Gas Line question
10-16-2006 | 04:43 PM
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From: Rogers, AR
Gas Line question
I have an O.S. MAX FS .61 engine set up in a test bench. The first time I tried to start it turned over on the second slap of the prop. Ran great! I shut it off. Made some carb adjustments and tried to start. Nothing! Notice that when I opened the card just a little bit that the gas would drain back down the tube into the tank. So, I close the carb, pressurize the line and quickly opened the carb and started the engine. Is this normal? You can see the bubbles and the gas drain back each time I try to start it. Thanks for any help.
10-16-2006 | 04:52 PM
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From: Quinlan,
TX
RE: Gas Line question
Rugerfly,
It sounds like you have the tank mounted too far below the level of the carb. The best position for the tank is to have the tank centerline slightly below the centerline of the carb. With a full tank, this will put a little pressure in the fuel line prior to start. With this set up, if you try to start ther engine with the tank below one half full, the fuel will drain back into the tank when there is no suction draw from the engine. Usually you can get the engine started this way, but you must have a good prime to allow the engine to run long enough to draw fuel back up the fuel line to the carb. It's always best to use a full tank to allow the fuel to flow naturally to the carb for starting. Hope this helps.
PMW
It sounds like you have the tank mounted too far below the level of the carb. The best position for the tank is to have the tank centerline slightly below the centerline of the carb. With a full tank, this will put a little pressure in the fuel line prior to start. With this set up, if you try to start ther engine with the tank below one half full, the fuel will drain back into the tank when there is no suction draw from the engine. Usually you can get the engine started this way, but you must have a good prime to allow the engine to run long enough to draw fuel back up the fuel line to the carb. It's always best to use a full tank to allow the fuel to flow naturally to the carb for starting. Hope this helps.
PMW
10-16-2006 | 06:43 PM
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From: Corona, CA
RE: Gas Line question
Did anyone mention the tank below the carb thing yet?
Oh, never mind. (BTW, you guys are all within, like 2 minutes of each-other..NOW THAT'S SERVICE!!).
Oh, never mind. (BTW, you guys are all within, like 2 minutes of each-other..NOW THAT'S SERVICE!!).
10-16-2006 | 08:03 PM
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From: Phoenix,
AZ
RE: Gas Line question
Another possibility would be a vacum in the tank from inproper fuel line setup. I just recently switched one of my engines into a new plane. I was having problems and noticed that everytime the engine quit or the starter was removed, fuel would run back into the tank. Turned out my pressure lines were not hooked up right. It would always run fine for about 30 seconds before it quit. Just a thought
Cameron
Cameron
