Date: Wed, 13 Jan 2016 20:20:19 -0500
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: More leaks
In-Reply-To: <02eb01d14e32$e92a2640$bb7e72c0$@gmail.com>
Content-Type: text/plain; charset="us-ascii"
Clamped hose connections need more than friction to hold the hoses in place.
The barb provides a stop and an additional sealing surface as the hose gets
pushed off, the reduced hose diameter ahead of the clamp becomes like a
compression seal which increases with pressure. When a customer tells me
they can't afford this repair I suggest they make sure their tow plan will
get them home and maybe they should even save for an engine.
So far every VW engine I have had to replace has had a cooling system
failure in its past. Maybe not immediately but sometime there was a failure.
I have seen these hoses separate a number of times and if they do go at
highway speeds some engine damage is going to happen. Loose that coolant
with some red hot parts inside and just think of letting a pot (especially
aluminum) boil dry on a stove?
Do some type of fix with epoxy or something to get a hose stop back in
place.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Stuart MacMillan
Sent: Wednesday, January 13, 2016 1:48 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: More leaks
There are lots of ways to fix this, but I was thinking about why it happens.
It's the corrosion of the sleeve. Corroded metal expands at the surface and
allows coolant to get in between the wall and tube, which is a lubricant.
The clamp on the hose is not strong enough to keep the hose from working off
as the sleeve moves out.
The real fix would be a new stainless steel sleeve, but it's taken 28 years
for this one to fail, and the rough corroded surface should actually grip
the plastic better when it's tapped back in and clamped.
Stuart
-----Original Message-----
From: vw_van_fan_Mark [mailto:madvws@cox.net]
Sent: Tuesday, January 12, 2016 6:53 PM
To: Stuart MacMillan; vanagon@GERRY.VANAGON.COM
Subject: Re: More leaks
I just use a propane torch on low to gradually heat the metal insert and
then I tap it back into the plastic pipe. If the barb end of the plastic is
gone, I don't worry about it.
The plastic pipe end was not molded around the metal insert sleeve. The pipe
was machined inside and then the insert was inserted.
Mark
Stuart MacMillan wrote:
> Yep, the plastic barb end was in the hose and is now removed.
> Apparently a previous attempt at repairing the leak used two hose
> clamps, one was only on the extended steel flange, and the other was
> on the very end of the hose about 1/4" over the tube, and at some
> point slipped off. Now I know why is was just hanging there on the
plastic tube.
>
> I'm reluctant to drill into the tube since that creates stresses that
> can lead to splitting "down the road". It looks to me that clamping a
> backstop for the steel flange into the hose (the GW brass insert) will
> adequately hold the flange in the tube. But if it works itself out
> again
it would now
> pull the hose off the tube. . . . Maybe I should use a screw down clamp
on
> the tube rather than the spring clamp?
>
> Stuart
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On
> Behalf Of Dennis Haynes
> Sent: Tuesday, January 12, 2016 5:48 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: More leaks
>
> The plastic end was molded around that metal tube and the molded part
> included the barb to hold the clamped hose. For the tube to slide out
> part of the pipe is missing and maybe still inside the hose, usually
> stuck at the next bend. The GW kit is not a fix unless you rivet that
> inner sleeve in place and then deal with the hose being deformed on
> the inside. The fix is one of the replacement pipe kits. As for
> discoloration originally those pipes were bright white, not yellowish
> brown. With care the pipes can be replaced without dropping the tank.
>
> Dennis
>
>
