Husqvarna CR 50 / 2011 Workshop Manual page 23

ELECTRICAL SYSTEM (see also Section M)
Trouble
Spark plug fouls
easily
Spark plug electrodes
overheat
Ed. 01-09-2010
TROUBLESHOOTING
Cause
1. Mixture too rich
2. Dirty air filter
3. Worn piston rings
4. Worn piston or cylinder liner
1. Mixture too lean
2. Spark plug electrode gap too close
3. Heat rating too high
C.5
Remedy
Adjust carburettor setting
Clean
Replace
Replace
Adjust carburettor setting
Adjust
Replace with recommended
spark plug