Re: Carb Leak (need help)
That's really the low speed idle mixture, but we know what your talking about. If you pull off the plastic piece (link), you'll see a packing nut. Behind this packing nut are packing washers. You can try tightning the nut a bit. This will compress the packing washers and should seal the shaft of the needle valve. The more you tighen the nut, more friction will be needed to adjust the needle valve. After you have tightned the packing nut, center the 'Slow speed Idle knob" (lower right knob), and snap the plastic 'link' back on the shaft end.<br /><br />After you get the leak fixed do this:<br />Courtesy of Joe Reeves, Thanks Joe! (again...)<br /><br />Depending on which carb you have, pick one of the following.<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<br />turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to<br />respond. As you turn the valve in, the rpms will increase. Lower the rpms again to<br />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<br />(sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4<br />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<br />them again unless the carburetor fouls/gums up from sitting, in which case you<br />would be required to remove, clean, and rebuild the carburetor anyway.<br />--------------------------------------------------<br />(Carburetor Adjustments - Two Adjustable N/Vs)<br /><br />Initial settings are: Bottom high speed = seat gently, then open 1 turn out. Top slow<br />speed = seat gently, then open 1-1/2 turns.<br /><br />Setting the high and low needle valves properly:<br /><br />NOTE: For engines that DO NOT have a shift selection, obviously there is no<br />NEUTRAL position. Simply lower the rpms to the lowest setting to obtain the low<br />speed needle valve adjustment.<br /><br />(High Speed) Start engine (it will run pretty rough), shift into forward gear, take up to<br />full throttle. In segments of 1/8 turn, waiting for the engine to respond between turns,<br />start turning in the bottom high speed needle valve. You'll reach a point whereas the<br />engine will either start to die out or spit back (sounds like a mild backfire). At that<br />point, back out the needle valve 1/4 turn. Within that 1/4 turn, you'll find the<br />smoothest setting.<br /><br />(Low Speed) Slow the engine down to where it just stays running. Shift into neutral.<br />Again in segments of 1/8 turns, start to turn the top needle valve in. Wait a few<br />seconds for the engine to respond. As you turn the valve in, the rpms will increase.<br />Lower the rpms again to where the engine will just stay running. Eventually you'll hit<br />the point where the engine wants to die out or it will spit back. Again, at that point,<br />back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed<br />setting.<br /><br />When you have finished the above adjustments, you will have no reason to move<br />them again unless the carburetor fouls/gums up from sitting, in which case you<br />would be required to remove, clean, and rebuild the carburetor anyway.<br /><br />--------------------<br />Joe (30+ Years With OMC)
<br />
