Carburetor help needed.

My qt50 has not been running for a couple of months. I recently found some time to try and fix it and upon inspection found that my pilot air intake adjustment screw was completly missing. I'm wondering what kind of direct effect this would have on the operation of the moped. I'm assuming it would not start at all which is my current problem. However, the moped was starting rough for the 3 months I rode it in the spring and I had never properly prepped it for winter storage and had assumed the problem was a gunked up carb. Eventually it just completly wouldnt start at all. Today I took the carb apart and it is very clean so I don't think that was the problem. Anyways I'm wondering if anyone has ever run into something like this before. Thanks in advance for any help.

Re: Carburetor help needed.

not much to say .. except get another mixture needle. seems that a missing pilot air screw would allow a constant stream of excess air to get sucked into the carb through the vacant hole, upseting the mixture, just like a vacuum leak wouild.

Whether or not the needle affects fuel delivery beyond start/idle depends on the carb's design. I know on the carb on my bike, starting, idle and low-speed fuel/air supply quantity depend somewhat on the idle air-mix needle adjustment.

Spray some Starter Fluid into the carb intake or into the spark plug hole.. if it starts, ignition is ok but the carb is not delivering fuel. It could be due to the missing screw or to something else.

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