Fuel Tank Sloshing

[blueshed]

would some kind persons be able to assist with information on RE Sloshing of aircraft fuel tanks.

 

Like, does it have to be the same compound as original, or are they compatable?

 

Where does one purchase these products?

 

How much does one need?

 

Can the tanks be resloshed as is? or does the fibre glass need to have external repairs done first? They leak a little! The wing has a tubular spar which the wing sections are attached to, each being glued to the next, thus creating tanks.

 

Thanks Guy

 

 

[Guest browng]

I too would be interested in any info on this. In my case I have a small crack near the top of one of my Jodel 27ltr wing tanks that prevents the last 5lts being put in. The tanks are aluminium though, not fiberglass.

 

 

[facthunter]

Tanks

 

browng, Just reweld it if it's aluminium, as any kind of liner is SUS. especially with the substances they call petrol these days. clean all trace of fuel out first, and fill with an inert gas, prior to welding. N...

 

 

[Guest browng]

browng, Just reweld it if it's aluminium, as any kind of liner is SUS. especially with the substances they call petrol these days. clean all trace of fuel out first, and fill with an inert gas, prior to welding. N...

Yes, welding is the best option, but I was hoping to avoid stripping the fabric off the wing. Given that I have two 27ltr wing tanks and a 60ltr nose tank, I would probably just accept the loss of 5lts in capacity rather than having to strip the wing.

 

 

[Guest Teenie2]

Spruce sell sloshing compound which is compatible with modern fuels.Another option is motorcycle shops, they use the compound on rusty tanks.You could also use fuel tank sealant (pro-seal)and repair from the outside.

 

Good luck finding a welding shop to weld a fuel tank (workcover regulations) at a reasonable price.

 

 

[brilin_air]

If you really have to weld a fuel tank, fill it with water first, it shouldn't be a problem then to weld it with the water in it, drain it after the job and slosh some methylated spirits in the tank to remove water residue, drain it and let it dry.

 

You might have a problem getting people to weld a tank that has been used as they all get nervous about this type of job.

 

Brian

 

 

[trevorp]

browng, i would fix leak in tank asap because the fuel slosh and fumes leak's could cause more damage too more than eye can see. TP

 

 

[Guest browng]

browng, i would fix leak in tank asap because the fuel slosh and fumes leak's could cause more damage too more than eye can see. TP

There is no leak if its not filled to the last 5lts, and even when it is, its only a steady drip. It's just not worth the effort of pulling the fabric off when I have over 5hrs endurance anyway.

 

 

[facthunter]

Tank repair.

 

Just a comment or 2, water can affect the weld. It would be somewhat difficult to get someone to do a repair to it after the fuel has been in it , as they get a bit jittery. One way over that is to do it yourself. Argon welding of Al sheet is easy. Just practice on a slightly thinner sheet for a while first, and weld away from draughts (air).

 

To prepare the tank, be sure to remove ALL fuel first, then slosh with avgas to dissolve all the remaining car fuel,(Be generous as this can be used later). Empty and blow out with air, to remove remaining fuel. Avgas easily evaporates leaving no residue. Leave in the sun and check no smell.

 

Purge tank with nitrogen,or CO2,( some use a car exhaust, but it's not as satisfactory, as it may have some C0) and proceed to weld.

 

I wouldnt operate the aircraft with a crack in the tank as in rough air there is the possibility of a leak. Mogas has a bad effect on your brain, when the fumes are inhaled.

 

There's a plastic substance which I have seen used to repair aluminium radiators which I am sure will give a good temporary in- situ repair ,if you have access to the tank. A small patch could be applied by this means as well.. Nev

 

 

[Guest browng]

Just a comment or 2, water can affect the weld. It would be somewhat difficult to get someone to do a repair to it after the fuel has been in it , as they get a bit jittery. One way over that is to do it yourself. Argon welding of Al sheet is easy. Just practice on a slightly thinner sheet for a while first, and weld away from draughts (air).To prepare the tank, be sure to remove ALL fuel first, then slosh with avgas to dissolve all the remaining car fuel,(Be generous as this can be used later). Empty and blow out with air, to remove remaining fuel. Avgas easily evaporates leaving no residue. Leave in the sun and check no smell.

Purge tank with nitrogen,or CO2,( some use a car exhaust, but it's not as satisfactory, as it may have some C0) and proceed to weld.

 

I wouldnt operate the aircraft with a crack in the tank as in rough air there is the possibility of a leak. Mogas has a bad effect on your brain, when the fumes are inhaled.

 

There's a plastic substance which I have seen used to repair aluminium radiators which I am sure will give a good temporary in- situ repair ,if you have access to the tank. A small patch could be applied by this means as well.. Nev

Agreed, however in my case (a) I run AVGAS, (b) it is a wing tank external to the cockpit, and © if I don't put in the last 5lts there is no leak whatsoever. The previous owner has operated the aircraft in this manner for 7 years without problems.

 

 

[facthunter]

Leak.

 

Fine.....N...

 

 

[Guest Teenie2]

If you do not want to remove the tank use pro seal and repair it from the outside(if you can see the crack) This is how Boeing ,airbus and most of the large A/C seal the tanks.Rivet the alloy together then coat the inside with sealant and sometimes the outside.Yes it will handle auto and Av gas no probs,this is how most US experimental alloy tanks are done. see http://www.aircraftspruce.com/menus/ap/fuel_tanksealants.html

 

You don't need to buy the gun just use a hammer handle to push the sealant through.

 

 

[wanabigaplane]

Sloshing compound

 

Had great success with fibreglass wing tank in my Sapphire which leaked internally to the wing on purchase. Used 3m EC-776 "Fuel Resistant Coating"

 

It even blocked the air inlet tube.

 

Horrible stuff. Depends on evaporation of solvents to cure. I blew air into the tank for days until the smell was minimal.

 

On inquiry the 3m rep sent me a sample. The sample was 1 quart which was twice what I needed to do the job !

 

Jack. :)

 

 

[blueshed]

Thanks Guy's

 

Tar for all the info, checked out the 3m ec776, found somewhere it is the same as 3m 776, just that 3m ec776 is certified for aircraft!

 

wanabigaplane (Jack), did you remove your tank and put it on the inside? Spray, brush or fill the tank and tumble the tank?

 

Thanx everybody

 

Cheers Guy

 

 

[wanabigaplane]

slosh slosh

 

The tanks in the Sapphire wing are wet wing tanks. I swilled the tank out with raw petrol first, then one wash with acetone, then blew air in for a day. I don't know if this was necessary, but since the tank is normally filled with a two stroke mix, I was concerned with adhesion. I suspended the wing at one end from a high point by rope, tipped the stuff in, and rotated the wing the wing in all directions for a time that I guessed would far exceed the healing time. I also had a small compressor blowing air into the tank all the time, and for about three days afterwards. The stuff had a consistency of and looked like honey, and has a very potent smell similar to acetone.

 

Waving a Sapphire wing around takes up a lot of space, but the fumes alone would cause you to want to do it outside anyway.

 

PS - See you are at Jamestown. I dropped in there once a few years ago. Caught up with Tony Witlox there on our trip around Australia in Sapphires.

 

Jack.:yuk::;)6::;)2: