Have a 8hp 4-str Honda engine...we'll be going along for 15 minutes, and out of the blue, it'll slow down & smoke for maybe 3 seconds, then go away for the rest of the day...???
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Gregory Stebbins
Or maybe...
Whatever it's smoking has got to be pretty good stuff! (I here, I wouldn't know personally. NEVER inhaled!!)
Whatever it's smoking has got to be pretty good stuff! (I here, I wouldn't know personally. NEVER inhaled!!)
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MikeY
No no no no I don't smoke it no more.
Of course it has gas, that's why it runs ! U guys don't have a clue do you :+) It's possible that the crankcase pressure is building up, then when it gets high enough, the rings can't keep the oil from getting up top, then we burn the oil, then pressure builds up again, repeat cycle...
Of course it has gas, that's why it runs ! U guys don't have a clue do you :+) It's possible that the crankcase pressure is building up, then when it gets high enough, the rings can't keep the oil from getting up top, then we burn the oil, then pressure builds up again, repeat cycle...
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Greg Stebbins
Ditto.....
But I liked your answer..As far as I concerned, it sounds like it's time to take the Honda to your local authorized bandit. Greg
But I liked your answer..As far as I concerned, it sounds like it's time to take the Honda to your local authorized bandit. Greg
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Alan Long
Smoking the good stuff
Hi Mike 99.999% of the time when you get bluish smoke, there is oil entering the combustion chamber (by design in a 2 stroke, not so good in a 4 stroke). Most likely culprit is worn piston rings and second most likely is valve guide seals. If the motor runs fine otherwise, I'd have it bored, put in new pistons and rings, miscellaneous bearings and seals. It won't be cheap, but the motor should provide many more years of service and you will have avoided the throw it away and get a new one mentality. I just rebuilt my 15 year old 4hp Evinrude and its ready to go another 15...I hope. Good luck Alan Long S/V Random Access
Hi Mike 99.999% of the time when you get bluish smoke, there is oil entering the combustion chamber (by design in a 2 stroke, not so good in a 4 stroke). Most likely culprit is worn piston rings and second most likely is valve guide seals. If the motor runs fine otherwise, I'd have it bored, put in new pistons and rings, miscellaneous bearings and seals. It won't be cheap, but the motor should provide many more years of service and you will have avoided the throw it away and get a new one mentality. I just rebuilt my 15 year old 4hp Evinrude and its ready to go another 15...I hope. Good luck Alan Long S/V Random Access
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Bob Schmit
Troy built
OK,so it may not be related but this used to happen to my tiller when I overfilled the crancase(it's a 4cycle,so maybe related) and some of the oil would get into the crankcase breather which had a hose hooked up to the carb to reburn the vapors(I guess that's what it was for) The oil would get sucked in with the gas and slow down and give a big cloud that would knock back the bigger mosquitos for a good 10 minutes or so. Could this possibly be your problem?- I doubt it, but checking the oil level is cheaper than an overhaul. And I doubt if the mechanic you take it to will make much money on an oil change, with more money to be made in major surgery.
OK,so it may not be related but this used to happen to my tiller when I overfilled the crancase(it's a 4cycle,so maybe related) and some of the oil would get into the crankcase breather which had a hose hooked up to the carb to reburn the vapors(I guess that's what it was for) The oil would get sucked in with the gas and slow down and give a big cloud that would knock back the bigger mosquitos for a good 10 minutes or so. Could this possibly be your problem?- I doubt it, but checking the oil level is cheaper than an overhaul. And I doubt if the mechanic you take it to will make much money on an oil change, with more money to be made in major surgery.
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MikeY
Oil level high ?
I think you're right, the oil may be high. It's hard to tell with that dipstick WHERE it is, but I may change it soon anyways. This should be interesting with it IN the water :+)
I think you're right, the oil may be high. It's hard to tell with that dipstick WHERE it is, but I may change it soon anyways. This should be interesting with it IN the water :+)
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Rick Webb
Not sure, maybe?
Don't know if this applies to outboards but if the air filter is dirty or clogged it may be bringing air in through a breather tube and thus ingesting oil into the combustion chamber. We had a piece of equipment that mud dobbers had built a nest on the air filter housing and it acted in a similar manner.
Don't know if this applies to outboards but if the air filter is dirty or clogged it may be bringing air in through a breather tube and thus ingesting oil into the combustion chamber. We had a piece of equipment that mud dobbers had built a nest on the air filter housing and it acted in a similar manner.
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Alan Long
One sure way
One sure way to find out is run a compression test. If it is low, its pistons and or valve leakage. Way to narrow that down is to put a little oil in the cylinder and run the test again. If the compression comes up, its rings..if not its valves. Best news would be if compression on both cylinders is ok. That means the oil is making its way in there via the air intake somehow. (overfilled probably) Most important question is how many hours are on the motor...a lot? Probably low compression...not many?....probably overfilled. Good Luck
One sure way to find out is run a compression test. If it is low, its pistons and or valve leakage. Way to narrow that down is to put a little oil in the cylinder and run the test again. If the compression comes up, its rings..if not its valves. Best news would be if compression on both cylinders is ok. That means the oil is making its way in there via the air intake somehow. (overfilled probably) Most important question is how many hours are on the motor...a lot? Probably low compression...not many?....probably overfilled. Good Luck
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MikeY
No air filter
Don't think it's clogged air filter as that smoke would be black, overrich... I think it's overfilled, and will change it this weekend, in the water, not the oil that is, but the boat. looks like I can lossen the screw, tilt the engine, and then remove screw, drain oil. Oh yes, it has a LOT of compression for a 200cc. It also starts the first-sec try in 40degree weather. We broke thru the ice a month ago to go sailing :+)
Don't think it's clogged air filter as that smoke would be black, overrich... I think it's overfilled, and will change it this weekend, in the water, not the oil that is, but the boat. looks like I can lossen the screw, tilt the engine, and then remove screw, drain oil. Oh yes, it has a LOT of compression for a 200cc. It also starts the first-sec try in 40degree weather. We broke thru the ice a month ago to go sailing :+)
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