Bleeding dual cct brakes

["Graham Hilder" <graham.hilder@domain.elided>]

Greetings Alfisti,

In Digest 914 Scott described a method of bleeding or fluid changing for =
dual cct systems, which involved doing the front and rear calipers on one =
side of the car simultaneously, and using the pushl/open/close/release =
cycle of manipulating brake pedal and bleed valves. On this topic, I have =
found it's much quicker and easier to do every bleed point on the car at =
once, and furthermore, not to worry about the repetitive open-close =
business. I just connect my tubes and jars to every bleed screw, open the =
whole lot, and pump away until all tubes flow clean and bubble-free. Then =
close the lot. Scott mentioned a somewhat similar method but had reservatio=
ns about it, but I've found it works really well, assuming you have =
snugly-fitting tubes which can't slip off while you're not looking. =
Longest part of the job is setting up all the simultaneous tubes and =
jars...... 3 for an Alfasud, 6 for an Alfetta. But once ready, the actual =
fluid job itself is done in a jiffy.  And single handedly. And no =
contortions getting up and down on your knees to open and close front & =
rear bleed screws untold times  (or if it's an Alfetta, no repeated =
crawling in and out under the car to open and close those pesky inboard =
rear bleeders).

In Digest 916, Jack described an even easier method, which I believe in =
books is known as the gravity bleed...... i.e. just open the bleed screws =
and let the fluid run out of its own accord until clean. I have tried this =
method but have found the fluid seems to flow so slowly that I get tired =
of waiting for it to run clear and usually give up and go and get my =
simultaneous tubes and jars as above. I must try it again some time =
though.=20

I would heartily agree with Jack's recommendation of substantiallly =
emptying the old fluid from the reservoir before adding your new fluid. If =
not, your clean new fluid immediately becomes discoloured by the large =
amount of old stuff in the reservoir, and you may have to pump an awful =
lot of new fluid through the system before you have a definite and =
complete and unadulterated colour change. The emptier the reservoir to =
begin with, the sooner you'lll see for sure that the emerging fluid is all =
new. Jack suggested taking a turkey baster and sucking out the old fluid. =
But even simpler (and with no risk of nasty fluid spillage if you should =
fumble!), I just open the bleed screws and pedal-pump out the old fluid =
via the brake system itself, into the tubes & jars.  Just watch that =
reservoir level like a hawk while you're doing this though....!!!!!=20

The same ideas as above go equally well for clutches too.  (And it's =
bloody handy on an Alfetta with that pesky under-car clutch slave).=20
Graham Hilder,
N.Z.
(Alfasud, GTV, Alfetta GT)

P.S.   All the above I've done heaps of times on the Alfetta and lots of =
Alfasuds. I can't say if it'd work for 105 Alfa brakes though, as I've =
never had any luck bleeding my GTV brakes any which-way I've tried. Mind =
you I don't really know what state the master cyl, boosters and other =
components are in...... the GTV brakes need a good going over so I can =
start from a clean slate.
GH

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End of alfa-digest V7 #925
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