars
> > professionally warn never to reuse fluid (this is the guy who designed
the
>
> > system). The company that I work for now (Volvo) even says not to reuse
> > freshly bled fluid. Fluid makers also make the same warnings.
>
> You missed Rocky's point. You're not re-using freshly BLED fluid -
> you're re-using FRESH FLUID. It's not brake fluid that has been sitting
> in the car for x months, you just put it in (after a drain & flush).
>
> I am going to try Rocky's method the next time I bleed. It seems like
> a really good idea IMO.
>
Skye,
You missed my point. Think for just a second. If the fluid goes in the
master and comes out a bleed screw then it is freshly bled fluid. It is no
longer new. This is what Volvo warns about in their shop manuals. New (in
my mind at least) denotes out of a fresh can. Once it is in the car it
becomes used. And once you remove it from the system it is bled fluid. The
problem as I have said before is the water that will be present in the
remaining old fluid. As the new fluid flows through the system on its way
out it will mix with the old fluid and the water will then be present in the
system. Now if you bleed the system like you are supposed to (not reusing
fluid) the water gets diluted down to a point where it is no longer a factor
and there is only fresh fluid in the system. If you recycle the "new" (not
really though) fluid the water gets put right back into the system. Maybe
I'm just a little anal about this subject as I have experienced boiling brake
fluid in both brakes and clutches. I don't even save a partial bottle of
brake fluid. I open a new one each time I go to use any and throw any
remainder away.
Now let's discuss just what is so magical about Rocky's method and why.
Does this reusing method work because air won't go out of the system until
the fluid has gone though the master twice? How do it know? Does it work
because of some hyper dimensional shift? I don't think so. The answer as
best as I can understand is that having the bleed screw open and a column of
fluid above it allows for bubbles to work their way out without any hassle.
If you use the bottle and hose method that I suggested a couple of posts back
you will have the column of fluid above the bleed screw and you will not risk
any water remaining in the system.
Here is what I wrote the other day.
<Snip>
Now if you believe that this is the only way to a high hard pedal there is a
safe, no argument way to do this. Instead of running the tube back to the
master try this. Get a soda bottle (clear) find a piece of tubing that just
fits over the bleed screw. Cut a piece of this tubing about 12-18 inches
long. Using mechanics wire or safety wire secure the hose to the neck of the
bottle (make sure that the hose is not squished by the wire and air/fluid can
pass) Oh yeah I almost forgot, have the end of the hose about 1/8 inch off
the bottom of the bottle. If you want to get fancy, make a hook with the
wire, so that you can hang the bottle off part of the car. Place a small
amount of fluid in the bottom of the bottle to cover the end of the hose.
How to use: Place hose on bleed screw. Route the hose so that it goes up
and then down into the bottle. In other words at least part of the hose needs
to be above the bleed screw. Open the bleed screw and pump the pedal slowly,
don't let the master go dry. When you are happy with the amount of fluid
that you have pumped through the system close the bleed screw and disconnect
the hose. Dispose of the fluid correctly (do not pour into drain oil, the
chlorine in the brake fluid turns recyclable oil into hazdours waste.)
There everybody is happy NO reuse of fluid and the hard pedal that Rock
wants.
Can we move on to another cat thread now?
I swear this is the last I'm going to write on this subject.
BTW I had a small kitten treed on the roof of my garage last night. I wanted
to keep him for some LBC use but the family made me find him a good home.
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