"My 12HP 2GM has about 1200 ho
"My 12HP 2GM has about 1200 hours up, and revs nicely to about 1800rpm. But any more throttle beyond that just leads to black smoke and no increase in revs. I think it should rev out to somewhere around 3000 (the manual says max is 3400). I've only just bought the boat so can't say if this is a recent change or not.
I've tried running it with the air filter off to eliminate intake restrictions, but no luck. I've been told by the guy who serviced it for the previous owner that he's pretty sure it's not over-propped, and he said the exhaust water trap could be coked up. I've heard of mixing elbows coking up (I'll be checking that this weekend) but not traps. Has anyone come across a coked-up trap?"
"My 12HP 2GM has about 1200 hours up, and revs nicely to about 1800rpm. But any more throttle beyond that just leads to black smoke and no increase in revs. I think it should rev out to somewhere around 3000 (the manual says max is 3400). I've only just bought the boat so can't say if this is a recent change or not.
I've tried running it with the air filter off to eliminate intake restrictions, but no luck. I've been told by the guy who serviced it for the previous owner that he's pretty sure it's not over-propped, and he said the exhaust water trap could be coked up. I've heard of mixing elbows coking up (I'll be checking that this weekend) but not traps. Has anyone come across a coked-up trap?"