Date: Thu, 29 Nov 2007 21:04:26 -0800
Reply-To: Scott Daniel - Shazam <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Shazam <scottdaniel@TURBOVANS.COM>
Subject: Re: ONE MAN only out of many
In-Reply-To: <ac1f198b0711291701y274cc7b3kbcdd2da6229e9807@mail.gmail.com>
Content-Type: text/plain; charset="iso-8859-1"
I'm glad you said that, two factors - you don't want to lubricate it - that
would make the hose slip off possibly, especially when hot.
And two - grease ( and oil ) eats rubber. Just notice what a nice oil leak
can do to a rubber engine mount over time. See my other two posts about
hi-tack ( only that one ) gasket sealer, and water soluble oil in the
coolant. Silicone sealant sounds all right. I don't think it would make
the hose stuck on there too badly for taking apart later.
Scott
www.turbovans.com
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Jim Akiba
Sent: Thursday, November 29, 2007 5:01 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: ONE MAN only out of many
On second thought, scrap the two clamps and the grease idea.. the
grease may weaken the hose and the first clamp will isolate all of the
stress on the hose to a single narrow cross section and make it fail
prematurely... better would be to coat the dry aluminum with a good
high-temp stable(perhaps brushable silicone/RTV coating) and then
install the hose over it. Just a couple more crumbs for the table...
Jim Akiba
On 11/29/07, Jim Akiba <jakiba@bostig.com> wrote:
> Whoops forgot to answer to the "how to stop it" part... it's tedious,
> but loosening your clamps and moving the hose, thus removing the
> "stagnant" coolant(losing some too) between the rubber/AL should
> help... also using heavy grease and two hose clamps (one further up,
> before adding coolant should theoretically help. The idea being DON'T
> have any water/coolant in between the rubber and the hose at all. Not
> sure it's worth it though... healthy coolant and timely changes and
> hose replacements always seem to work for me.
>
> Jim Akiba
>
>
>
> On 11/29/07, Jim Akiba <syncrolist@bostig.com> wrote:
> > To answer the most important question, it's likely the lack of
> > movement of the coolant in that area. Check out this abstract on an
> > sae tech paper titled "Investigation of Fluid Circulation Effect on
> > the Internal Corrosion Resistance of Automotive Heater Core".
> >
> > The Al-Si cladding they talk about on the cores would be roughly
> > equivalent to the common AL-Si alloys used in casting such parts as
> > water pump inlets etc, so I don't see any reasons the last
> > sentence(and more importantly its logical inverse) wouldn't also hold
> > true. If you are interested in the exact mechanism that causes this, I
> > can dig further.
> >
> > "An experimental test bench has been developed to study the effect of
> > flow on the corrosion behavior of the internal surface of heater core
> > tubes. The experimental device allows the electrochemical behavior of
> > the system to be investigated under different liquid compositions,
> > different temperatures (between 40 and 80°C) and different fluid
> > velocities (between 0.5 m/s and 1.5 m/s) at different test duration
> > (up to 100 h). The study is focused on the water side corrosion
> > resistance of brazed AA4343/AA3003*/AA4343 material, i.e., the
> > residual Al-Si cladding. The increase of the temperature has a
> > preponderant influence on the corrosion rate by comparison with the
> > variation of the fluid velocity. The increase of fluid velocity rather
> > limits the corrosion degradation."
> >
> > Jim Akiba
> >
> >
> >
> >
> > On 11/29/07, Zoltan Kuthy <zolo@foxinternet.net> wrote:
> > > Probably the most important question to answer is; what makes
corrosion between rubber and aluminum? The other is; how to avoid it?
> > > Although, I have put this question up more than once within a year,
nobody even attempted to try to answer it, but ONE.
> > > This list is fighting and dreading this symptom the most, yet there is
not enough knowledge to know how to stop it.
> > > Is there more than ONE out of the hundreds of members who knows, or at
least think he knows?
> > > Anyone?
> > > Zoltan
> > >
> >
>
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