Yesterday I replaced the carb on my Honda HRZ mower. I replaced all of the gaskets, even a new insulator between the carb and the intake. Before it was leaking gas badly but still would idle smooth as glass. Now of course the gas leak is gone with the new carb, but now @ idle, the rpms go up and down like a vacuum leak. I took carb cleaner and sprayed in the area of the carb, and it smoothed out, which to me would mean there is a vacuum leak. Is it possible to install the gaskets wrong,[i.e. upside down or backwards?] Because I tried to make sure by replacing all of the gaskets, I wouldn't have any problems. HELP!