Choke-A-Matlc Adjustment

TM 5-4240-501-148P CARBURETION Vacu-Jet, Pulsa-Jet Model Series 82500, 92500 and 94500 engines should be adjusted with fuel tank half full of gasoline. Initial Adjustment: Turn needle valve clockwise to close it. Then open 11/2 turns. This initial adjustment will permit the engine to be started and warmed up before making final adjustment. Final Adjustment: Place governor speed control lever in "FAST" position. Turn needle valve in until engine misses (clockwise lean mixture) then turn it out past smooth operating point until engine runs unevenly (rich mixture). Now turn needle valve to the midpoint between rich and lean so the engine runs smoothly. Next, adjust idle RPM. Rotate throttle counterclockwise and hold against stop. Adjust idle speed adjusting screw to obtain 1750 RPM. Release throttle engine should accelerate without hesitation or sputtering. If engine does not accelerate properly, the carburetor should be re- adjusted, usually to a slightly richer mixture. Breather and Fuel Intake Tubes Breather tube and fuel intake tube thread into the cylinder on Model Series 82000. Fuel intake tube is bolted to the cylinder on Model Series 92000, 94000, 110900 and 111900. See Fig. 38. Check for good fit or damaged gaskets to prevent air leaks or entry of dirt. Fig. 38 - Breather and Fuel Intake Tubes Choke-A-Matlc Adjustment The Choke-A-Matic feature was standard on Model Series 82000, 92500 (type nos. lower than 0600) 92900 (type nos. lower than 0500) engines. The remote control must be of the type in which the control wire moves out of the casing, when the control lever is moved from the stop position to the "Choke" or "Start" position. A minimum travel of 1-3/8" (34.9 mm) is required when the ! remote control is’ mounted, Fig. 39. Fig. 39- Remote Control To install remote control assembly proceed as follows: Remove the air cleaner and move the control lever to a position about midway between idle and fast. Then mount the remote control -with the casing clamp as shown in Fig. 40. Place control lever on equipment in fast (high speed) position. CONTROL MUST BE MOUNTED ON EQUIPMENT TO MAKE AN ACCURATE ADJUSTMENT. Lever "A" on carburetor should be just touching choke shaft at "B." Move casing "D" forward or backwards until correct position is obtained. Tighten screw "C." Recheck operation of controls after adjustment, Fig. 40. Fig. 40 - Choke-A-Matic Control (Typical) 13