 printable version
Measurement of engine compression
NOTE Measurement of engine compression is recommended in the following cases: reduction of engine power, increased consumption of engine oil, increased fuel consumption. |
Warm up the engine to normal operating temperature, stop and wait for 10 minutes. Remove the spark plug coil Remove all spark plugs from the cylinder heads.
Insert the tip of the compression tester to the spark plug hole of the cylinder head and measure the engine compression (Fig. 2.73). Fully open the throttle. Consider indications compressometer Cranking the crankshaft of the engine starter.
NOTE When measuring the compression of the battery should be fully charged for correct measurement requires that the frequency of engine speed is not less than 300 min -1. |
Repeat operation of measure for each cylinder.
NOTE Duration of measurement of compression in each cylinder should be as small as possible. |
The amount of compression for the engine model L8: - Standard - 1750 kPa (17.855 kg / cm 2); - Minimum allowable - 1225 kPa (12.492 kg / cm 2). Difference between the measured values of compression in the cylinders of the engine (for a serviceable engine) must be no more than 196.1 kPa (1.99 kg / cm 2). The amount of compression for the engine model LF: - Standard - 1720 kPa (17.539 kg / cm 2); - Minimum allowable - 1204 kPa (12,277kg / cm 2). Difference between the measured values of compression in the cylinders of the engine (for a serviceable engine) must be no more than 196.1 kPa (1.99 kg / cm 2). The amount of compression for the engine model L3: - Standard - 1430 kPa (14.581 kg / cm 2); - Minimum allowable - 1000 kPa (10,197kg / cm 2). Difference between the measured values of compression in the cylinders of the engine (for a serviceable engine) must be no more than 196.1 kPa (1.99 kg / cm 2). If one or more of the value of the compression cylinders below the minimum, fill the cylinder through the spark plug hole a small amount of engine oil and re-measure the compression of this cylinder. If after the cylinder has been filled with oil, the amount of compression is increased, the most likely occurs wear or damage to the piston rings or the cylinder wall. If after the cylinder has been filled with oil, the amount of compression has not changed, it is likely there is a crash or a leaky valve landing in the saddle, or leak through the cylinder head gasket. Replace the spark plug. Replace the coil spark plugs.
| 
