2005 mercury 90hp 2 stroke. Cough

[Brianvandjr87]

The motor coughs or misses and then most times dies. There is a puff of smoke that comes out of the bottom cowl when it does this. I have some experience with outboards and I believe this could be a failed base gasket. All advice is appreciated, I want to be sure before I start tearing in to it. Thanks!

 

[mechanicman]

If you see smoke in the cowl. The base gasket may be compromised. Yes.
The coughing and missing may be due to carbs dirty or mixtures out of adjustment.