Date:         Sun, 8 Nov 2009 22:43:02 -0500
Reply-To:     David Beierl <dbeierl@ATTGLOBAL.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Beierl <dbeierl@ATTGLOBAL.NET>
Subject:      Re: You can blame Me - was: steel coolant pipes 82 diesel Westy
Comments: To: craig cowan <phishman068@GMAIL.COM>
In-Reply-To:  <d1ea9acf0911081801q525a725ct90a2b7e0fe1721d7@mail.gmail.co m>
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At 09:01 PM 11/8/2009, craig cowan wrote:
>The stainless steel "2 piece" pipes have a barb on each end where they
>couple that allows them to stay secure. It's a great theory that such
>substantial pressures exist in these pipes to blow off a hose clamped to a
>strait piece of pipe. I have however in the last 3 years of driving my bus,
>proven that this is not the case. When my steel pipes rusted out on my '85,

Hi Craig -- it's more subtle than that.  Hose clamp connections with
no mechanical retainer -- even double hose clamps -- are notorious
for *occasionally* getting milked off any pressurized line that
pressure/temperature cycles.  Vibration probably contributes.  It
doesn't take huge amounts of pressure.  It seems unreasonable since
you can't shift them by hand, but I've witnessed it myself on more
than one occasion.  That's why commercial connections invariably have
a retaining ring at the end of the pipe.  Believe that they wouldn't
put it there if it weren't necessary, as it's an extra manufacturing
step.  Like you I have flouted this and gotten away with it for long
periods, but that just makes me lucky, not a prophet. ;-)

Yrs,
d