GRRR to Great planes on this one...


I've recently bought a Venus 40 and I've jammed an enya 50 (soon to have a 60 so i can go silly) but the problem is the tank position...They've sent the tank up so that it's in line with the crank, and it's an inverted motor.

Stupid stupid stupid.

I'm now stuck with a virtually unmanagable engine because the tank's too high.

I' can't lower it becuase the distance between the firewall and the mounts for the wing dowels is 100mm (4") and the tank is about 5" all up...

What do I do? This is a real pain in the backside ( or "Date" as downunder and i know it as)Will a header tank fix it? Do I need to make my own custom tank???This makes a nice aeroplane frightening to fly cos it dead sticks and changes needle setting something shocking as the tank drains..

Hi
I thought about two methods because of this solution of a problem. The first is to exchange it for the tank included in that space frankly.
In this case, tank capacity will be a little small.
The second is to put a pump which can stop fuel.

I will endure it by the first.
kobayan

I've thought about running two smaller tanks (say 4oz side by side because they'll fit in, but it seems a lot of crapolla for little gain...

A pump would be an expensive excercise, any other low cost ideas?

It is how if the tank of standard isn't used and a container of the soft drink is used.
It looked like a soft container for the intravenous drip.
It is a thing to see well in Japan.
kobayan

I'm guessing you mean the centre of the tank is in line with the crankshaft. Is it possible to side mount the engine? That'll raise the carb level to be centred on the tank.

Just curious, but will you be going to the Enya 60 later? That's one ripper of an engine

I just thought of something you could try. Reroute the vent line so that it ends at the bottom of the tank instead of at the top. This will probably mean using a different fill method but that's an easy fix. You'll need to retune your engine (it'll need to be richened a little) because now no matter how much fuel is in the tank the engine will think it's almost empty while that vent is covered with fuel. When you go inverted the vent line will be uncovered and then the mixture will feel the amount of fuel but because the tank (when inverted) is a bit low it should balance out quite well.

For those that are thinking "what the????"...it'a variation on the uniflow tank priciple. All normal RC clunk tanks become a uniflow when you fly inverted (the vent is then at the "bottom" of the tank) and the engine tends to lean out a little. This is just making it work the other way round.

I'm wondering what others did with this problem..Most ARF's are pretty well thought out and a tank in the wrong position would be a problem to everyone that buys the plane.
Is the plane put together so you can try to run the engine and see what happens.Would using a smaller engine put it in the rite place?I realize you want a bigger engine (I would too) but is the plane built for a certain size power plant. I had to do some fanagaling putting a 61 SF in a 40 size Cloud Dancer.I have two planes with inverted engines and they both look great but do have to be handled differently.It's a slight chore making sure you get rid of all the fuel at the end of the day that's in the head.I've bought a few extra plugs til' I learned how to get rid of all the fuel in the engine.Just my two cents...Walt

Q-ball, the biggest problem, as downunder knows, is the changing head and siphon effect of having to high a tank position..

It just pisses out of carbie if it's open just a crack.

Need to investigate this uniflow tank stuff downuder, could be a winner or it could cover my model in raw fuel!

When in doubt, i'll just fit a pacifier to it!

BTW O.S. 61 sf, grrrrrrowl!

I'm curious what people think would happen if a pump like a Perry V30 was used. http://www.perrypumps.com/prod02.htm

I have a plane setup (not yet flown) where the tank can be placed in the usual position. Alternatively, I can (and will) put it back over the CG and use the V30 pump. But when back over the CG the bottom of the tank is in line with the carburetor.

When placed over the CG, the tank is higher than normal, but with the pump I expect that I will be able to tune the engine with the tank full, then as it drains (static pressure drops) the pump will make up the difference. Same goes for when the plane flips upside down.

Anyone ever tried something like this?

The plane happens to be a Great Planes Tracer. You can squeeze the tank in under the canopy. That's just a tad in front of the CG. The pump fits nicely between the engine and firewall.
The engine mounted at roughly 45 degrees - that raises the carb just enough to line up with the bottom of the tank.

I'm working on a Phenix PH011 .55 Powered Corsair. The Manufacturer (Phoenix) says to mount the engine at about 120 Degrees Counter Clockwise from Vertical so the Muffler is at the bottom. Phoenix suggests and designed the Fuel Tank be mounted on a flat piece of lite plywood above the height of the Carburetor for the typically installed Inverted Engine. It's at least 1.25 Inches above the Spray Bar of the Semi-Inverted Carburetor. So this is going to cause problems when I have the tank full and I'm waiting to fly because the fuel will syphon out of the Spray Bar. I thought I would cut out the original Tank Floor, Cut the Mid Horizontal sections of two Fuselage Formers, and lower the Tank about 1.25 Inches on top of the remaining portions of the two Fuselage Formers. The Tank would also need to move backward from the Firewall about 2.5 Inches because the tapered Muffler Cavity was built into the lower portion of the Fuselage. I don't think the extra 2.5 Inches should hurt the Fuel Flow while using Muffler Pressure with the two-line Tank Set-up. Let me know if anyone thinks I'm wrong. I'll include an Illustration showing where the existing Fuel Tank Floor is and the Former Horizontal Sections I intend to cut out.

I'm contemplating moving the Phoenix Placed Fuel Tank Floor so it fits on top of the lower two Formers you see in this illustration. I need to move the tank rearward about 2.5" because the Muffler Box is below the Forward portion of the existing Fuel Tank Floor. So the rear of the tank will be about even with the forward edge of the Gray Wing Joiner Tube shown in the photo.