I wanted to thank Rocky for his suggestion. One of my projects for the
weekend was a long-deferred brake bleeding session. Since replacing the rear
cylinders over a year ago, two attempts at bleeding had still left some air
in the lines, resulting in noticeable pedal "pump up". I checked my mail on
Sunday morning, saw his post, and said "eureka!"
I went to NAPA and picked up 8 feet (wild-ass guess as to length) of clear
hose. It worked fabulously -- you could see any air bubbles travel all the
way to the master cylinder, there to dissipate harmlessly. The only hitch
was that the hose was a tad short for the offside rear brake -- if you try
this I recommend 9-1/2 feet as the proper measure for a B. Fortunately I had
another 2' piece of hose which formed a tight slip fit over the other. The
hose I bought was a perfect fit for the front brake bleed nipple -- for the
rear I used the elbow fitting from an Ezibleed kit. (side rant: radically
different sized nipples front and rear -- what's with that? I guess it would
be have been too easy to have used the same wrench and hose all around...).
It occurs to me that this technique is essentially the same as "bench
bleeding", which is often recommended when installing a new master cylinder
-- it just includes the entire brake line in the loop.
One other comment: this technique requires some care if you use DOT 3 or 4
fluid, and happen to have good paint on your MG (not an issue in my case),
since you wind up draping the hose all over the place, and it is well known
that once you get any brake fluid on an object, it pretty much becomes
saturated.
on 4/22/02 6:17 AM, Bob Howard at mgbob@juno.com wrote:
> Rock,
> One of the guys in our club recirculates the fluid as you suggested,
> with the variation that he hooks the long tube to an inline fuel filter
> before letting the fluid back into the MC.
> Bob
>
>
>>
>> 5. Assuming that by this time there is nothing in the system but
>> new, clean fluid (don't do this next step unless the fluid is
>> clean), I then run a looooong piece of the tubing from each bleed
>> nipple in turn into the master cylinder reservoir and then
>> continually pump the brake pedal and watch the plastic tubing for
>> particulate contaminants (if they appear, I take the end of the tube
>> out of the reservoir and direct the contaminant into a waste fluid
>> bottle; same thing for any discoloration. Since there is no
>> necessity to keep the MC reservoir full, you can really circulate
>> the fluid; the bubbles will float to the top of the reservoir and
>> therefore be removed from the circuit. Once there are no more tiny
>> bubbles in the line (wow, sounds like a song title there), close off
>> the bleeder screw.
>> -Rock http://www.rocky-frisco.com
>
--
Max Heim
'66 MGB GHN3L76149
If you're near Mountain View, CA,
it's the primer red one with chrome wires
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