Husqvarna PF 21 用户手册

28 – 

English

Check that the level of the battery acid lies between the 
markings. Top up the cells with distilled water only.

The engine is equipped with an electronic ignition system. 
Only the spark plug requires maintenance.

For recommended spark plug, see Technical data.

1

Remove the ignition cable shoe and clean around the 
spark plug.

2

Remove the spark plug with a 3/4” (19 mm) spark plug 
socket wrench.

3

Check the spark plug. Replace the spark plug if the 
electrodes are burned or if the insulation is cracked or 
damaged. Clean the spark plug with a steel brush if it is to 
be reused.

4

Measure the electrode gap with a gapping tool. The gap 
should be 0.75 mm/0.030”. Adjust as necessary by 
bending the side electrode.

5

Reinsert the spark plug, turning by hand to avoid 
damaging the threads.

6

Tighten the spark plug, once it touches the seating, with 
the spark plug spanner. Tighten the spark plug so that the 
washer is compressed. A used spark plug should be 
turned 1/8 of a turn from the seated position. A new spark 
plug should be turned a 1/4 turn from the seated position.

7

Replace the ignition cable shoe.

Keep the engine and muffler free from grass cuttings and dirt.  
Grass cuttings steeped in petrol or oil on the engine can 
increase the fire risk and impair cooling.

Allow the engine to cool before cleaning. If the dirt is mixed 
with oil, remove it using a degreasing agent otherwise just 
water and a brush.

Grass cuttings around the muffler dry quickly and constitute a 
fire risk. Brush or wash them off when the muffler is cold.

Fitting the wrong spark plug type can damage the engine.

Inadequately tightened spark plugs can cause overheating 
and damage the engine. Tightening the spark plug too 
much can damage the threads in the cylinder head.