Sealant for polyethylene fuel tank?

On Thu, 01 Mar 2007 20:37:38 GMT, Dennis Fetters
wrote:

wrote:
On Mar 1, 12:55 am, "Rob Turk" wrote:

I'm looking for a sealant or kit to seal brass NPT inserts into a
polyethylene tank. This is a Kitfox header tank that has developed a leak at
one of the inserts. I'm probably going to use Mogas that has ethanol
additives. Any hints, tips, thoughts?

Thanks,
Rob

Red high temperature silicon sealer. Local hardware store. Clean the
threads with alcohol and apply sealer. Lasts forever.


Except RTV is NOT gasoline resistant.

--
Posted via a free Usenet account from http://www.teranews.com

clare at snyder.on.ca wrote

Except RTV is NOT gasoline resistant.

Right.

How about some welding with a pencil torch, and some cut up strips of like
plastic?

The key is to keep the fitting hot enough so the strips of plastic stay
melted onto it, and cools and hardens after the heat is taken away, and
enough heat is also applied to the tank plastic and the strips so that they
toughly melt together.

It is a fine line, getting the tank hot enough to soften, but not melt
through.

The other option that comes to mind is a fitting that is a plate with
threads in it for the fuel line fitting, installed inside the tank and
another plate on the outside the tank, with a gasket on both sides, and
screws holding them all together. That could be done second, if the dreaded
melt-through happened around the fitting. This could be manufactured at
home, if one was a bit handy, and creative.
--
Jim in NC

Rob said his tank had developed a leak. That would mean that there had
been gasoline in the tank. I don't think anyone would suggest welding
a used metal tank, how could it be any safer with a plasic one?


Steve in Michigan

On Thu, 1 Mar 2007 22:30:32 -0500, "Morgans"
wrote:


clare at snyder.on.ca wrote

Except RTV is NOT gasoline resistant.

Right.

How about some welding with a pencil torch, and some cut up strips of like
plastic?

The key is to keep the fitting hot enough so the strips of plastic stay
melted onto it, and cools and hardens after the heat is taken away, and
enough heat is also applied to the tank plastic and the strips so that they
toughly melt together.

It is a fine line, getting the tank hot enough to soften, but not melt
through.

The other option that comes to mind is a fitting that is a plate with
threads in it for the fuel line fitting, installed inside the tank and
another plate on the outside the tank, with a gasket on both sides, and
screws holding them all together. That could be done second, if the dreaded
melt-through happened around the fitting. This could be manufactured at
home, if one was a bit handy, and creative.

"Earl" wrote in message
...
Rob said his tank had developed a leak. That would mean that there had
been gasoline in the tank. I don't think anyone would suggest welding
a used metal tank, how could it be any safer with a plasic one?


Steve in Michigan

You got it ;-) I like flying, but not *that* kind flight...

Rob

"Earl" wrote

Rob said his tank had developed a leak. That would mean that there had
been gasoline in the tank. I don't think anyone would suggest welding
a used metal tank, how could it be any safer with a plastic one?

Doh! I realized that, right after I hit send. I'm sure I would not have
done that if it were sitting there in front of me!

A soldering iron would be safe, and almost as effective at doing a little
plastic welding. It is kinda' fun, if you have ever done it before.
--
Jim in NC

On Mar 2, 12:18 pm, "Morgans" wrote:
"Earl" wrote

Rob said his tank had developed a leak. That would mean that there had
been gasoline in the tank. I don't think anyone would suggest welding
a used metal tank, how could it be any safer with a plastic one?

Doh! I realized that, right after I hit send. I'm sure I would not have
done that if it were sitting there in front of me!

When I said "welded" in my original reply I had.assumed thatmost would
take that as the "normal" method of welding plastic - with a plastic
welder that uses hot air.

Assumptions generaly BITE!

As for the idea of red silisone - don't. Been there done that. Gave
up the practice many years ago. No matter how small an amount you use
the gas wil eventually swell it up and leak through. A waste of time
and materials - IMHO

In article ,
Earl wrote:

Rob said his tank had developed a leak. That would mean that there had
been gasoline in the tank. I don't think anyone would suggest welding
a used metal tank, how could it be any safer with a plasic one?


Steve in Michigan

Actually, it is quite safe -- if done right. I have done this several
times.

1. Look up "Dry Ice" in your Yellow Pages.

2. Get the smallest amount they will sell you (usually about 5 lb.)

3. Put it in the tank and let sit for about 1/2 hour.

The dry ice (CO2 no thanks to Al Gore) displaces smothers the oxygen
from the tank and will not support combustion.

The nice thing about dry ice is that it leaves no residue, unlike
filling the tank with water

On Fri, 02 Mar 2007 20:51:21 GMT, Orval Fairbairn
wrote:

In article ,
Earl wrote:

Rob said his tank had developed a leak. That would mean that there had
been gasoline in the tank. I don't think anyone would suggest welding
a used metal tank, how could it be any safer with a plasic one?


Steve in Michigan

Actually, it is quite safe -- if done right. I have done this several
times.

1. Look up "Dry Ice" in your Yellow Pages.

2. Get the smallest amount they will sell you (usually about 5 lb.)

3. Put it in the tank and let sit for about 1/2 hour.

The dry ice (CO2 no thanks to Al Gore) displaces smothers the oxygen
from the tank and will not support combustion.

The nice thing about dry ice is that it leaves no residue, unlike
filling the tank with water

Welded (brazed) a patch on the oilpan of a '64 Riviera one day without
pulling it. Rinsed out all the oil I could, first with varsol, then
hot water - and filled the crankcase with a CO2 extinguisher. Had the
apprentice sitting on the fender, giving it a little shot every minute
or so untill I has the patch fully sweated on. (guy had driven into
the rebar used to spike a parking cub down and HAD to leave for
Chicago that evening - from Kitchener Ontario)

--
Posted via a free Usenet account from http://www.teranews.com

Orval Fairbairn wrote:

In article ,
Earl wrote:


Rob said his tank had developed a leak. That would mean that there had
been gasoline in the tank. I don't think anyone would suggest welding
a used metal tank, how could it be any safer with a plasic one?


Steve in Michigan


Actually, it is quite safe -- if done right. I have done this several
times.

1. Look up "Dry Ice" in your Yellow Pages.

2. Get the smallest amount they will sell you (usually about 5 lb.)

3. Put it in the tank and let sit for about 1/2 hour.

The dry ice (CO2 no thanks to Al Gore) displaces smothers the oxygen
from the tank and will not support combustion.

The nice thing about dry ice is that it leaves no residue, unlike
filling the tank with water

I've been using dry ice for a while now to extend the ice box on my
boat. One summer and the cooler is crazed, cracked, and nearly useless.

Wouldn't recommend this aproach on a plastic fuel tank.


I'm gonna stick with this one:
http://store.leadingedgeairfoils.com...th=548_436_568

Fuel Tank Bushing
SKU: H7285
$1.00

Richard

"cavelamb himself" wrote in message
nk.net...


I'm gonna stick with this one:
http://store.leadingedgeairfoils.com...th=548_436_568

Fuel Tank Bushing
SKU: H7285
$1.00

Richard

That looks pretty convincing. Someone else suggested Dapco, which has the
same plugs. I e-mailed Dapco and they confirmed their product to be good for
this, including being Ethanol resilient. They are an OEM supplier so I don't
think they will do small quantities, but I have not asked yet.

Rob