As you have a 4/str,this is what I used to do before I retired.
1/ put a stabalizer in the petrol and run it so that it is all through the fuel system.
2/ when you are happy that the stabalizer is all throgh the system/
3/ remove the spark plugs, with each piston at B.D.C. sqirt a small amount of new clean engine oil into the top of the cylinder ,so that it runs down the side, do that to each cylinder, making sure that the kill switch is in the kill/not able to start position.
4/ with the sparkplugs re-fitted turn the engine over BY HAND ONLY, to make sure that it doesnt hydraulic lock.
5/ change the engine oil and filter
6/ sell the fogging oil to someone with a 2/str