The smoke unit stopped working. been run only 5 minutes

Is running electric or fuel? The first thing you should check is if the unit is clean, free of dust and deposits.

Mate I use to drive a freightliner and it cut out on me one day, I eventually got it started but cut out again after about 5 minutes, I rang a mechanic to come out and he found a heat sensor wire came off the radiator and that caused the motor to cut out... Hope I haven't wasted your time.......

I think... without knowing that motor... that the capacitor is a start capacitor, and that the start switch may be trying to "start" the motor full-time instead of switching it out of circuit after it figures that the motor has spun up. I may be wrong - that design may be a capacitor-run motor (similar to a three-phase motor) - but I'm betting it's a start-only capacitor.

If you know someone with a capacitance meter, you could check the capacitor - for both capacitance (to be sure it matches the label) and leakage. Easy way to write that one off. Alternatively, you could rig it such that after the motor's wound up you could manually disconnect the capacitor and see what happens - either the motor stops or else the smoking issue stops.

Whatever you do, don't let it smoke very long. The varnish on the windings is only so thick.

These are great little engines and do not suffer with too many things, first to look at clogged spark arrester in the muffler out let, remove and lean, check the fuel hoses have not become brittle and have cracked and are leaking, failing that check the ht leed where it runs close to the cylinder, is it arcing out? i have replaced a few ignition units, so you can never rule this out.

First check the oil level. If its overfilled correct it. Then remove the spark plug and turn the engine over. Replace the spark plug.
Start the engine. Use a prime ( squirt carb cleaner into carb) if you need to. It may start smoking again. Thats OK as long as you know there is oil in it and you dont hear any strange noises. Let the unit run for about 5-10 minutes and see if the smoke clears up. Once it quits smoking stop it and check the oil.

time to replace valve guides

If you need further help, I’m available over the phone at https://www.6ya.com/expert/michael_00678fd4800d19c5

Due to abnormal temp of out door.Check outdoor fan motor and compressor and also sensor.
Fan motor not working- rectify/replace fan capacitor.
Sensor defective-Replace it
Compressor high amps-Replace running capacitor.
Sensor misplaced or defective-Place correctly or replace it.

Oil level too high? *(check oil level with dipstick fully screwed down!)

or

Leaking valve guide *(rare.)

Cylinder walls not sealing well and oil leaking past rings. *(less rare...nothing you really can do about....just getting used up)

I would change the oil and be very careful to fill only within the full range.
Then, run the unit once to clear the muffler out.

Good luck and be careful!

If the black smoke comes out of the muffler, you are burning excess fuel and could have an air filter plugged up to restrict air intake and cause the engine to run rich, therefor black smoke.

My first thought is that the throttle lever is being pushed so far forward ( max RPM's ) that you are running the engine 1/2 or better choked
Look at the choke butterfly with the throttle in your normal run position it should be completely open
This may require and adjustment in the control rods or might be as simple as not pushing the throttle wide open