I know its not good but

[sir-vivor]

I have a bud who has a sister kicker to mine and was just wondering if maybe I should be watching mine closely Whew ( I changed that oil a few days back so alls good with mine ).
Its a 2015 Yamaha 9.9 HT and he always has the oil changed by a local Yami dealership.
He took his kicker in for its annual oil change and was advised they found water in the oil ..... WTF !
What could every casue that ?

 

[Corey_lax]

Blown head gasket?

 

[salmonkiller01]

I am going to guess thermostat stuck open. I thought my kicker was getting water in oil. Oil was milky after one use. Changed thermostat and all good

 

[Buckethead905]

I am going to guess thermostat stuck open. I thought my kicker was getting water in oil. Oil was milky after one use. Changed thermostat and all good

This

 

[kevind]

I am going to guess thermostat stuck open. I thought my kicker was getting water in oil. Oil was milky after one use. Changed thermostat and all good

that was the cause in my mercury kicker. It would be the first thing I check.