There should not be a lot of smoke from the slight extra amount of oil in the tank. If there is. You are not measuring the amount of oil correctly. Or you are not mixing the oil and gasoline correctly / well enough.
I know of 4 things to attack metal parts in water.
Salt Water
Polluted industrial / corrosive places
Excessively strong Chlorine sewage treatment plant discharges/
Strong stray electrical currents. Dock power or underwater power cables leaking electrical current into the water.
Success !!
Cleaned out gas tanks and 5 gallon of new 0 % ethanol marine Hi Test. new Primer Bulb. Back to instant starts ....With 2 new gapped correctly plugs. :)(y)(y)
Sounds like the water is taking way to long to warm up. Thermostat is wrong one ? installed wrong ? Choke is wrong ? Missing a gasket under the thermostat ? Temperature gauge is in correct ? A little bit of some problems ?
The key to forever life trailer lights. Is the separate Ground Wire And completely sealed light housings. My oldest trailer is a 1984. I back in with no cooling off of bearings or lights. Day or night lights on.
Electronic PCB and parts ???????????????????? For a simple light to be lit ????????????????? No one can fix
ALL light fixtures MUST be SEALED against any water getting in.
The drain hole ?? :):):):):):):):)
Edit All my trailers still have sealed 12 volt light bulb and socket. No corrosion. Ever