Hi folks,
This forum looked like a good place for advice and help, so here I am.
Bought a used Yamaha 4 hp four stroke at the end of the season last year and had a problem when I tried it out on my inflatable. Was hoping someone coud deliver the bad news to me before I took it into a shop.
Bear with me, as the motor is in storage, and I'm going from memory here. I believe it's a 2003 (maybe 2004), short shaft.
It starts up fine...one or two pulls...and seems to idle fine. However, after putting it into the water on a lake for about 10 minutes, when I turned if off, white smoke was coming from under the engine cover. I took the cover off and there was smoke there...not a huge amount but definitely there before the wind blew it away. I thought a wire or something was burning, but there wasn't much of an odor. I'm 99% sure it wasn't steam...it looked like cigarette smoke from about four smoldering cigarettes.
As this was/is my first four stroke, I have no idea what might cause this. I wasn't quite sure how to test if it was overheating, or what to look for.
I let it sit for a few minutes, started it up and went back to the dock. One thing I did notice was the power/torque all came from about the first half or two thirds of the throttle. The remaining throttle didn't increase speed or even change the sound of the motor. As it's only a 4 hp, I figured that might be normal when trying to push even an inflatable boat. Anyway, sure enough, when I glided up to the dock and killled the motor, the smoke was back.
I know this is vague, and I probably shouldn't have restarted it to get home, but I did. And I do know that white smoke is usually not good. So if you have any idea of what could cause this, or what I might have to do to fix it, I'd sure appreciate the help.
This forum looked like a good place for advice and help, so here I am.
Bought a used Yamaha 4 hp four stroke at the end of the season last year and had a problem when I tried it out on my inflatable. Was hoping someone coud deliver the bad news to me before I took it into a shop.
Bear with me, as the motor is in storage, and I'm going from memory here. I believe it's a 2003 (maybe 2004), short shaft.
It starts up fine...one or two pulls...and seems to idle fine. However, after putting it into the water on a lake for about 10 minutes, when I turned if off, white smoke was coming from under the engine cover. I took the cover off and there was smoke there...not a huge amount but definitely there before the wind blew it away. I thought a wire or something was burning, but there wasn't much of an odor. I'm 99% sure it wasn't steam...it looked like cigarette smoke from about four smoldering cigarettes.
As this was/is my first four stroke, I have no idea what might cause this. I wasn't quite sure how to test if it was overheating, or what to look for.
I let it sit for a few minutes, started it up and went back to the dock. One thing I did notice was the power/torque all came from about the first half or two thirds of the throttle. The remaining throttle didn't increase speed or even change the sound of the motor. As it's only a 4 hp, I figured that might be normal when trying to push even an inflatable boat. Anyway, sure enough, when I glided up to the dock and killled the motor, the smoke was back.
I know this is vague, and I probably shouldn't have restarted it to get home, but I did. And I do know that white smoke is usually not good. So if you have any idea of what could cause this, or what I might have to do to fix it, I'd sure appreciate the help.