No High Speed

[fisheagle]

I would appreciate advice regarding a Lightwin 3 Evinrude Model 3018 that I recently inherited. This outboard has been stored since 1982. The problem is high speed - it has none. The motor starts fine and runs well at low speeds. However, when I initially ran the motor, it would not achieve higher speed or rpm when throttling up. The next day that I ran the motor it ran ok at high speed for awhile. Then it reverted back to it's inability to throttle up to high speed/rpm. I am running 50:1 fuel ratio. As far as fuel/air adjustments, the low speed needle adjustment seems fine. Turning the high speed adjustment needle does not create high speed results, but will stall the motor at extreme adjustments. Both cylinders seem to have spark. Should I rebuild the carburetor or could something else cause this problem?

 

[Paul Moir]

Re: No High Speed

Fisheagle - first, start by verifying your spark. Carefully look over the spark plug wires checking for cracks or wear throughs. Also, test spark over a large gap. That ignition system should be able to throw 3/8" long sparks at cranking speed. Check both wires.<br />It is very common on these engines to have what appears to be good spark that fails as you throttle up causing exactly the problem you're describing. The ignition coils get cracks from age and arc over as the rpms pick up and the voltage on the magneto increases.<br />Second, do not use 50:1 in that engine. Your engine is a 1956 model and it should be run at 24:1 - it really needs it. Even the 3hp engines that were rated for 50:1, a case can be made for extra oil!<br />You'll also need to replace at least the water pump impeller. They go bad just sitting there, and are critical components. On the 3hp, changing it is easy. Just be really careful not to pull up on the driveshaft when you have the impeller housing off. It'll pull right out of the lower unit.<br />You should really get a manual. Iboats aftermarket manual is pretty good. You may be able to find one at your local library if your unwilling to purchase one. The OEM ones, though pricey, are the best:<br />TheOutboardWizard<br />Mastertech<br />Marine Engine<br />Ken Cook <br /><br />In the mean time, have a look at this article:<br />3hp Tune Up article. <br />(EDIT - the hosting site seems to be down right now. Try this slower link:<br /> Slow tuneup article )<br /><br />Those 3hp engines are really terrific little outboards. It's certainly worth getting your's tuned up.<br /> Joe Reeves post on setting up the carb controls

 

[Xcusme]

Re: No High Speed

Stored since '82?? Replace the water pump/impeller. Perhaps your dropping a cylinder, bad coil?? Trash in carb?? Adjusting the high speed mixture adjustment is best done on the lake, under a full load.

 

[fisheagle]

Re: No High Speed

Originally posted by Paul Moir:<br /> Fisheagle - first, start by verifying your spark. Carefully look over the spark plug wires checking for cracks or wear throughs. Also, test spark over a large gap. That ignition system should be able to throw 3/8" long sparks at cranking speed. Check both wires.<br />It is very common on these engines to have what appears to be good spark that fails as you throttle up causing exactly the problem you describe you have. The ignition coils get cracks from age and arc over as the rpms pick up and the voltage on the magneto increases.<br />Second, do not use 50:1 in that engine. Your engine is a 1956 model and it should be run at 24:1 - it really needs it. Even the 3hp engines that were rated for 50:1, a case can be made for extra oil!<br />You'll also need to replace at least the water pump impeller. They go bad just sitting there, and are critical components. On the 3hp, changing it is easy. Just be really careful not to pull up on the driveshaft when you have the impeller housing off. It'll pull right out of the lower unit.<br />You should really get a manual. Iboats aftermarket manual is pretty good. You may be able to find one at your local library if your unwilling to purchase one. The OEM ones, though pricey, are the best:<br />TheOutboardWizard<br />Mastertech<br />Marine Engine<br />Ken Cook <br /><br />In the mean time, have a look at this article:<br />3hp Tune Up article. <br />(EDIT - the hosting site seems to be down right now. Try this slower link:<br /> Slow tuneup article )<br /><br />Those 3hp engines are really terrific little outboards. It's certainly worth getting your's tuned up.<br /> Joe Reeves post on setting up the carb controls

 

[fisheagle]

Re: No High Speed

Thanks Paul! I appreciate the advice.