When i cut on heat run about 45 cut off smoke blue?

- Make sure the blades are sharp
- Make sure the drive belts are in good condition and under tension when in cutting position
- Make sure that straight gas is in the fuel tank (NOT MIXED)

Other problem could be bad piston rings. PITA to fix. If it runs good and cuts ok after the above checks, I'd run it and live with a bit of smoke.

Blue smoke would indicate its burning oil. Oil is bypassing the piston rings or valves and is entering the combustion chamber where it is then burnt off.
Small engines are easily rebuilt, usually less than $100, most people just run it until it drops or buy a new mower.

i believe the engine is running too lean as if it was running too rich it would blow black smoke If it was blue smoke it is oil related eg valve stem seals,valve guides and or piston rings all of these things will create blue smoke if one of the above is worn out

What are you asking ?

Sounds like the motor is gone mechanically

blue smoke indicates oil is burning in the cylinders. This is either leaky valve seals, (little blue smoke when engine first starts, but stops smoking shortly after) or the worse problem, worn rings. What happens is when your rings are worn, they let oil get past the rings and into the combustion chamber, AND it also lets out your combustion pressure (your power source) into the crankcase, so you have considerable power loss. Only way to fix worn rings is to rebuild the engine, as just replacing the rings would require complete teardown of engine anyways, and who wants new rings in a worn out motor.

White or blue smoke? If white does your hand get damp holding up to the tailpipe when the engine is running? Does the radiator boil over/engine over-heat easily? Flat head engines are notorious for running hot especially if not moving. Flat-heads don't cool well as a general rule and the older radiators are not very efficient heat exchangers. If the smoke is white then the headgasket is blown or the head or block is cracked (the first two are more common). If the smoke is blue then the valve guides and/or the piston rings are worn fairly severely. Ironically the easiest way to damage the piston rings or valve guides in a flat-head is to run it hot.

Check your air breather filter.

i would suggest checking into the throttle positions sensor. the smoke makes it sound like the car is flooding.

probably the oil rings on the pistons but might be one of the heads , not good either way