stunthanger.com
Engine basics => Engine set up tips => Topic started by: frank mccune on October 17, 2013, 03:13:07 PM
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Hi:
I sould like to see some pictures of a Aullivan plastic tank set up for uniflow.
I fabricated some thirty years ago but if I remember correctly, the fuel pick dragged on the side of the tank and did not reach into the extreme corners of the tank. Is this normal?
Tia,
Frank
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Here's a sketch of one that I recently made. The vent tube's not shown correctly.
The idea is that the uniflow goes in the right spot, and the clunk kind of reaches over it to get to the wall of the tank.
Mine gives a perfect, steady run until the engine runs out of fuel and stops without muss or fuss.
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Attached is a picture from a SN article by Nils Norling. The fixed uniflow tube Tim shows has the advantage that you can adjust the tube position vs. adjusting the entire tank to equalize upright/inverted lap times. I think I'd position the fixed tube farther forward, to prevent potential fouling the pickup clunk line. H^^ Steve
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You can also choose to solder a short piece of tubing to the outside of the clunk and run fuel line to the clunk and added tube.
I don't know what the clunks are coated in but solder sticks super easy to it.
Phil
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You can also choose to solder a short piece of tubing to the outside of the clunk and run fuel line to the clunk and added tube.
I don't know what the clunks are coated in but solder sticks super easy to it.
Phil
Most are bare brass, or plated. The "dual" system where both tubes go to the clunk are a problem sometimes because you have the same mass, but two tubes to bend. I like the hard vent system better.
Brett
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I have had good luck with the John Miller uniflow setup. Details and diagrams can be found via a search on this site or the other one. Try "John Miller Uniflow Tank Setup". 8)
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Here's a sketch of one that I recently made. The vent tube's not shown correctly.
The idea is that the uniflow goes in the right spot, and the clunk kind of reaches over it to get to the wall of the tank.
Mine gives a perfect, steady run until the engine runs out of fuel and stops without muss or fuss.
I just set one up like Tim's. What is the best way to fuel it, pull the tube from the muffler and fill through the uniflow vent?
Also should I put a check valve in the pressure line?
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Pull the stopper off of the vent, pull off the pressure tube, and fill through the uniflow. Sometimes it's easier to pull the pressure line at the muffler, sometimes at the tank.
Don't forget to put the vent plug back on when you've fueled it up.
You don't need a check valve -- on the outside of the tank, aim the uniflow line up so that the loop of tubing to the muffler can't form a siphon. Or never leave the thing fueled and waiting unattended.
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Thanks, Tim.