It could be that the mower was tilted on its side or that the rings are bad.
You probably have a bad turbo.
You may have oil on the exhaust, once this has burnt off the smoke should stop.
cause so times if you crash in a rock or a tree . then the oil comes out of the pipe
The burning smell from the exhaust pipe may be caused from oil or transmission fluid leaking into the exhaust pipe. For example, if your turbo is failing on the car, then that can cause leakage from the manifold into the exhaust pipe. There may be other reasons, too, which other people will be better articulating.
Maybe a blown head gasket
if it's coming from the tail pipe or an exhaust leak, it means you have a blown head gasket!
No, it will not cause smoke from the exhaust pipe. However the leaking oil can drip on the exhaust manifold where it will be burnt and smoke.
Valve cover gasket is probably leaking oil onto the exhaust manifold or the oil filter may be leaking oil onto the exhaust pipe.
Back of the block, to the left of the exhaust pipe.
On front of the motor, beside the exhaust pipe.
No. The only substance that should go into an exhaust pipe are the combustion gases from the burning of fuel in the cylinders.