OREC Snow Bull Manuel D'utilisation page 24

WARNING
・ Never use gasoline or thinner as it is highly flammable
5.2.3 How to inspect and adjust the spark plug
When attaching a spark plug onto the engine, screw 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 risk of cross-threading it.
.
Remove the spark plug with a plug wrench and clean away
any carbon deposits on the electrode with a wire brush and
wipe away any moisture if present.
Replace the spark plug with a new one if the ceramic part
has cracked or the electrode shows extensive wear and
tear.
Please adjust the spark plug electrode clearance to 0.028-
0.031in (0.7-0.8mm).
Spark plug
W20EPR-U (DENSO)
-23-