Re: How much should '60's motors smoke?
Hi Tinker<br />First of all it's hard to say how much smoke you have or have not sitting here. Any two-stroke motor smokes, and should. Smoke is a good thing. Most outboard motors exhaust out the lower leg, under water. When the boat is under way there is a vacuume formed under water behind the lower unit. This helps suck exhaust from the motor and muffles the noise. When the boat is not moving,(at the dock or test tank) the water is basicly plugging off the exhaust pipe (like stuffing a potato in your car exhaust). This is why an exhaust relief port is provided (an opening above the water line and out the bottom.Agian when the boat it moving the vacuume created sucks most of the gas past the relief port . When testing in a tank there is no where for the exhast to go. And since most folks use trash cans or barrels there is not enough water for to create this vacuume affect, if there was it still wouldn't matter, your not going anywhere and neither is the smoke. Shops use tanks that are equipt with fans that draw off most of the exhaust and pipe it outside. If you are working on/adjusting and motor and have no breeze, set up a small fan so your work area is more comfortable. This is also a prudent idea when tuning air cooled motor cycles 2 or 4 stroke (helps cool the motor). Now you can have too much smoke. More often than not this is due more to an over rich air/fuel mixture (carb out of adjustment) rather than too much oil. Of course more oil more smoke. Lets say the your motor is supose to run 50:1. I you doubled the oil to 25:1 you would not notice twice as much smoke. This assumes the motor is properly adjusted in the first place. Do not adjust a motor so lean it dosen't smoke a little. Smoke is your freind. When you start an outboard cold, you choke/prime it. This procedure draws a super rich fuel mix into the engine. The engine has no fuel in it, it is how ever full of air. When all this air and super rich fuel get all mixed up in there and lit off, your going to have more smoke for a few miniutes, it doesn't matter how new or old your 2-motor is. Smoke is part of motor language. It is one way your motor has to talk to you. Get to know you engines and talk back to them once in a while. Be nice to them.