M151A2 engine surges

[catamountinsp]

Need some help; My 151 engine surges and doesn't hold an ideal and I can't figure out why. I rebuilt the card with the soft rebuild kit and the engine has fresh gas. I have seen clips on YouTube reflecting the exact issue my engine has (but there were no comments). https://youtube.com/shorts/WIAl_BsvUX0?feature=share Thank you in advance for any assitance.

 

[NDT]

Pull out the choke half way. Or better yet, send the carb to Brooks Engine Service

 

[lpcoating]

Do you have a vacuum leak? Carefully spray carb cleaner around the intake and see what happens. Was it doing this before the carb rebuild? Float set properly?

 

[INFChief]

The Venturi can come loose. Stick your finger up in to the top of the carb. You might be able to ‘wiggle’ the Venturi with your finger. If you do this with the engine running it might smooth out. There’s a small plastic plug on the top of the carb. Under that is a set screw that holds the Venturi tight. You might need to snug that up.