Small Engines (Lawn Mowers, etc.): Lawnmower Carberation Problem, piece of dirt, free float

Question
I have a Sears 6.6 hp rear-propelled bagging EZ^3 mower, model 917.377340, with engine model 143.976606.
It recently began quitting when the mower is aimed even slightly down hill or on a slope toward the carb side.
I have to bump the primer to restart and it will run forever if i leave it flat.  Soon as i head down hill at all, it stalls.
I thought it might be dirt in the carb, so i took it apart and cleaned it with carb cleaner, but the same symptoms remain.
Weird huh?  Have you seen this before? Any Ideas?

Much appreciation in advance,
Christopher.

Answer
Hi Christopher,

I would check the carb float.  It may be sticking, out of level or fuel logged.  Remove the bowl and check for free float movement.  The float should be level to the carb body.  Then feel if the float is heavy.  If it is hollow brass, you may need to remove the float and shake it to know.  If sticking, you will need to replace the needle and seat.  Or the problem might be a piece of dirt inside.

Let me know what you find.
Michael