Turn off electrical consumers.
Check the condition of the air filter element (see section "Removal and installation the air filter").
Connect the devices for measuring the number of revolutions and the content of CO in accordance with their operating instructions; the air filter remains removed.
Note: The crankcase ventilation hose remains connected.
Start the engine at idle speed.
Check the ignition timing and adjust if necessary (see section "Checking and adjusting the ignition timing").
Check the tightness of the intake system. To do this, use a brush to cover all the joints of the intake device with gasoline. If you briefly increase the engine speed, air will be sucked in at the loose places. Localize and eliminate the leaks.
Warning: Do not inhale fuel vapors - poison! Do not allow gasoline to splash onto hot parts or the ignition system. Fire hazard!
Check the engine idle speed. For the specified value, see the table in the section "Ignition system").
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