my mower is smoking bad

my john deere L130 runs but is smoking badly, seems to be worse when there is a load on engine .i checked the plugs but they didn't seem to be oil fouled
the engine is the Kohler command 23 any ideas on a cheep fix would be appreciated

Nothing usually cheap on a smoking motor. Unless you overfilled with oil or carb is leaking fuel into crankcase. Next cheapest fix is probably a blown head gasket. Other than that it’s usually mechanical wear .