16 HP Vanguard, surge
 

I've got my engine up and running, and it runs great when i'm working her. however when just moving around the yard I have a surge. is there a common issue with these engines? if not i'll have to start searching a little harder.

They tend to be jetted lean on the slow speed jet. You'll probably need to remove the plastic cap at the back of the carb that prevents you from adjusting it.

I've noticed they have better torque when you leave the choke on a little bit. I've done some drilling in a couple areas of those carbs to get more fuel

It could be a vacuum leak between the carb and engine. I had a B&S 16.5hp IC that did the exact same thing you described. I put a thin layer of RTV on both ends of the plastic intake tube between the carb and engine and the surge went away.

I appreciate the comments. I hope to check it out today

spray carb cleaner or ether around the intake to see if you have a leak . you'll hear a engine rpm change if you have one