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NS3.5A leaking fuel intermittently

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whitegreg56

Regular Contributor
It's an old 2-stroke that sometimes drips fuel like crazy from the front
of the engine when it is tilted up. The serial # is 309-190829.
I guess this is a stuck inlet needle inside the carburetor. Shall I
replace the whole thing for ~$120 or get a kit and take a crack at
rebuliding it myself?
 
Of course the fuel cock should be turned off when tilting. If the needle/seat is weeping, install a carburetor repair kit. Kit includes gaskets, float & needle valve, Part # 3F0871221M, $44.11, available from any dealer, including me.
 
It never leaked when tilted up, until recently. If the tank is full, the vent screw definitely needs to be closed.

I decided to install a whole new carburetor.....it went right in.....engine runs fine.

Time will tell, if it still leaks.
 
Guess what?....It still leaks.
Thought it might be due to particles from the decay of the old fuel line (ethanol?).
So, I disassembled the old carb....the float bowl is as clean as a whistle.

At this point, the only thing I can think of is the junction between the fuel
line and the inlet barb on the carburetor....although the hose seems tight,
the clamp spring is not.

Any other ideas????
 
Paul - It's an old, frequently-used engine that never leaked when tilted
up, until recently. We've always left the fuel cock on until the
sail is over and then run it dry. I'm going to take it apart (again)
and take a closer look.
 
Since the fuel is under gravity pressure even when not tilted, if the fuel line connection at the carb inlet were dripping, it would do it even when running... so that's not a likely problem. You do want to close the fuel cock when tilting -- that's on p20 of the owner's manual. Depending on the gas level in the tank, tilting could raise the fuel cock and in-tank strainer above the gas, but if the tank is nearly full, you will have the carb at a radical angle, and fuel pressure to it... no way for the float to fully close the needle to stop dripping.
 
OK, Paul....you win....We'll close the fuel cock everytime we tilt it up.
Incidently, the new carburetor seems slightly different in terms of
how far the throttle lever needs to be up in order to start the engine.
We have to get used to that. It'll get a good shakedown, tomorrow.
 
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