Small Engines (Lawn Mowers, etc.): briggs 5hp will start and idle but not rev up, valve job, govenor

Question
I have a 5hp briggs that I trying to to fix .
when I recived it,it would not start,I took the head off and found the valves were sticking,
I loosened them.put the moter together, but now it will start and idle,but dies when I try to rev it with the govenor. the trottle slide does nothing, I was wondering if the valves need a light cleaning with emory cloth ,or fine grinding compound.this is an upright moter off a tiller
thank you Raye  

Answer
How old is the engine?  A good valve job wouldn't hurt anything.

If the engine is old, and off a tiller, then there are numerous problems that can cause this problem.  The reason for this is wear;  tillers are ran in the worst contidions and those engines typically wear out quickly.  Dust enters the carb, governor shaft and many other places.

I've some of these engines where I could never get them to run correctly unless I rebuilt the engine and replaced the carburetor.

In you case, have you tried adjusting the carb or cleaned the  carb?
Let me know.
Eric