MAINTENANCE

MAINTENANCE, REPLACEMENT OR REPAIR OF THE EMISSION CONTROL DEVICES AND SYSTEM MAY BE PERFORMED BY ANY NON-ROAD ENGINE REPAIR ESTABLISHMENT OR INDIVIDUAL.

Carburetor adjustment (Fig. 31)

T

H

L

Fig. 31

In the carburetor, fuel is mixed with air. When the engine is test run at the factory, the carburetor is adjusted. A further adjustment may be required, according to climate and altitude. The carburetor has one adjustment possibility:

T = Idle speed adjustment screw.

Idle speed adjustment (T)

Check that the air filter is clean. When the idle speed is correct, the cutting attachment will not rotate. If adjustment is required, close (clockwise) the T-screw, with the engine running, until the cutting attachment starts to rotate. Open (counter-clockwise) the screw until the cutting attachment stops. You have reached the correct idle speed when the engine runs smoothly in all positions well below the rpm when the cutting attachment starts to rotate.

If the cutting attachment still rotates after idle speed adjustment, contact Hitachi Authorized Service Centers.

WARNING

When the engine is idling the cutting attachment must under no circumstances rotate.

NOTE

Do not touch the High speed adjustment (H) and the Low speed adjustment (L).

Those are only for Hitachi Authorized Service Centers.

If you rotate them, it will cause a serious damage to the machine.

Air filter (Fig. 32)

The air filter (40) must be cleaned from dust and dirt in order to avoid:

○ Carburetor malfunctions. ○ Starting problems.

○ Engine power reduction.

English

○ Unnecessary wear on the engine parts. ○ Abnormal fuel consumption.

Clean the air filter daily or more often if working in exceptionally dusty areas.

Remove the air filter cover (41) and the filter (40). Rinse them in warm soap suds. Check that the filter is dry before reassembly. An air filter that has been used for some time cannot be cleaned completely. Therefore, it must regularly be replaced with a new one. A damaged filter must always be replaced.

41

40

Fig. 32

Spark plug (Fig. 33)

The spark plug condition is influenced by: ○ An incorrect carburetor setting.

○ Wrong fuel mixture (too much oil in the gasoline) ○ A dirty air filter.

○ Hard running conditions (such as cold weather). These factors cause deposits on the spark plug electrodes, which may result in malfunction and starting difficulties. If the engine is low on power, difficult to start or runs poorly at idling speed, always checkthesparkplugfirst.Ifthesparkplugisdirty,clean it and check the electrode gap. Readjust if necessary. The correct gap is 0.024” (0.6 mm). The spark plug should be replaced after about 100 operation hours or earlier if the electrodes are badly eroded.

0.024"(0.6 mm) Fig. 33

NOTE

In some areas, local law requires using a resistor spark plug to suppress ignition signals. If this machine was originally equipped with resistor spark plug, use same type of spark plug for replacement.

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