Help me troubleshoot myb 225 hp mercury
 

Can anyone help me?

I have a mercury 225 offshore series motor. When it is idleing out of the water, with the muffs, It smokes normally. When I put it in the water, when i first start it , it smokes until after i run it awhile, no more smoke. Now it is starting to have noise. Is there a way that i can check the oil or bypass the oil enjection system and mix my oil in the tank to be sure?
Any advice will be appreciated

What year?
Carb. or EFI?
What kind of noise?

I had an Offshore 200 HP carbed. Mercury. She smoked at start up, until she warmed up, then no more smoke. She did that for the whole 14 years I had her.

I would go run the boat with a mechanic; you could cause major damage trying to troubleshoot problem.