Re: Info on Johnson 20 Seahorse Motor.
Use what is called "HiVis" (80/90w) which is available at Wal*Mart, K-Mart etc at a reasonable price. Of course it is also available at your local dealership but at a slightly higher price.<br /><br />DO NOT remopve the "Philips Screw" that might be located in the skeg of the lower unit. That philips screw is a long shoulder type screw which is a pivot point for the internal shift lever. The drain/fill and vent screws are the large regular slotted screws. Fell the unit "From The Bottom" until the oil flows out of the upper vent hole.<br /><br />The rich and lean linkage can be disconnected at the carburetor slow speed needle valve momentarily in order to adjust the carburetor properly, as follows. If this adjustment fails to correct any possible carb problem, you'll need to clean the carb. This adjustment controls the actual fuel flow through the carburetor and has nothing to do with the choke opperation.<br /><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 />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 /><br />The fast/slow/stop indicators on the twist grip are simply for reference (which way is fast etc). Ignore them.<br /><br />Start sequence: Engine in neutral, pump primer bult until it's hard (check for leaks), pull out choke, turn tiller (throttle) handle towards fast until it stops (there's a stop on the mag plate that when in neutral, it will not allow the throttle to obtain the full throttle position), crank the engine.<br /><br />When it starts, push in the choke so that the engine doesn't flood out.