wsmalley

My Feedback: (6)

I was reading a post the other day-which of course now I can't find- where the author said something about "if you are not using a burp tank,..................." Wondering what it is. I guessed maybe a header tank used primarily, I think, in DF setups. Curious if I'm missing something in my fuel tank set-ups of value.

jaka

Hi!
There isn't anything called a "burp tank" You probably think of a "Bubbleless " tank.
These tanks are made by Tettra company of Japan and have an inner bladder made of silicon where the the fuel is located.
Around it is an ordinary hard shell of plastic like an ordinary fuel tank.

You fill the inner bladder with fuel as with an ordinary tank using your electric fuel pump ..or a special mechanical pump made by JETT enginering in Texas. These tanks are mandatory in pylonracing and are used world wide by us pylon guys.
These tanks are expensive but are well worth the money because they make our engines run more reliable.
Vibrations are no problems with these tanks as fuel and silencer pressure (air) is never mixed.
The pressure from the pipe/silencer compresses the inner silicon bladder and fuel is pressed to the ventury/carb. No clunk is used.
There are Tettra tanks from the smallest 85cc to a the largest 750cc tank

vicman

My Feedback: (10)

There is a method of filling B-less tanks that uses a burp tank. You use three lines like normal (exhaust pressure, fuel to carb, and filler). When fueling, the plane is held vertically with the fuel to carb line leading into a regular tank (burp tank) that is just loose and used while fueling. You then fuel it up using the filler line and watch the line heading into the burp tank until there are no bubbles coming thru. Apply hemostats to the ftc line and reconnect.
Can't really comment on the benifiet of this method, I just seen it done.

Charlie P.

Wonder if it has something to do with spillage. Boats are now being required in some marinas to affix an overflow bottle to the fuel tank vent so it can't spatter out into the water ($50,000 fine!) when the tank is completely full. Could it be some airfields are requiring the same. I always use the "squirt" out the vent to tell when I'm fueled up. That's a lot of spillage multiplied by hundreds of thousands of fliers nationwide. A catch bottle would prevent that.

Just a thought.

wsmalley

My Feedback: (6)

Learn something every day! I had not heard of the Tettra tank but can see some advantages there. I have also seen some guys use a tank to catch overflow which I guess is more important if you're using an electric pump. Personally, I just fill 'til it drips out the exhaust, I use the old fashined hand crank, don't think it amounts to a half a teaspoon. At $14 a gal., I try to watch it closely!

vicman

My Feedback: (10)

The use on the b-less tank is to make sure that there are no bubbles in the tank. Using the Jett pump jaka mentioned you would suck the bladder dry and then refil the bladder with fuel. Both methods keep air out of the tank. With the pump you will get more fuel into the tank since you are squeezing the air in the tank out thru the exaust inlet line thus the tank is almost pressurized.
Bob27 can comment more in detail or you can go to the Jett site.