G
RASS
T
RIMMER
/B
RUSH
C
UTTER
O
PERATOR
'
S
M
ANUAL
27
SPARK PLUG
Level 2.
Tools required: Scrench (combination socket wrench and screw
driver supplied with unit), Feeler gauge (preferably a wire gauge), Soft
metal brush
Parts Required: Spark Plug NGK BPMR-7A
1. Remove spark plug and check for fouling, worn and rounded
center electrode.
2. Clean the plug or replace with a new one. DO NOT sand blast to
clean. Remaining sand will damage engine.
3. Adjust spark plug gap by bending outer electrode.
4. Tighten spark plug to 145 - 155 kg/cm (125 - 135 in. lb.).
COOLING SYSTEMS CLEANING
Level 3.
Tools required: Cross-head screwdriver, 3 mm hex wrench, pointed
wood stick
Parts Required: None if you are careful.
IMPORTANT
To maintain proper engine operating temperatures, cooling air
must pass freely through the cylinder fin area. This flow of air
carries combustion heat away from the engine.
Overheating and engine seizure can occur when:
- Air intakes are blocked, preventing cooling air from reaching the
cylinder.
- Dust and grass build up on the outside of the cylinder. This build up
insulates the engine and prevents the heat from leaving.
Removal of cooling passage blockages or cleaning of cooling fins is
considered “Normal Maintenance”. Any failure attributed to lack of
maintenance is not warranted.
1. Remove spark plug lead and throttle linkage end from the carbure-
tor swivel.
2. Remove the four screws that retain the engine cover (A). Two at
the top of the starter, two on either side of the front. Lift the cover
from the engine and lay to the front of the trimmer.
0.65 mm
(0.026 in.)
A