Help! Fuel system on twin
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Help! Fuel system on twin
Ok I have two O.S. 46 fx's and here is how I have my fuel system set up...I have a 24 oz fuel tank, I have two clunks in the tank with two pick-up lines, one going to the left engine and one going to the right engine. I only have one preasure line leaving the tank and then have a T splitter with one line going left and the other right. I have this problem when I am only running one engine, the opposite engine starts to get flooded with fuel. I am guessing the preasure from the operating engine is pushing fuel to the dead engine?? If anyone knows what I could do to prevent this please let me know! Thanks so much!
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RE: Help! Fuel system on twin
Been there, done that, didn’t work. My engines did not flood but they could not be tuned to run with the same top end they had before change.
I would and have simply put two 12oz tanks in the center to isolate the two systems. More complex solutions exist which I have not tried.
Bill
To complicate matters an 8oz tank is usually adequate for a 46 and 12oz will sometimes create fuel draw problems in a single engine application.
I would and have simply put two 12oz tanks in the center to isolate the two systems. More complex solutions exist which I have not tried.
Bill
To complicate matters an 8oz tank is usually adequate for a 46 and 12oz will sometimes create fuel draw problems in a single engine application.
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RE: Help! Fuel system on twin
ok, this is what worked for me, i simply put a tank for each engine and ran the fuel lines as short as possible, avoid inverted engines at all cost, you can make them run right but they are not as reliable as if they where mounted up right!!
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RE: Help! Fuel system on twin
You might want to check out out this system. I just heard about it and it looks interesting. besides allowing you to put the tank on the CG, it enables you to run two glow engines off of one tank.
http://www.billsroom.com/pcfs/
http://www.billsroom.com/pcfs/
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RE: Help! Fuel system on twin
[b]captnem:
You started out correctly, using a single tank with separate clunks for each engine. From that point though, it's almost impossible to get satisfactory results with an ordinary muffler pressure system.
My way is a Perry VP-30 pump on each engine, although the Cline (or Iron Bay) regulators will also work, as suggested by Tmoth4.
Final note - the Perry system costs about 1/2 the price of using Cline or Iron Bay.
Bill.
You started out correctly, using a single tank with separate clunks for each engine. From that point though, it's almost impossible to get satisfactory results with an ordinary muffler pressure system.
My way is a Perry VP-30 pump on each engine, although the Cline (or Iron Bay) regulators will also work, as suggested by Tmoth4.
Final note - the Perry system costs about 1/2 the price of using Cline or Iron Bay.
Bill.
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RE: Help! Fuel system on twin
I have successfully used the Cline regulators in a single tank setup on a Me110. One item of note: the Cline regulators do not provide a pressure feed to the carburetor. They work so as to make the carb act as if it is drawing fuel from a distance equal to the distance from the regulator to the carb. In order to make my engines (Thunder Tiger .46) run reliably without pressure at the carb, I had to put restrictors made of brass tubing in the carb throats to increase the suction draw.
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RE: Help! Fuel system on twin
One very simple thing you can try is to just vent the tank out the bottom of the fuselage. Do not hook up vent to either muffler fitting. Most sport engines run just fine this way. You will probably need to adjust the mixtures a bit. You can tell how much pressure attaching the vent to your muffler produces by the size of the mixture change required to run without it. I have seen home made mufflers for scale planes with a "pressure" fitting installed that is actually causing suction.
Multiflyer
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RE: Help! Fuel system on twin
Hi captnem,
If you go to one of my older posts in my moments of insanity at http://www.rcuniverse.com/forum/m_24...tm.htm#2447788 You will find exactly the answer to this question,,,except I need four engines on one tank.
Hope this helps.
Twinman
If you go to one of my older posts in my moments of insanity at http://www.rcuniverse.com/forum/m_24...tm.htm#2447788 You will find exactly the answer to this question,,,except I need four engines on one tank.
Hope this helps.
Twinman