I have a 1978 Honda Express. I can get it running and give it gas and it dies out. I don't have a an air filter box. If I cover that hole then it runs and I can even hit the throttle. I never had this problem before what kind of adjustments can be made? I figure there must be an adjustment on the carburator for air intake. Any Info...Hurry I have to be to work by 5:30pm.