oil shim on water omc cobra 4.3 Ltr

[hatsikidee]

Hi there, own a four winns 4,3 ltr (1990) changed the plugs, gas filter oilfilter plus oil but when boat is on temperature a light shim of oil apears on water coming from exhaust. Is my engine running to rich and the gas is not burned completely?
Oil level engine is still ok, last time I even saw som white/lightbraun spots that gave an oily shim on the water. Please help

 

[Bondo]

Ayuh,..... Welcome Aboard,...... What did the old spark plugs look like,..??

The sheen yer seein' can be 'bout any oil from 'bout anywhere, motor or drive,.....

 

[hatsikidee]

Yeah, the plugs I pulled were carbon colored black...I think its time to consult a technician