Hi,
I've got a -97 4-stroke 50 HP mercury (4 cylinders with carburetors). This summer I all of a sudden got a problem with sticky floater valves so one of the carburetors was overflowing and the engine just flooded. As I was on holiday I didn't have the tools for fixing it myself and had it looked at by a local mechanic. He stated that he "cleaned the whole system", and that he'd gotten some solids out of the carb's as well as a little bit of water. I have been meticulous about adding fuel stabilizer, etc before the winters, but still. Anyway the engine was running OK on low rev's although a little bit rough idle. But I could only get around 4700 RPM's max on it. It used to be 6000 max with same prop, which is what it should do. So when I got home I adjusted the idle mixture and balanced the carbs, and now it runs just beautifully on idle. They were really off balance by several cm's Hg so it was clearly part of the problem.
But - I can still only get around 5000 RPM's max "coughs" a bit if I rev it up quickly. I am thinking that since nothing else has changed it is probably still some gunk left in the carbs/fuel system, and I should give it the big overhaul this winter, change hoses, clean out carbs, etc.
However, before I go ahead on this task (I hate fiddling around with carbs), I'd like to ask if anyone in the forum has any similar experience and/or helpful tips as to what the problem might be? I'd be very grateful for any tips you might have.
I've got a -97 4-stroke 50 HP mercury (4 cylinders with carburetors). This summer I all of a sudden got a problem with sticky floater valves so one of the carburetors was overflowing and the engine just flooded. As I was on holiday I didn't have the tools for fixing it myself and had it looked at by a local mechanic. He stated that he "cleaned the whole system", and that he'd gotten some solids out of the carb's as well as a little bit of water. I have been meticulous about adding fuel stabilizer, etc before the winters, but still. Anyway the engine was running OK on low rev's although a little bit rough idle. But I could only get around 4700 RPM's max on it. It used to be 6000 max with same prop, which is what it should do. So when I got home I adjusted the idle mixture and balanced the carbs, and now it runs just beautifully on idle. They were really off balance by several cm's Hg so it was clearly part of the problem.
But - I can still only get around 5000 RPM's max "coughs" a bit if I rev it up quickly. I am thinking that since nothing else has changed it is probably still some gunk left in the carbs/fuel system, and I should give it the big overhaul this winter, change hoses, clean out carbs, etc.
However, before I go ahead on this task (I hate fiddling around with carbs), I'd like to ask if anyone in the forum has any similar experience and/or helpful tips as to what the problem might be? I'd be very grateful for any tips you might have.
