Accelerator Pump Outlet Check Valve Missing

I was rebuilding my carb and the outlet check valve between the accelerator pump and the nozzle mysteriously disappeared. Anybody know what would happen if I tried running without it?

You may not notice anything wrong but it potentially can cause nozzle to drip.
i see youre asking about a transmission, you have to readjust the throttle valve cable when you use a weber. That can cause a lot of different issues, one being the bucking, bad shift points, no shift etc.
The setting is sensative to any change in tune, throttle position , timing and throttle idle stop setting.