I have a Honda GCV160 on a Craftsman mower. It runs smooth and strong at idle and high speed, but it runs rough and misses at all the speeds in between. I cleaned the carburetor, replaced all the intake gaskets and it has a brand new air filter. The spark plug is also new. Any suggestions?
Manual or Automatic choke? Does it appear to be working properly? For autochoke, be sure it is not binding or sticking.
You may want to review the cleaning procedure here and be sure you absolutely cleaned the carb properly:
How to Clean a Honda Carburetor
Even with a carb cleaning, it is very easy to miss something, as it only takes a tiny, tiny bit of debris or slime deep inside the carb to cause poor fuel delivery. Genuine Honda carbs are quite inexpensive (<$25) and can often resolve poor running engine problems. To get a new carb, first get the full serial number off the side of the engine block; it is in the form of GXXXX-1234567. Next, you can go to Honda's official parts look-up site and get the exact part number for a new carb:
Honda Power Equipment, Engines and Marine Factory Parts Lookup
Once you have the part number, Google it to find a Honda Dealer selling it online, or use this link to find a Honda Dealer in your area:
Find A Honda Dealer
Finally, when fitting the carb back, be absolutely sure of the position and orientation of all gaskets, insulator, spacers, etc. It is easy to get one or more on upside down or backwards.
