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Excessive fuel coming out of the tuned pipe

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R

rcradical

RC Newbie
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I've got a Traxxas T-maxx 2.5 that has nitro fuel runnin out of the tuned pipe. It started shortly after what i call a backfire and its unburnt fuel spraying out the pipe. Any ideas as to what is wrong and how to fix it?
 
Usually sprays bad when its way too rich. Try leaning the hsn a little at a time till your performance is good. Also usually what comes out of the pipe with a good tune is oil not fuel.
 
You say it was after starting. Its normal to spray some fuel after chocking the engine to start it.

Its also going to spray the unburnt oil from the fuel as it runs.
 
This is actual fuel coming out of the pipe. I have tried setting it back to factory setting and it still spews out even as its running. It was runnin fine up til it backfired.
 
Time to break the engine down and visually inspect the sleeve piston and rod. Also check the crank bearings.
 
Is the fuel coming from the header out of the engine or from the fuel line on the pipe?

If you have the lines reversed, fuel can backfeed from the tank into the pipe. The line on the bottom of the tank should go to the carb and the one from the pipe to the top of the tank.

I guess it can make enough fuel pressure to flow the fuel up and run barely. Then when you let off the throttle and the pressure in the line drops the fuel backflows into the pipe.
 

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