Motors drive the engine to rotate at 100-150R/MIN speeds for 3-5 seconds. Make the throttle fully opened and press the connection of the pressure gauge on the spark cold hole;. Five thread size: M10 x 1.0mm, M12 x 1.25mm, M14 x 1.25mm, M16 x 1.5mm, M18 x 1.5mm.
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