Tony :
While I can't match Mr. Wall's qualifications, I feel some of his 'facts'
are distorted.
If you dump a "big globule" of water into any brake system, you're in
trouble regardless of fluif. Beyond 3% water content, the boiling point of
glycol also goes to 212F. Since glycol goes to 3% water content all on it's
own, any water added after that will cause the exact same situation as
adding water to silicone.
Also, the saturation level of water in glycol is temperature dependant. If
your master cylinder is open to the air (as most LBCs are), then the glycol
will absorb water in warm weather (or any time the air under the hood is
warm), and then let it separate inside the lines/cylinders in cold weather.
The cycle repeats every year, continually sucking more water into the
system.
I have been using silicone for many years, and I have yet to see the
"gelatin like goop" that Mr. Wall describes, let alone have it "plug up
metering orifices or cause pistons to stick". The parts I've disassembled
have always been clean (well, except the clutch slave that got drug through
the dirt <g>).
Last, while I'll agree that DOT 5 is not the best choice for racing (racing
fluif changed every few races is better), I doubt seriously that you can
flush any reasonable amount of water out of a caliper by "cracking the bleed
screw". After all, the bleed screws are at the top, and as Mr. Wall just
finished telling us, water sinks to the bottom.
Frankly, this letter has been passed around, and copied so much that I feel
it has achieved the status of urban legend, right along with the guy shot in
the leg after using a 22 cartridge for a fuse in his pickup truck. It's
also internally inconsistent, just like the one purporting to be from
Lockheed/Girling.
Randall
Tony Gordon wrote :
>
> It must be spring; we're debating brake fluifs once more:
> the following
> clip came from Dick Taylor (a very on-the-ball 6pack list
> subscriber) and
> it stopped the debate dead ... (not that I wish it to end, mind you,
> there's still too much salt on the roads in mid-MI ....), but
> it is unusual
> to find an answer so compelling.
>
> Tony Gordon
> Midland, MI
>
>
> >Date: 15-Feb-2000 23:18:23
> >Subject: Tech Tip: Brake fluid debate
> >
> >..And the great debate goes on. The article attached may shed some
> >light on why some owners who have changed to the silicone
> fluid report
> >some "sponge" in their pedal...Dick Taylor
> >
> > http://www.xs11.com/tips/maintenance/maint1.htm
>
>
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