Brake lines (the pipes) are completely attached to the body/frame of the car
so there is no significant relative motion between one part of the line and
another. Any part of the line that is subject to flexing has a rubber hose
(front wheels, rear axle). That avoids the problem of fatigue cracking.
The clutch slave cylinder is attached to the engine/gearbox but the rest of
the line is attached to the body/frame so there is constant relative motion
as the engine moves on its mounts. That's why the clutch line has a hose
from the slave to the body of the car. If my copper pipe clutch bleeder
could be completely attached to the engine, like Doug's design, that would
be better.
Some alloys are more susceptible to work hardening and cracking than others.
I don't know the composition of the copper pipe I used. I'm going to leave
the pipe in place and monitor it to see how long it might take for problems
to develop.
It's sort of amazing that it took so long for someone to come up with a way
to put the bleeder in a way-better location. During our return from
Conclave in San Diego in 2008, my traveling companion complained that his
clutch wasn't working so well in the high altitudes of Colorado. We
suspected air in the line. Fortunately, he had Doug's extension installed.
We stopped at a NAPA store for some clear tubing and silicone fluid. The
bleeder made it a 5 minute job to bleed the clutch back to normal without
having to screw around under the car. That experience convinced me, and
when I got home I ordered the extension from Doug. I agree, it was well
worth the money.
Steve Byers
HBJ8L/36666
BJ8 Registry
AHCA Delegate at Large
Havelock, NC?
-----Original Message-----
From: Healeys [mailto:healeys-bounces at autox.team.net] On Behalf Of Bob
Spidell
Sent: Friday, May 12, 2017 10:35 AM
To: healeys at autox.team.net
Subject: Re: [Healeys] Clutch bleeder?
"... copper alloy, which is susceptible to work hardening and fatigue
cracking from vibrations from the engine"
I sure hope not, as I'm using 'cupranickel' copper alloy lines in part of my
brake system. According to the company I bought them from--yeah, I
know--the alloy is not susceptible to work hardening. Supposedly, these
lines are used by Aston Martin, I think Volvo and some others.
I'm guilty of buying a lot of tricky things--tools, especially--that look
like great ideas, but often end up on the shelf, never used. But, Doug's
bleeder extension was about the best $30 I ever spent.
Bob
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