Checking And Adjusting The Spark Plug; Spark Arrester (Optional Equipment) - OREC GRH537Pro Owner's Manual

3) Checking and adjusting the spark plug

Recommended Spark Plug:
BPR5ES(NGK) or W16EPR-U(DENSO)
NOTICE
When attaching a spark plug onto the engine, tighten by hand at first before tightening with a plug
●
wrench. If you start by using a plug wrench to screw in the spark plug, there is a danger of
cross-threading it.
A loose spark plug can overheat and damage the engine.
●
Overtightening the spark plug can damage the threads in the cylinder head.

4) Spark Arrester (optional equipment)

Your lawn mower engine is not factory-equipped with a spark arrester.
In some areas, it is illegal to operate an engine without a spark arrester. Check local laws and
regulations. An optional USDA approved spark arrester is available
The spark arrester must be serviced every 100 hours to keep it functioning as designed.
MUFFLER
MUFFLER
HEAT SHIELD
GASKET
SPARK ARRESTER
IDENTIFICATION
PLATE
1. Remove the spark plug with a plug
wrench and clean away any carbon
deposits on the electrodes with a wire
brush. Wipe away any moisture if present.
2.
Replace the spark plug with a new one if
the ceramic part has cracked or the
electrodes have suffered extensive wear
and tear.
3.
Please adjust the spark plug electrode
clearance to 0.7-0.8mm (0.028-0.031in).
1.
Allow the engine to cool and disconnect
the spark plug cap.
2.
Remove the muffler heat shield,
identification plate, muffler, and gasket.
3.
Remove the spark arrester from the muffler.
4.
Check for carbon deposits on the spark
arrester and the exhaust port. Brush
carbon deposits away. Be careful to avoid
damaging the spark arrester screen.
5.
Installation is the reverse of removal.
Tighten all hardware securely.
6.
Install the spark plug cap on the spark plug.
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