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Old 04-01-2009, 09:02 PM   #1
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Default Why wont it suck?

Hi

My engine wont suck fuel from the fuel tank when I try to prime it. The fuel lines havent got any holes in them because Ive tried other fuel lines and theyre not blocked. What could it be? Any ideas welcome
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Old 04-01-2009, 09:04 PM   #2
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Originally Posted by Silencedsteak View Post
Hi

My engine wont suck fuel from the fuel tank when I try to prime it. The fuel lines havent got any holes in them because Ive tried other fuel lines and theyre not blocked. What could it be? Any ideas welcome

High speed needle is clogged....take the needle off and make sure everything is clear and no gummy fuel is preventing a prime.
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Old 04-01-2009, 09:05 PM   #3
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Default Pressure line?

What about the pressure line from the muffler? Have you checked it for leaks?
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Old 04-01-2009, 09:14 PM   #4
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Maybe there's an issue with your fuel tank/lid isn't sealing right, or your tank is cracked.
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Old 04-01-2009, 09:17 PM   #5
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is there still compression no compression no sucky sucky
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Old 04-01-2009, 09:29 PM   #6
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No leakes in the pressure line. Tank not cracked. needle not clogged. There is compression.
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Old 04-01-2009, 09:34 PM   #7
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how are you priming it?
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Old 04-01-2009, 09:39 PM   #8
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It works again. Just turned it over for about 40 seconds with my finger plugging the exaust and all of a sudden fuel started to go into the carborator. Thanks for all the help
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Old 04-01-2009, 09:39 PM   #9
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Stupid question,
Have you tried plugging the exhaust as you crank the engine over. If so there is most likely a blockage some where. Fuel filter, carb, fuel line, pressure line, etc. Also if either needle is screwed in to far it would shut off fuel flow (seen needles vibrate in, and idle screw speed vibrate out, and cause this).
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Old 04-01-2009, 09:41 PM   #10
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It works again. Just turned it over for about 40 seconds with my finger plugging the exaust and all of a sudden fuel started to go into the carborator. Thanks for all the help
Sometimes if the engine is very dry inside it will take a while to suck up the fuel.
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Old 04-01-2009, 09:42 PM   #11
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40 seconds??

you've got a leak somewhere in your fuel system, should only take like 2 seconds
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Old 04-01-2009, 09:43 PM   #12
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40 seconds??

you've got a leak somewhere in your fuel system, should only take like 2 seconds
+1 could be an air leak anywhere in the system.
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Old 04-01-2009, 09:45 PM   #13
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cap the pipe with your thumb while tapping it on the starter box... it has to push fuel at that point, unless the starter box is turning the motor backwards.

Also alot of the big starter boxes like the blue ofna one turn the motor way too fast IMO. The motor doesnt have a chance to get a good down stroke to create vacumn inside the carb venturi to draw fuel. They practically burn up the piston and sleeve without even running the engine because there's no fuel in there to lube it. I've felt engine that guys havent been able to get started on those boxes and the engine is hot.... and it hasnt even ran yet..
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Old 04-01-2009, 10:16 PM   #14
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Take both lines off and plug the carb line with your finger. Blow in the exhaust line if you can't blow at all then your good with no leaks.

If you can pass air then listen to see if its coming from the tank since you checked the lines already to make sure you don't have a leak on the O-Ring in the fuel cap, or have a crack in the tank.

Last edited by RJNicholson; 04-01-2009 at 10:17 PM. Reason: typo
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