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Walbro carb help

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Old 11-08-2003, 08:48 PM
  #1
zipnsplat
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Default Walbro carb help

Hello all,

I just finished my first gas conversion tonight. This is also my first experience with gas engines as well. I converted a homelite 25cc engine and put a Walbro carb on it. Well, when I fire it up it will die unless I hold my thumb over the velocity stack. This to me says that the engine is not getting enough fuel, but it dies no matter how rich/lean I have it. Any ideas? I removed the butterfly choke from the carb. Do I now need to plug the holes in the carb where the choke was? Also, the carb has 2 nipples. 1 for fuel, and one that feeds back into the tank. how can I make sure that I don't have them reversed? Thanks for the help.

-Zip
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Old 11-08-2003, 10:06 PM
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w8ye
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Default RE: Walbro WT433 help

The needle valves ae closer to the side that goes back to the tank.

Unless you have one of those little thumb pumps in the circuit, You better just plug the return so it will not suck air.

It sounds as though your impulse circuit from your crank case to the pump side of the carb is blocked some way?

http://wem.walbro.com/walbro/product...m=WT%2D433%2D1

Jim
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Old 11-09-2003, 01:53 AM
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mikenlapaz
 
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Default RE: Walbro WT433 help

Or maybe there is a small air leak in the fuel connections coming FROM the tank.

(Unkowingly I bought Large fuel line first time and even with hose clamps the Tygon seems to fit loose, seems like the 3/32" , medium might be better on runs under 12". Any comments.

Restriction/kink in fuel line would starve the engine also.
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Old 11-09-2003, 11:57 AM
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Default RE: Walbro WT433 help

Tygon is not the best fuel line..There is no reason to use anything larger than the small neoprene fuel line on any gasser..I run engines up to 150cc on Hayes products molded neoprene fuel line..No clamps needed, does not get stiff, works well for clunks in the fuel tank...The inside diameter is about 3/32..
I get it from Custom Injection in Garden Grove, Cal...714 554 0531...
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