debspersonaldogwalker

Hi, I'm flying a Pica Jungmeister .60-size biplane powered with a Thunder Tiger .90 four stroke. Pica designed the airplane so an eight-ounce fuel tank just fits and it would be quite a rebuild of the fuselage to install a twelve-ounce tank, my choice for this engine.
Another tank would fit, however, farther back in the fuselage. I'm wondering if two tanks can operate as if they were a single tank. I'm thinking the pressure tube from the muffler would pressurize the rear tank. This tank would supply fuel to the front tank via a tube with a clunk in the rear tank. The front tank would supply the carburetor via a tube with a clunk in the front tank. So I'm wondering if the muffler pressure would be enough to push fuel from the rear tank to the front tank and also supply the carburetor with fuel from the front tank.
Otherwise I can simply program a five-minute alarm into the transmitter and not fly as long.
Thanks to anyone with experience with this kind of set up.

Warjet

My Feedback: (327)

Many years ago, I remember a posting from someone wanting to do the same thing, and a responder attached a picture of the setup he used. If you searched some threads it should still be there. If memory serves, it was pretty much like you said, but it seems he had to do something special when fueling, like fueling the back tank and letting that flow into the front and tying the 2 tank vents together.

Warjet

My Feedback: (327)

I found the link from 2003: http://www.rcuniverse.com/forum/m_10...tm.htm#1049404

JohnBuckner

My Feedback: (1)

Here is one of my current installations using four tanks in tandem with a total of 72 ounces and .illustrates the tandem plumbing.
Its a perfectly viable system regardless of the number of tanks and works well. This system is well proven on several long flights. I am currently working on another ship that will carry 128 ounces in three tanks.

In operation the tank that is last in line will be the first tank emptied and proceeds forward conversely when fueling the first tank in line (the one connected directly to the carb) will fill and proceed to the next in line untill all are filled.

John

debspersonaldogwalker

I'm fascinated by your floatplane. It must carry a big radio battery as well. How long are these long flights? Do you pilot from a moving boat? Please tell us about it :^D

JohnBuckner

My Feedback: (1)

Thanks, Here is a link to the thread on the river running airplane and this is a photo of the uncompleted Catalina Kadet:

http://www.rcuniverse.com/forum/m_11239869/tm.htm

Luft-Gangster

attached pic from Dave Platt P-51 from back in 82.

debspersonaldogwalker

Gentlemen, you've been most helpful!

TFF

I forget the size I used but it was at least 10oz but I think it was a 12. I used one of the Sullivan flex tanks. Stock fuselage. Run time was ok. At a contest the throttle arm fell off and I had to fly for 15 min after doing the sequence. Mine has a Magnum 91 4 stroke. It has been flying for 10 years.

BillS

I have used dual tanks many times, usually a large tank and a smaller header tank close to the engine. John in post #4 shows the method of plumbing. At full throttle the pressure head will be from 10" to 16" of water or about 1/2 psi. On twins the large tanks were in the fuselage and the header tanks were at the engine. The fuel line between main and header tank was sometimes 25" or so. However you cannot feed two engines with one fuselage tank.


Bill