Small Engines (Lawn Mowers, etc.): Craftsman 6.5 hp mower boggs and wont stay running, short grass, water in the fuel

Question
Have a Craftsman 6.5 hp 21 inch mower. model #917.388140  ran great till about 2-3 weeks ago.  Starts bogging when I cut the grass, even short grass and won't stay running with any sort of load.  New plug and air cleaner.  I pulled off the top and there is some sort of electronic servo pulling a cam attached to the carb back and fourth. If I push the  primer the motor will pick up some but then boggs again. I can hold this cam wide open and it will still bog until I give it a squirt from the primer, then it really picks up, but will bog again when put under a light load.
Any thoughts?
Thanks
Jay  

Answer
Hi Jay,

Since you get power when you add fuel with the primer, I suspect that the carb has dirt, debris or gummed fuel inside.  You will need to remove the carb, disassemble it, clean all the small internal openings and blow it out with compressed air.   Probe each and every hole with a small wire.   Adding a carb rebuild kit wouldn't hurt either.  

Another possibility if the problem is fuel related: Check the gas cap to make sure it is venting and not causing a vacuum in the tank.  Also check for water in the fuel.  

Let me know how you make out.
Michael