2. Disconnect the connectors from the injectors.
3. Remove all glow plugs.
4. Cover the injector holes with a clean rag and after turning the crankshaft with the starter, check for foreign particles on them.
Caution: When turning the crankshaft with the starter, stay away from the injector holes.
Attention! If coolant, oil, fuel, etc. get into the cylinder during compression measurement (as a result of cracks), they will heat up and splash out of the hole under pressure, which is very dangerous.
5. Install and secure the compression tester to measure compression in diesel engines.
6. Turning the engine crankshaft with the starter, measure the compression in each cylinder, which should be at least 2000 kPa.
7. After measuring the compression in all cylinders, check that the compression difference between the cylinders does not exceed 400 kPa.
8. If the compression in any cylinder exceeds the maximum permissible value or the difference in compression between cylinders exceeds the maximum permissible value, then pour some engine oil into the injector hole of that cylinder and repeat the measurements.
9. If the compression has increased after adding oil, the cause of the malfunction is wear or damage to the piston ring and/or cylinder bore.
10. If the compression does not increase after adding oil, it means that the valve seat is burnt out or damaged, or there is a gas (pressure) leak through the cylinder head gasket.
11. Remove the compression gauge.
12. Install the glow plugs.
13. Connect the injector connectors.