I have a 1996 Evinrude 115 horsepower two stroke that will not start apparently due to a sneeze problem. It will turn over and Fire, but will not idle. Maybe one in 10 attempts, it will run for several seconds before letting out a big sneeze and then the motor dies.
From what I understand, this indicates the possibility of a lean sneeze, caused by air being introduced prior to combustion.
Here's some background. I bought the motor about 7 years ago after it had been sitting for several years. I had my mechanic rebuild the carburetors, and the motor ran flawlessly for a couple years. Then, it started to have difficulty starting -- it would fire and then run for a few seconds, and then die, and then fire and run for several seconds, Etc , and this would go on for a while,...,it would take 10 minutes to start it to where it was running good, but once I got it running and worked through whatever problem it was having, it would run completely normal for the rest of the day... I could turn it off and then start it right back up with no issues... for the rest of that day, and even into the next day, it would start and run perfectly. But if I waited a few days or more, I would have difficulty starting it again. I know, sounds strange! But that is what it was doing. For a few years actually.
The problem got worse and worse the past year, and I just recently had a mechanic diagnose a faulty electric choke (primer) and so we replaced that item, which I had hoped would solve the problem. It improved the situation, but the starting problem was still there, and its gotten worse the past couple months to the point that it will not start and run for more than a few seconds before dying with a sneeze. I don't believe this sneezing was present at least to this degree prior to this year, but the difficulty in starting it has been there like I said for several years. When I turn the key now and start it, it will fire and then sneeze and die. Sometimes I can get it to run for several seconds, but eventually it will let out a big sneeze and die.
I have not done much since the rebuilt carburetors seven years ago, which as I said, were successful and I had two great years with the motor after the carbs were rebuilt. I 've recently replaced the fuel line/primer bulb and the fitting at my gas tank, as well as the fuel filter. So I am confident that I am getting fuel flowing from my tank to the carburetor. And I replaced the electric choke, as I said. Apparently, it sounds like an fuel system leak. (Air being let in) is occurring somewhere else. Valve Reeds? Bad gasket somewhere? Or perhaps an internal carburetor problem? I don't know. These are just ideas I have gathered from reading the forums. My question is, where should I start and what is the likely culprit?
My boat is currently in the water, and I was hoping to leave it in for another couple months, and it is not very easy for me to take it out to work on it. So I would like to start with the easy stuff first, if there is such a thing.
Any suggestions on diagnosing this starting problem associated with an apparent lean sneeze that has progressively gotten worse over the last few years?
Thanks in advance, Tom
From what I understand, this indicates the possibility of a lean sneeze, caused by air being introduced prior to combustion.
Here's some background. I bought the motor about 7 years ago after it had been sitting for several years. I had my mechanic rebuild the carburetors, and the motor ran flawlessly for a couple years. Then, it started to have difficulty starting -- it would fire and then run for a few seconds, and then die, and then fire and run for several seconds, Etc , and this would go on for a while,...,it would take 10 minutes to start it to where it was running good, but once I got it running and worked through whatever problem it was having, it would run completely normal for the rest of the day... I could turn it off and then start it right back up with no issues... for the rest of that day, and even into the next day, it would start and run perfectly. But if I waited a few days or more, I would have difficulty starting it again. I know, sounds strange! But that is what it was doing. For a few years actually.
The problem got worse and worse the past year, and I just recently had a mechanic diagnose a faulty electric choke (primer) and so we replaced that item, which I had hoped would solve the problem. It improved the situation, but the starting problem was still there, and its gotten worse the past couple months to the point that it will not start and run for more than a few seconds before dying with a sneeze. I don't believe this sneezing was present at least to this degree prior to this year, but the difficulty in starting it has been there like I said for several years. When I turn the key now and start it, it will fire and then sneeze and die. Sometimes I can get it to run for several seconds, but eventually it will let out a big sneeze and die.
I have not done much since the rebuilt carburetors seven years ago, which as I said, were successful and I had two great years with the motor after the carbs were rebuilt. I 've recently replaced the fuel line/primer bulb and the fitting at my gas tank, as well as the fuel filter. So I am confident that I am getting fuel flowing from my tank to the carburetor. And I replaced the electric choke, as I said. Apparently, it sounds like an fuel system leak. (Air being let in) is occurring somewhere else. Valve Reeds? Bad gasket somewhere? Or perhaps an internal carburetor problem? I don't know. These are just ideas I have gathered from reading the forums. My question is, where should I start and what is the likely culprit?
My boat is currently in the water, and I was hoping to leave it in for another couple months, and it is not very easy for me to take it out to work on it. So I would like to start with the easy stuff first, if there is such a thing.
Any suggestions on diagnosing this starting problem associated with an apparent lean sneeze that has progressively gotten worse over the last few years?
Thanks in advance, Tom
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