[Spridgets] brake bleeding problems

[Bud Osbourne]

Marc,
Sometimes the calipers trap air and are a real bear to bleed out.  From
the sound of it, you are working by yourself on this.  Sometimes, it
helps to have 3 people: one to pump the brake pedal, one to operate the
bleeders, and one to keep the brake fluid reservoir filled.  By doing it
this way, the air has much less time to flow back to a "high point" in
the circuit, from which it can continue to frustrate your efforts to
expel it.
Bud Osbourne

-----Original Message-----
From: spridgets-bounces+abcoz=hky.com at autox.team.net
[mailto:spridgets-bounces+abcoz=hky.com at autox.team.net] On Behalf Of
Marc
Sent: Monday, July 30, 2007 2:05 PM
To: Spridgets
Subject: [Spridgets] brake bleeding problems

Ok, getting somewhat aggravated here, this shouldn't be so difficult...

73 midget, complete brake job, all three hoses, new wheel cylinders, 
rebuilt calipers, brand new lockheed master. Castrol  LMA fluid.

Using a long piece of tubing running from bleeder back to master, and 
starting from the longest run to the shortest, bled the system till no 
more air bubbles could be seen anywhere. Seemed good with a nice firm 
pedal. Car is still on stands, so cant drive it yet. Notice the front 
hubs seem locked, can't budge them by hand. Hmmm says I, let me crack 
the bleeders on the front and see what happens.

Cracked them just the slightest bit, and  the front hubs freed right up.

Once again brake pedal hits the floor with no resistance. Back to where 
I started -WTH?! 2 - 3 pumps builds up system pressure again, but it 
"just disappears" within moments, pedal will go to the floor. No fluid 
leaking, and had good fluid flow from each wheel (as determined by 
bleeding).

This isn't the first time I have done this job (albeit previously on 
MGB's). Never had any probs like this. What is going on here?

Have gone around multiple times tapping on lines & fittings to remove 
trapped air. Have bled using conventional method. Have bled by pump 
pedal several times to build pressure, then crack bleeder (closing it 
while pedal is held down of course).

Have checked the differential pressure warning switch - it is centered 
and working. No, I did not bench bleed the master as I had no fittings 
which would work with it.  My uneducated guess is that bleeding using 
the tubing as I did is pretty much like bench bleeding? We continued to 
circulate the fluid for a few minutes after the bubbles had disappeared 
thru the entire 12 - 14 feet of tubing... Could there be that much more 
air lurking in the system?

-- 

Marc

I'm taking the time for a number of things that weren't important
yesterday...