Re: 1967 18 HP Evinrude sluggish top end
Mike... No offense intended but if the engine is a manual throttle engine whereas you must sit in the extreme back of the boat, the engine might be okay.... then again it might not. Just a factor to consider.<br /><br />The points should be set where a .020 feeler gauge will go thru but a .022 will not.<br /><br />If the armature plate which holds the points wobbles, the point setting will change as the armature plate revolves. Should this wobble exist, try the following.<br /><br />(Magneto Armature Plate)<br />(J. Reeves)<br /> <br />If the armature plate has a a loose fitting, wobbling motion (the plate that the points, coils etc are attached to), it is usually caused by a slightly worn support ring. This allows the point setting to change erratically as the armature plate turns.<br /> <br />The cure is to remove the armature plate so that the support which is attached to the powerhead with 4 screws is visible. Then, with a screwdriver and hammer, or some tool of your choosing, and looking straight down at the support ring, make an indentation at what would be called the 12, 3, 6, and 9 O'clock positions. Install the armature plate and check for a smooth turning wobble free movement.<br /><br />You may need to do that procedure a few times to obtain the proper fit (not too tight, not too loose), but it's worth the effort.<br /><br />The sp[ark on that engine should jump a 1/4" gap with a strong blue lightning like flame... a real SNAP! If it does not, find out why.<br /><br />The carburetor adjustment follows:<br /><br />(Carburetor Adjustment - Single S/S Adjustable Needle Valve)<br />(J. Reeves)<br /><br />Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.<br /> <br />Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.<br /> <br />Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting. <br /> <br />Note: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.<br /><br />When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.<br /><br />If none of the above helps, check the size of the propeller and if possible, drop to a lower pitch prop.
