HS50 new carb issue no start

I bought a new carb off ebay for my HS50 build. It doesn't seem to be getting gas to the spark plug as the plug is bone dry when I pull it. The plug has spark and will pop the engine over if I give it a shot of starter fluid. I began with backing out the carb adjustment screws one full turn from closed. There is gas in the carb bowl. I'm not sure what to try next. Any help will be greatly appreciated. Thanks!


Active Member
Do you have any pictures? Some carbs have the fuel jet adjustment screw under the carb and the idle mixture screw on the side of the carb. You may want to double check a nice fit with the gasket between the carb and intake and insure no leaks otherwise it won't work.


Active Member
The black screw in your pic is the idle mixture screw and should be about 1 to 1 and 1/2 turns out (1/8 turn at a time once its running to get the best idle and throttle response). In the 2nd post the main jet screw under the carb, it should be 1 and 1/2 turns out as well.

It may be the picture, but I do not see gasket clearly on both sides of the carb to intake. It may be just me, but you may want to look at your gasket is making good contact to the carb and intake.
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Got it fired up, purrs like a kitten. I put my hand over the carb while pull starting to prime it. There must have been an air bubble in there somewhere!