Sealant for polyethylene fuel tank?

"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

They make sealed end pop rivets. Use them to sandwich some pro-seal between
the tank and an aluminum plate. Tap the plate for the fitting.

The old time fix is to rub the leak with a bar of soap. Seals the leak and
gas won't dissolve it.


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

Polyethylene is pretty hard to glue anything to.


LEAF has several sizes of rubber "plugs" that a barbed brass fitting
can fit into. Drill a hole, press in the rubber plug, and poke the
fitting into that.

IIRC, I used 1/4" on my plane, but I think they have a 3/8" also.

Other than that?

New Tank?

Richard

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

"TerryJ" suptjudatcomcastdotnet wrote in message
. ..
Teflon tape from ACE hardware....

"Rob Turk" wrote in message
. ..
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

Tried that, but it appears to be eaten by the ethanol additives from Mogas.

Rob

"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

On Mar 3, 2:32 am, "Rob Turk" wrote:
"TerryJ" suptjudatcomcastdotnet wrote in message

. ..

Teflon tape from ACE hardware....

"Rob Turk" wrote in message
...
I'm looking for a sealant or kit to seal brass NPT inserts into a
polyethylene tank. This is aKitfoxheader 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

Tried that, but it appears to be eaten by the ethanol additives from Mogas.

Rob

There is only one thing that will work that I have tried other than
plastic welding.
Get a stick of the 2 part epoxy for fuel tanks.
Knead together, and wrap around the thread then screw in the fitting.
Once in make sure you always hold a wrench on it when you are screwing
other fittings into it or it might break the seal.

Mine has not leaked in over 3 years now.

More Kitfox info and movies and GPS plotting stuff here http://www.cfisher.com


Dave

On Sat, 3 Mar 2007 08:36:23 +0100, "Rob Turk"
wrote:

"cavelamb himself" wrote in message
ink.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

Can you hog it out to the next size pipe thread and put a reducer
bushing in? Make sure you use a tapered pipe thread and do not
overtighten it. Make sure you use FLEXIBLE line from the tank to the
fuselage. Rigid tubing WILL eventually take the threts out of the poly
tank.

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