Husqvarna 535RJ Operator's Manual page 25

MAINTENANCE
If the machine is low on power, difficult to start or runs poorly at idle speed: always check the spark plug first before taking
any further action. If the spark plug is dirty, clean it and check that the electrode gap is 0.5 mm. The spark plug should
be replaced after about a month in operation or earlier if necessary.
CAUTION! Always use the recommended spark plug type! Use of the wrong spark plug can damage the piston/cylinder.
Check that the spark plug is fitted with a suppressor.
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