Carol:
Pete Chadwell here... veteran of many, many rebuilds in this area. Here's
my procedure for bleeding the clutch. Make sure that all connections are
tight, obviously, then get a helper to pump the pedal. Put the hose and
wrench onto the bleed screw and after filling the reservoir, have your
helper pump the pedal SLOWLY three times. On the third stroke they should
hold the pedal down and at that point you crack open the bleed screw and
hold it open for just a second or two. Then close it and signal your
helper to release the pedal. You'll have to repeat this several times
before you see fluid coming out of the hose. Remember to keep the
reservoir full. (refill every three cycles or so) Continue the pumping
cycles until you no longer get air bubbles coming out of the bleed screw.
This entire process should not take longer than, say, fifteen minutes at
the worst.
You can also, as an extra measure, actually SIPHON the fluid through the
circuit using gravity. Since the master cylinder is much higher than the
slave, the fluid wants to flow to the slave anyway. Once you have fluid
throughout the system, you can actually just open the screw with the pedal
released and let the fluid flow through the system. It will carry any air
out with it, and actually does a better job of evacuating air because you
don't get any cavitation, which can result from fluid surging rapidly
through openings and around corners, introducing air into the system.
Remember to keep the reservoir full!
Incidentally, the "gravity" method of bleeding is explained further in
Carroll Smith's book "Prepare To Win," in a treatise written by Mac Tilton
on the subject of bleeding brake systems. Obviously, it is most critical
to get ALL the air out of a BRAKE system in particular, and ESPECIALLY in a
racing car that goes 180 mph!
Have fun!
Pete Chadwell
1973 TR6 CF10732
You wrote:
>Re-build clutch master and slave this weekend, lubed with clean fluid
>and re-installed the pistons. Then reconnected parts to Sybill.
>Foolishly attempted bleeding of system *before* building up pressure in
>system to ensure bleeding would work (too much beer night before!).
>
>After pumping the clutch pedal 300+ times, (with bleed screw closed),
>I'm wondering: 1) How long should it take to build up the pressure in
>the system when it was completely dry ? 2) Do I need to *manually* start
>the slave cylinder piston to begin a vacuum process that will draw the
>fluid from the master ?
>
>Thanks (yet again!) in advance --
>
>Carol Zingone
>74 TR6 -- Sybill
>
>
>BTW: Sybill sounded a bit ragged when I turned her over, oil pressure
>however, went right up to 75 which was a nice sight ! :-)
>Discovered a lower carb leak, pretty steady from the front carb, so a
>carb rebuild may be in the near future, not a nice sight :-(
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