Hitachi CS 51EAP Manual Do Utilizador

15

MAINTENANCE, REPLACEMENT OR REPAIR OF 

THE EMISSION CONTROL DEVICES AND SYSTEM 

MAY BE PERFORMED BY ANY NON-ROAD ENGINE 

REPAIR ESTABLISHMENT OR INDIVIDUAL.

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.

Check that the air fi lter 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.

  When the engine is idling the cutting attachment 

must under no circumstances rotate. 

  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.

The air fi lter (40) must be cleaned from dust and dirt 

in order to avoid:

○ Carburetor malfunctions.

○ Starting problems.

○  Engine power reduction.

○  Unnecessary wear on the engine parts.

○  Abnormal fuel consumption.

Clean the air fi lter daily or more often if working in 

exceptionally dusty areas.

Remove the air fi lter cover (41) and the fi lter (40).

Rinse them in warm soap suds. Check that the fi lter 

is dry before reassembly. An air fi lter that has been 

used for some time cannot be cleaned completely. 

Therefore, it must regularly be replaced with a new 

one. A damaged fi lter must always be replaced.

40

41

Fig. 32

The spark plug condition is infl uenced by:

○  An incorrect carburetor setting.

○  Wrong fuel mixture (too much oil in the gasoline)

○  A dirty air fi lter.

○  Hard running conditions (such as cold weather).

These factors cause deposits on the spark plug 

electrodes, which may result in malfunction and 

starting diffi  culties.  If  the  engine  is  low  on  power, 

diffi  cult to start or runs poorly at idling speed, always 

check the spark plug fi rst. If the spark plug is dirty, 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. 

0.6 mm

0.024"(0.6 mm)

Fig. 33

  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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2012/03/19   16:33:46

2012/03/19   16:33:46