To Adjust Carburetor, To Replace | Husqvarna ST724 instruction

SERVICE AND ADJUSTMENTS

TO ADJUST CARBURETOR

The carburetor (See III.33) has been pre-set at the factory and readjustment should not be necessary. How- ever, if the carburetor does need to be adjusted, proceed as follows:

●Close the high speed adjusting screw by hand.

●Do not over tighten.

●Then open it 1-1/4 to 1-1/2 turns.

●Close the idle adjusting screw by turning clockwise by hand. Do not over tighten.

●Then open it 1-1/4 to 1-1/2 turns.

●Start the engine and let it warm up.

●Set the throttle control to RUN. Adjust the high speed adjusting screw in until the engine speed or sound alters. Adjust the screw out until the engine speed sound alters. Note the difference between the two limits and set the screw in the middle of the range.

●Let the engine run undisturbed for 30 seconds after each setting to allow the engine to react to the previous adjustment.

●Set the throttle control to SLOW. Adjust the idle adjusting screw in until the engine speed drops, then adjust the screw out until the engine speed drops. Note the difference between the two limits and set the screw in the middle of the range.

●If the engine tends to stall under load or does not accelerate from low speed to high speed properly, adjust the high speed screw out in 1/8 turn incre- ments until the problem is resolved. Let the engine run for 30 seconds between settings.

IMPORTANT: NEVER TAMPER WITH THE ENGINE GOVERNOR, WHICH IS FACTORY SET FORPROPER ENGINE SPEED. OVER-SPEEDING THE ENGINE ABOVE THE FACTORY HIGH SPEED SETTING CAN BE DANGEROUS. IF YOU THINK THE ENGINE -GOV- ERNED HIGH SPEED NEEDS AD- JUSTING, CONTACT YOUR NEAR- EST AUTHORIZED SERVICE CEN- TER, WHICH HAS THE PROPER EQUIPMENT AND EXPERIENCE TO

MAKEANY

NECESSARY ADJUSTMENTS. A

DISTRIBUTOR'S LIST IS ON THE

INSIDE BACK COVER OF THIS MANUAL.

TO ADJUST OR REPLACE THE SPARK PLUG

If you have difficulty starting your snow thrower, you may need to adjust or replace the spark plug. Follow the instructions below.

Replace the spark plug if the electrodes are pitted or burned or if the porcelain is cracked.

TO ADJUST:

●Clean the spark plug by carefully scraping the electrodes (do not sand blast or use a wire brush).

●Be sure the spark plug is clean and free of foreign material. Check the electrodes gap (See III.34) with a wire feeler gauge and reset the gap to .030 inch if necessary.

TO REPLACE:

●Remove the spark plug wire.

●Clean the area around the plug base to prevent dirt from entering the engine when the plug is removed.

●Remove the spark plug. If it is cracked, fouled or dirty, it must be replaced.

●Set the gap between the electrodes of the new spark plug at .030 inch. Next, install the spark plug in the cylinder head. Tighten the plug to 18 to 23 foot pounds. If you do not use a torque wrench, tighten the plug firmly (See III.34).