2006 50hp 2 stroke , blue smoke low idle

[darrfell]

I put some oil in it 3 weeks ago after it started beeping at me. I made sure I used TRw3 oil. It stopped beeping and now I have smoke coming out. I was in a rush to get the boat put away and have yet checked to see if there is spill assuming there isn't. Is there any other suspect cause?

Darrell (green horn outboard owner)

[boats.net]

2 stroke engines will smoke. Some oil brands smoke more than others, the Yamalube or other engine manufactures oils burn cleaner than some oils but it's hard to say if what you are seeing is normal or excessive smoke.

[throrope]

I suspect the beep was from the low level sensor from the on engine oil tank. I make a habit of filling the tank with every fuel purchase and before leaving for a trip. I also keep a quart on board. As long as your oil can listed TRW3, I doubt the idle and the oil have anything in common.

I see you list yourself as a green horn. I was same two years ago. At the risk of being presumptuous, unlike automobiles and other 4 stroke motors, two stroke outboards are lubricated by mixing oil and gas together. Or in other words, the oil is consumed by the engine by design and running out will end your outboard's life.

We had poor idle from day one on our '04 until I found ethanol had eaten the upstream fuel hoses and crapped the carburetors. After three trips through them clearing the crap, passing a bristle from a brass brush through the pilot jets, applying carb cleaner and blowing compressed air through both ends of the passage, we got back on track. Discounted OEM replacement gaskets available here were a big help. Blowing carb cleaner down the intake does no good since it never gets to the fuel jets.

For this reason I like the oil injection system. IMHO, the oil in pre-mix won't get to the engine if the carburetors are clogged.

Since this is an '06, it may have sat for some time before your purchase like our '04. After your first couple trips, stuff may have gotten carried to the carbs.

An easy check for crap in your carbs is emptying the bowls at the brass drain screws. I suggest using a six sided wrench instead of a screwdriver and judiciously applying force. The brass screw is hollow with a hole partway up. If the fuel doesn't drain through the hole, you may have a load laying in bowls. Please check the condition of the "O" rings. If their in bad shape, after moving them you could find them leaking thereafter.

In any case, from a recent to new green horn, if your fuel lines are more than four years old, I suggest complete replacement with materials listed for low permeability and installing a 10 micron water separating fuel filter conveniently close to the outboard. The job takes less time than taking your boat to the shop and costs less than a failed trip. I also suggest getting Yamaha's service manual from their website. Even if you don't intend to tinker, the knowledge will avoid costs.

Good luck and keep us posted.