2003 sx150 exhaust fumes

[vpcei]

If anyone has had this kind of problem and could shed some light on this it would be greatly appreciated
have a 2003 ox 66 salt water 2 stroke 150 hp that gives off real bad exhaust fumes to a point that you cant sit in the back of the boat
also seems to be slugish under load
o2 sensor seems to carbon up quickly and plugs seem to show fouling tendancy
adjusted oil pump stop, new plugs,new filters, changed low pressure pumps about 2 years ago
thank you
vinny

[boats.net]

Use 87 octane gas(fresh gas) and Yamalube oil, add Yamaha RingFree to gas. Have the throttle linkage and TPS checked and synchronized. Have thermostats checked to make sure engine is not running too cold.

[vpcei]

more info

only use yamalube, boat is used often fuel every weekend from local gas station 87 oct, ring free at shock rate from aux tank, new thermos last year and still had this problem will try tps when boat gets uncovered, thanks for your input
vinny