Re: Evinrude 50hp carb settings
Aijmst.... The high speed jets are brass fixed jets located in the bottom center of the float chambers. Their only requirement is that they are absolutely clean.<br /><br />The slow speed adjustable needle valves must be adjusted as follows. Set both valves to the intial 1-1/2 turn out setting as mentioned below, then adjust the top carb first, then the bottom. Do not attampt to do both carbs at one time (a little here, a little there etc). After adjusting the bottom carb, you may need to go back and adjust again to fine tune.<br /><br />If the nylon needle valve retainer/bearing (just where the needle valve enters the carb isn't a RED one, replace it with the proper RED one (OMC #315232). The other color retainers are too loose and allow the needle valve to turn with the engine viberation.<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 />(Top Carb)<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 />Now repeat the above with the bottom carb.<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.
