Re: Johnson 6hp won't accelerate
Pelican.... If you have compression and spark on both cylinders, with both s/plugs firing, you may have overlooked something in the carburetor.<br /><br />The spark on that engine (with the plugs out) should jump a 1/4" gap with a strong blue flame on both cyls.<br /><br />The most commonly item overlooked when cleaning a carburetor is th brass fixed high speed jet which is located in the bottom center of the float chamber. Fuel must flow through that jet before it can flow to any other fuel passageway.<br /><br />Proper carburetor adjustment follows:<br /><br />(Carburetor Adjustment - Single S/S Adjustable Needle Valve)<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.
