Small Engines (Lawn Mowers, etc.): Cub Cadet 2165 stalls - low horsepower, cub cadet 2165, governers

Question
Cub Cadet HDS 2165
Cub Cadet 16HP v twin
Serial 314141

Engine runs strong for 30-45 minutes then begins to cycle up and down. Has
low horsepower and occasionally stalls out entirely. Applying 1/4 choke helps
slightly for a while. After a long rest (between mowings) it works fine again.
Also, will occasionally run poorly for a while, then run well, then poorly, then
well..etc.

any help? I'm assuming a carb-rebuild is in order.. but I've heard talk about
"governers".. don't even know what they are...  

Answer
Doug
Sounds like the"coil breakdown" check for spark when it dies.Or carb problems starving for fuel.Check the fuel system completely starting with the tank make sure it is clean the fuel lines the filter the fuel pump and remove the carb bowl to see if there is dirt in there.

Thanks