Got the Tech HH160 running this afternoon, but it wants to surge a lot at all speeds. With the air cleaner off I can see gas bubbling up from the tube in the middle of the carb. I know this is not normal but wondering where to look for the problem. Fuel tank was clean, new fuel line and filter. Carb was cleaned and blew out good. Float was set so it was level when right side up. My thoughts are dirt in the high speed fixed jet. No change in the slow speed jet helps any. Appreciate any advise you might have.