Finger strainers, looking for advice

[Guest]

Re: Finger strainers, looking for advice

For a long time I got clogged wing tank drain valves. It was after I had mistakenly put auto fuel with alcohol in.

The alcohol softened the sloshing compound and it slowly accumulated at the drain valve clogging it every 8-10 months for years. (I suppose the prior owner could have used the wrong or bad sloshing compound that may be a better explanation)

During that period I started looking in the filler openings with a penlight sized flashlight. Main tank is easy and if you look when outside lighting is dark or dim you can see thru the fuel even if tank is full.

Wing tanks require looking at an angle to see the rear corner and there is no fuel in them when I look.

One or two years I saw debris and made a rubber and metal tube extension for my vacuum cleaner that could get thru the filler caps. Dry out the tanks before trying this.

Dave.

[Hank Jarrett]

Re: Finger strainers, looking for advice

Be VERY careful when using a vacuum to clean teh inside of a fuel tank. Even when it has been well ventilated for a LONG time there can still be fuel vapors that can ignite when the air is pulled through the vacuum motor! If you can get a vacuum that works on compressed air instead of an electric motor you will be a LOT safer. They work on a Venturi effect, you also DO NOT want to be blowing air IN TO the tank to clean it out.

Hank

[PA1195]

Re: Finger strainers, looking for advice

I might add that the process of draining the fuel tank requires precautions and a suitable fire extinguisher handy. I bond the tank metal to a positive ground nearby (like a screw anchor tiedown rod) with wire, and use a conductive filter funnel (http://www.mrfunnel.com/Mr._Funnel/Home.html) and empty metal fuel container supported by an aluminum ladder also bonded to the grounding wire system. I try to keep every component at an equal state of electrical charge.

I know of one incident where the draining of a fuel tank resulted in a fire. A friend/PA-18 owner was draining one of his wing tanks into a can on the ground (with unbonded airframe) and some spillage ignited via static electricity. He pushed the plane away from the initial fire but the still draining tank fed the fire which followed him and eventually consumed the wing.

This is a drift from the OP's initial post but does relate to dealing with fuel tank components to some degree.

Gary

[Guest]

Re: Finger strainers, looking for advice

Be VERY careful when using a vacuum to clean teh inside of a fuel tank. Even when it has been well ventilated for a LONG time there can still be fuel vapors that can ignite when the air is pulled through the vacuum motor! If you can get a vacuum that works on compressed air instead of an electric motor you will be a LOT safer. They work on a Venturi effect, you also DO NOT want to be blowing air IN TO the tank to clean it out.

Hank

Good idea

[Robert Lees]

Re: Finger strainers, looking for advice

I use a small domestic steam cleaner to vent fuel vapours from a tank for welding.

Low pressure, high heat, lots of steam all for about 4 hours and there are no more avgas vapours there.

[astjp2]

Re: Finger strainers, looking for advice

I had one of those blow up on me from the static electricity. You need to displace the oxygen, use something like argon or CO2. Just don't pressurize the tank doing it, just a slow trickle will do it. Tim

Good idea

[PA1195]

Re: Finger strainers, looking for advice

I had an aircraft fuel tank that needed a fitting added (non-compliant with STC). Took it to a radiator repair shop and they put it in or used whatever device they use to clean radiators before repair.

Gary

[Guest]

Re: Finger strainers, looking for advice

I had one of those blow up on me from the static electricity. You need to displace the oxygen, use something like argon or CO2. Just don't pressurize the tank doing it, just a slow trickle will do it. Tim

doh! good point

Didn't think about that, air flow and vinyl tube could make discharge!

I keep my wing tanks dry most of the time so I have few issues with fuel fumes.