That's true Fred. But I figure air enters the minute you open any joint
in the system anyway. My thinking was more to be sure all the alcohol is
out before sealing the system back up and refilling/flushing with brake
fluid. But Joe Curry makes a good point about the compressed air
introducing moisture or something even worse back into the system, so a
"drip dry" and patience (yeah, right) might be in order.
Actually, on my car I am simply replacing all the pipes & fittings, all
rubber hoses with flex stainless steel, rebuilding M/C, wheel cylinders,
calipers (replacing stock pistons w/stainless steel). I'll be using DOT4
or DOT5.1 fluid (aka - paint remover), not silicone based. I will not
need to use the denatured alcohol to flush the system, but have used
plenty cleaning up & reconditioning the various cylinders. Every manual
(TR & other) I've seen says you should only use denatured alcohol or the
compatible brake fluid in the system, nothing else. The brake system is
about the most critical on the car & worth doing right.
BTW, you may already know this but it bears repreating... never fully
disassemble a Girling caliper (beyond removing pistons, bleeder valve).
There are handy bolts there keeping the split assembly together. Leave
em alone. I understand reassembly requires special torquing procedures.
Also keep strong cleaning fluids away from the joint, as there is a
rubber O-ring in there, which if damaged, would ruin the caliper
entirely. If the caliper is leaking from the center seam, it's time to
get a whole new unit.
Lastly, does anyone out there have a caliper piston dust (outer) seal? I
have one torn (don't be to heavy handed putting those pistons back in!)
and hate to buy a full rebuild kit (from Moss or B.V.) to get just one
seal. Alternatively, know anyone who sells the pieces, not only the full
kit?
Alan Myers
San Jose, Calif.
'62 TR4 #CT17602
fred thomas wrote:
> Joe Curry wrote:
> >
> > Alan,
> > One problem with using compressed air to blow out brake lines is
> that
> > unless there is an adequate desiccator in-line, compressed air
> typically
> > carries a great deal of moisture. Because silicon based brake fluid
>
> > does not absorb moisture the way other types do, you could be
> > introducing a different type of contaminant into the system.
> >
> > Just a thought!
> >
> > Joe Curry
> >
> > Alan Myers wrote:
> > >
> > > How about a turkey baster? Might need a rubber hose on the end to
> bring
> > > it down small enough for the brake pipes. I agree you should keep
> the
> > > alcohol away from the rubber parts. Does your car have the
> restrictor
> > > inline to the rear brakes? Might want to remove it before
> flushing. The
> > > manual I have says to use "methylated spirits" which I looked up
> in my
> > > British to American translation dictionary and found was plain old
>
> > > denatured alcohol solvent (get it at a hardware or paint store).
> Might
> > > want to blow a little compressed air to push out as much alcohol
> as
> > > possible before reassembling. Then be sure to "waste" plenty of
> the
> > > fresh, clean brake fluid as a final flush.
> > >
> > > Alan Myers
> > > San Jose, Calif.
> > > '62 TR4 #CT17602
> > >
> > > Philip E. Barnes wrote:
> > >
> > > > At 11:06 AM -0700 8/13/98, John Cowan wrote:
> > > > > I plan to flush the brake lines on my TR-4A with alcohol
> before
> > > > >reinstalling the Master Cylinder. The best approach would seem
> to be
> > > >
> > > > >disconnecting one line from its slave cylinder, starting from
> the
> > > > farthest
> > > > >most, flushing out the open line, reconnecting it and then
> moving on
> > > > to the
> > > > >next. Then, when all four have been done and reconnected,
> opening up
> > > > the
> > > > >bleed valves one at a time on the slave cylinders to flush them
> out,
> > > > too.
> > > > >Then, repeating the whole process with fresh brake fluid, using
> the
> > > > >reinstalled MC.
> > > > > The question is, what can I use initially to pump the
> alcohol
> > > > through
> > > > >the system? I don't want to use the MC, since I only want to
> put
> > > > brake
> > > > >fluid into it. Any suggestions would be appreciated.
> > > >
> > > > I'd be very reluctant to run alcohol through anything other than
> the
> > > > brake
> > > > pipes themselves. (Perhaps I misunderstand you.) Using a large
> syringe
> > > > to
> > > > force the alcohol through the pipes ought to work. I'd try to
> get a
> > > > good
> > > > lab-grade isopropyl or methyl-alcohol; they are very dry. Blow
> them
> > > > out
> > > > with compressed air when you're done.
> > > >
> > > > Phil Barnes (peb3@cornell.edu)
> > > > Cortland, NY (nowhere near New York City)
> > > > '71 TR6 CC61193L (21 year owner)
> > >
> > > --
> > > MZ
> >
> > --
> > "If you can't excel with talent, triumph with effort."
> >
> > -- Dave Weinbaum in National Enquirer
>
> If I may add = why do we bleed brakes = to remove air, and trying to
> blow
> the system out will certainly leave air. (also moisture)
--
MZ
|