When I got my 4A the clutch slave was shot and so I had to rebuild it and the
masters before I could drive the car. I had decided to switch to DOT 5, which I
did for the brakes as well, just bleeding, bleeding, bleeding until I got most
of a quart through. Of course, since I did both ends of the clutch system,
everything was clear, I had blown out the clutch line with air. I was anxious
to drive the car, which we did, almost 5000 mi the first season.
The next winter I replaced all the brake hoses and rebuilt the 4 corners.
Inside the front calipers was what looked like salad dressing from the purple
lagoon, an emulsion of little gold speckles in the purple fluif, looked like
less than a quarter of the DOT4 remained . I don't remember the rears having
any DOT4 left in them.
The bleeders are meant to get air bubbles out, not as a path to flush, so I'm
not convinced you can get anything completely out by bleeding. Anyway it drove
fine, the brakes were always solid and straight. And after a total "renew" no
more golden DOT4. Some of you physical chemists may conjecture about the
compressibility / boil point of the emulsion and whether it poses a safety
threat. I can't speak to that, but it clearly worked for me. I'd say, go ahead,
switch by a good bleed down, but do the calipers soon as you can.
January
66 TR4A CTC74217LO
Date: Fri, 9 Apr 2004 15:26:37 -0700
From: "Randall Young" <ryoung@navcomtech.com>
Subject: RE: Clutch Fluid (DOT 5)
> "flush the lines out with methanol"
> IMO this might introduce a problem, so that the risk is greater than any
> benefit. Methanol has a fairly low boiling point [148 deg F] and might
> degrade the seals.
I agree, the methanol has to be completely removed. But it is compatible
with the seals, which is why methanol is specified, not isopropanol or
ethanol.
> Why not just flush with brake fluid?
Kinda silly trying to flush out DOT 4 with DOT 4 ... and DOT 5 will not
dissolve DOT 4 so it won't work either.
I lean away from the use of methanol myself ... just trying to answer your
questions.
Randall
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