[kbe119]

I don't know much about boat motors so I'm looking for direction. My boat has a Mariner 25 that ran great when I bought the boat 8 months ago. When its at an idle now it is running rough like it is missing a bit, smoking quite a bit and will die once in a while. When I got it it purred like a kitten at an idle and very little smoke. When I run it on a plane it doesn't smoke nearly as much , but I can feel a consistant miss about every second or second and a half. I'm wondering if this could be a fuel mixture problem or if it just needs tuned up and new plugs. Thanks

[lckstckn2smknbrls]

Add some seafoam to your fuel mix.

[JUSTINTIME]

carb is plugged