"Larry.... Bogging out when th
"Larry.... Bogging out when throttle is applied can be caused by improper carburetor needle valve settings or having the throttle butterflies open too soon in relation to the timing.
The throttle butterfly should just start to open when the scribe mark on the cam that is attached to the armature base is aligned with the center of the throttle cam roller.
The carburetor must be adjusted as follows:
(Carburetor Adjustments - Two Adjustable N/Vs)
(J. Reeves)
Initial settings are: Bottom high speed = seat gently, then open 1 turn out. Top slow speed = seat gently, then open 1-1/2 turns.
Setting the high and low needle valves properly:
NOTE: For engines that DO NOT have a shift selection, obviously there is no NEUTRAL position. Simply lower the rpms to the lowest setting to obtain the low speed needle valve adjustment.
(High Speed) Start engine (it will run pretty rough), shift into forward gear, take up to full throttle. In segments of 1/8 turn, waiting for the engine to respond between turns, start turning in the bottom high speed needle valve. You'll reach a point whereas the engine will either start to die out or spit back (sounds like a mild backfire). At that point, back out the needle valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest setting.
(Low Speed) Slow the engine down to where it just stays running. Shift into neutral. Again in segments of 1/8 turns, start to turn the top 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. Eventually you'll hit the point where the engine wants to die out or it will spit back. Again, at that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.
When you have finished the above adjustments, 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.
Adjust the float as follows:
(Carburetor Float Setting)
(J. Reeves)
With the carburetor body held upside down, the float being viewed from the side, adjust the float so that the free end of the float (the end opposite the hinge pin) is ever so slightly higher (just ever so slightly off level) than the other end. And when viewed from the end, make sure it is not cocked.
With the flywheel key aligned with the fiber rubbing portion of the points, they should be set so that a .020 gauge will pass thru but a .022 will not.
The flywheel nut must absolutely be torqued to 105 foot pounds, otherwise the key will shear.
The throttle rod linkage on the port side of the armature plate, the one that had a set screw in a brass link that presses up against the vertical throttle arm....... That is adjusted as follows:
Engine not running but in gear, turn the armature plate until it hits it stop BUT DO NOT apply any further throttle. Now, loosen that set screw so that the brass link can be moved. Take the play out of the rod (pressing it forward) just to the point where the throttle cam roller would start to move. At that point slide the brass link back against the vertical throlle arm clevis and tighten that set screw.
Adjusted in that manner, the rod does not apply pressure to the throttle cam roller until the full spark advance position has been accomplished, then applying further throttle results in applying direct pressure to opening the throttle butterfly."
