Topica Loopframe_Guzzi Archive


Subject: RE: phosphoric acid

Author: murp-@aol.com

Date: May 9, 2001, 10:57 PM

Post ID: 1706660080


Mike,
I used phosphoric acid on my tank when I used the brand name product
'Creme' to coat my tank, but had some problems. The supplied phosphoric
acid is diluted to produce about 2.5 gallons, which is used to get rid
of the rust in the tank. The instructions said that if this amount did
not fill the tank, then the tank should be rotated every once in a while
to get the whole tank. I did this for hours, but still had rust in the
tank. I phoned the manufacturer, who told me that when the phosphoric
acid is used, rust forms immediately after the acid leaves the surface,
so the turning method for full coverage does not work. He said that the
whole tank must be filled with the proper concentration of acid for all
the rust to be removed.
The above does not address your question, but I thought you could
benefit from my experience. I ended up buying another whole kit (for
$26) just to get the required amount of phosphoric acid. Later, when it
was too late, I found phosphoric acid of the right concentration in the
'tile and floor' section of Home Depot.
The "Creme" kit uses Methyl Ethyl Ketone (M.E.K.) immediately
following the phosphoric acid. It is used to absorb water in the tank
prior to coating with the "Creme" coating, which is some kind of
polymer. I was told that it was important to rinse out the tank with the
M.E.K. quickly, and to coat it with the "Creme" without letting the tank
sit for more than a few minutes.
So, I think it would probably not be wise to remove the rust with
phosphoric acid unless you are going to coat the tank afterwards.
There are some other products (one of which is Rustol made by Sudco)
which will remove rust without requiring an additional coating, however
this is quite expensive ($49 for enough to do a tank).
If I had to do it over, I would buy one "Creme" kit for $26, and
then get the additional required phosphoric acid from Home Depot. The
whole thing will cost about $30.
Brian
'74 Eldo
'78 T3



mike skaggs wrote:
 I understand this is the stuff to use when cleaning out a tank....does
it
have to be neutralized...?

Mike
www.classicguzzi.com

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