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jt
July 14th 03, 02:37 AM
Got a pair of fuel-level senders and the cork floats have lost some of
whatever it was that was painted on them. These will be in tanks with
automotive gasoline. What should I use to seal them?

Larry Smith
July 14th 03, 02:46 AM
"jt" > wrote in message
...
> Got a pair of fuel-level senders and the cork floats have lost some of
> whatever it was that was painted on them. These will be in tanks with
> automotive gasoline. What should I use to seal them?
>
>

Somebody recommended Ambroid in a mailgroup recently. I can't attest to it
for myself, having long ago given up on cork and gone to a brass float.

Jerry
July 14th 03, 03:03 AM
Go to a local hobby store and get 'hot fuel proof clear dope"

Jerry in NC

"jt" > wrote in message
...
> Got a pair of fuel-level senders and the cork floats have lost some of
> whatever it was that was painted on them. These will be in tanks with
> automotive gasoline. What should I use to seal them?
>
>

Orval Fairbairn
July 14th 03, 03:38 AM
In article >,
"Jerry" > wrote:

> Go to a local hobby store and get 'hot fuel proof clear dope"
>
> Jerry in NC
>
> "jt" > wrote in message
> ...
> > Got a pair of fuel-level senders and the cork floats have lost some of
> > whatever it was that was painted on them. These will be in tanks with
> > automotive gasoline. What should I use to seal them?
> >
> >
>

I believe that the original treatment was shellac.

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Larry Smith
July 14th 03, 01:31 PM
Orval equivocated:

> I believe that the original treatment was shellac.
>
>

That was in them old glory days when gasoline did not contain volatile
additives.

Paul
July 14th 03, 03:49 PM
I've had good luck with polyester fiberglass resin. This is on floats used
with
a wire sticking up to see fuel level.
I have dipped them in resin and then shook off the excess. They don't
seem to float any lower and the resin resists auto fuel.

Cheers:

Paul
NC2273H


> Got a pair of fuel-level senders and the cork floats have lost some of
> whatever it was that was painted on them. These will be in tanks with
> automotive gasoline. What should I use to seal them?
>
>

Ed Sullivan
July 14th 03, 08:08 PM
Orval Fairbairn > wrote in message >...
> In article >,
> "Jerry" > wrote:
>
> > Go to a local hobby store and get 'hot fuel proof clear dope"
> >
> > Jerry in NC
> >
> > "jt" > wrote in message
> > ...
> > > Got a pair of fuel-level senders and the cork floats have lost some of
> > > whatever it was that was painted on them. These will be in tanks with
> > > automotive gasoline. What should I use to seal them?
> > >
> > >
> >
>
> I believe that the original treatment was shellac.

I don't know if there is enough alcohol in your auto gas, but alcohol
is a solvent for shellac.

Ed Sullivan

O-ring Seals
July 14th 03, 10:15 PM
On 14 Jul 2003 12:08:54 -0700, (Ed Sullivan) wrote:

>Orval Fairbairn > wrote in message >...
>> In article >,
>> "Jerry" > wrote:
>>
>> > Go to a local hobby store and get 'hot fuel proof clear dope"
>> >
>> > Jerry in NC
>> >
>> > "jt" > wrote in message
>> > ...
>> > > Got a pair of fuel-level senders and the cork floats have lost some of
>> > > whatever it was that was painted on them. These will be in tanks with
>> > > automotive gasoline. What should I use to seal them?
>> > >
>> > >
>> >
>>
>> I believe that the original treatment was shellac.
>
>I don't know if there is enough alcohol in your auto gas, but alcohol
>is a solvent for shellac.
>
>Ed Sullivan


Ed,

I have used "Indian Head" gasket shellac with good results in the
past. Whatever sealant is used, it should be tested prior to
installation on the airplane. Buy a bottle of decent wine and drink
it. When the cork is dry (yes, you must buy a wine with a real cork
in the bottle) coat it with the sealant to be considered and submerge
it, after curing, in the fuel to be used and watch it for a week or
more before deciding.

O-ring

Capt. Doug
July 16th 03, 02:54 AM
>Veeduber wrote in message . If you use it on a riveted
> aluminum tank, it works best if the tank is first etched with a mild
solution
> of phosphoric acid

I have a steel tank that leaves a bit of rust in the filter. Will sloshing
the tank solve the rust problem? If so, what compound do you recommend for
steel and should it be etched with anything beforehand?

D.

Del Rawlins
July 16th 03, 04:48 AM
On 15 Jul 2003 05:54 PM, Capt. Doug posted the following:

> I have a steel tank that leaves a bit of rust in the filter. Will
> sloshing the tank solve the rust problem? If so, what compound do you
> recommend for steel and should it be etched with anything beforehand?

Try this:

http://www.eastwoodco.com/aspfiles/itemdy00.asp?UID=2003071523462854&
T1=10165+Z&Dep_Key1=

I used a similar product to etch/seal the tank for my three wheeler (atv)
and have been very happy with the results.

----------------------------------------------------
Del Rawlins-
Remove _kills_spammers_ to reply via email.
Unofficial Bearhawk FAQ website:
http://www.rawlinsbrothers.org/bhfaq/

Veeduber
July 16th 03, 05:29 AM
>
>I have a steel tank that leaves a bit of rust in the filter.

------------------------------------------------

Dear Doug,

Rusy in your filters is good evidence it's time to clean & slosh the fuel tank.
The hazard here is two-fold; the most obvious is that your tank is generating
a contaminant that can lead to an engine stoppage. But the less obvious
problem is actually the more serious: Your fuel tank is dissolving. It will
eventually begin to leak.

-------------------------------------------------


>Will sloshing
>the tank solve the rust problem?

-------------------------------------------

No. In fact, it could make things worse. Sloshing will encapsulate the rust
but won't stop it. But when you apply selant over rust, even the
self-neutralizing crap -- PQR or whatever -- there's no guarantee the rust
won't flake or spall. That destroys the sealant and usually gives you some
industrial-grade contaminants to deal with.
You need to deal with the rust first, then seal the metal with a sloshing
compound that is impervious to gasoline.

------------------------------------------------

> If so, what compound do you recommend for
>steel and should it be etched with anything beforehand?
>
>D.
--------------------------------------------------

Compared to some of the more expensive polysulfide-based sealants, I've had
better results from PVA. This is on tanks I've made myself out of steel (for
vehicles) and aluminum, both riveted and welded, and from fiberglas. I ended
up with leak-free tanks and taught me how little I know about tanks, in that
there are myriad details specific to each type of tankage that must be
addressed. For that reason I'm reluctant to make a recommendation for
something that would be applied to another person's work. Not saying mine is
better but that it's impossible to know the details of the construction.

No matter what you use as your sealant, its durability is largely a function of
prepping the surface. With a steel tank you need to get rid of all rust,
repair any leaks then neutralize whatever acid you've used to get rid of the
rust, then get rid of the neutralizer and then dry the tank. A haze of rust
will form on any steel tank as soon as it's etched & dried but it doesn't
appear to affect the bonding of the sealant nor its durability.

Sulphuric acid is less expensive than phosphoric but it's chemical composition
appears to promote faster rusting than does phosphoric. (I'm talking minutes
here, as in the time between one step and the next.)

If if you've no experience with tankage or radiatiors you'd best stick with
phosphoric. In fact, if you've never done this sort of thing before I would
probably be best to start with something like a rusty oil drum. Or even
de-rusting some metal coupons using acid. Or best of all, having someone else
do the work. Radiator shops are your best bet but there's lots of welding
shops that specialize in tankage. They know all about acid etching,
neutralizing and sealing.

Since you're flying with an iron fuel tank I'll assume it's fairly small,
possibly in a T2 or similar airframe, in which case the wisest option may be to
simply frabricate a new tank, except this time out of riveted aluminum rather
than riveted & soldered galvanized sheet.

-R.S.Hoover

Peter Dohm
July 16th 03, 03:14 PM
Larry Smith wrote:
>
> Orval equivocated:
>
> > I believe that the original treatment was shellac.
> >
> >
>
> That was in them old glory days when gasoline did not contain volatile
> additives.

Especially alcohol, from what I read in a recent thread in this gorup.

Peter

Pat Thronson
July 16th 03, 10:44 PM
Now this is on a much larger scale here I know, but the principle is still
the same. Some of the fuel tanks I inspect API 653, are only coated approx.
5 feet up the sides, to protect from water attack, the rest of the tank on a
floating roof style is typically not painted.
For the (3) 2.8 MMG million gallon Jet-A tank project I worked on for the
Honolulu Airport, we painted all surfaces with mil spec. 2 coat epoxy
system, as this was their cleanliness requirement. Moisture is the enemy
here, fuel will not corrode the steel.

Pat Thronson CWI NACE

Eugenio Grapa
July 18th 03, 10:51 PM
snip ...

>
> I used light fibreglass cloth and polyester resin seven years ago,
> and it still floats. Didn't want to use resin alone, since it might
> chip off and plug things up.
> Dan

Use two component epoxy paint (usually for coating the inside of ..... the
tank) can be had at your web/local restore shop.

Eugenio

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