Echo ES-250ES Operator's Manual page 26

Maintenance and care
Cooling system maintenance
IMPORTANT
To maintain proper engine operating temperature, cooling air must pass freely through the cylinder fin area. This flow of air car-
ries combustion heat away from the engine.
Overheating and engine seizure can occur when:
 Air intakes are blocked, preventing cooling air from reaching the cylinder,
or
 Dust and grass build up on the out side of the cylinder. This build-up insulates the engine and prevents the heat from leaving.
Removal of cooling passage blockages or cleaning of cylinder fins is considered "Normal Maintenance". Any resultant failure
attributed to lack of maintenance is not warranted.
Tools required: Torx L-Wrench T27, Cleaning brush
Parts required: None, if you are careful.
Cleaning Grill
1. Brush accumulated debris from crankcase intake grill above
the fuel tank.
IMPORTANT
Do not over-tighten screws, otherwise mounting holes may be-
come stripped.
Cleaning Cylinder Fins
1. Disconnect spark plug lead from spark plug.
2. Remove spark plug.
3. Remove engine cover - 6 screws.
4. Loosely install spark plug to keep dirt out of cylinder.
5. Clean cylinder fins to allow cooling air to pass freely.
6. Reassemble parts in reverse order.
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