Small Engines (Lawn Mowers, etc.): Kawasaki 17 hp valve problem, toro mower, valve guide

Question
Mr.Jones, I have a Toro mower with a kawasaki 17 hp V-twin engine, model# FH500V.  I have an intake valve that is very hard to push and out. I removed the head and the valve to examine it but did not find anything wrong with it except that it was covered in carbon.  I cleaned it, and re-installed the head, and added Seafoam to the gas. The valve was very easy to push in and out at this point in time.  I now have put 2 hours on it and the same thing is happening. I cant push it in with my thumb at all. Do I need to replace the valve guide or use some other lubrication on the guide?
Thanks in advance.

Answer
The valve shouldn't be too easy to move in and out.  If it's sticking in its travel then you may need a new valve and guide.  The valve should be lubricated by the engine oil.  I really couldn't diagnose if there's a valve problem without seeing it.  But if you think there's a problem, pull the valve and see if it's straight.  Thanks, PK.