1. Start the engine until it reaches the normal operating temperature.
2. Loosen all spark plugs for one to two seconds to start the engine (but do not let the engine start) for 5 to 10 seconds, which will disperse the dust of the spark plug base turnover and will not fall into the cylinder,
3, carefully remove all spark plugs, visual inspection of spark plugs can find many problems, such as: spark plugs have oil stains that the piston ring is broken or the valve guide is worn, spark plugs burn out that vacuum leakage.
4. Open the carburetor throttle valve completely to see if the result is so.
5. When using starter with motor, press the rubber fire-resistant cone of pressure gauge tightly against the spark plug hole.
6. Use the starter to drive the engine until it passes through 4 compression strokes. On each compression stroke, a slight guanidine row occurs in the measured value. Pay attention to the readings of the first stroke and the fourth stroke, make sure that the battery is fully charged, the starter is in good condition and drives the engine at normal speed. The speed of using starter with engine is too slow, which will lead to wrong results.
7. After reading the reading of the measuring instrument, pull down the deflation valve at the cone end to decompress.
