2. Disconnect connectors from all fuel injectors.
Note. Disconnecting the connectors from the fuel injectors will disable the fuel injection system.
3. Remove all glow plugs.
4. When turning the crankshaft with a starter, cover all spark plug holes with a towel or cloth. After cranking the crankshaft with the starter, check for impurities adhering to the towel.
Warning
(1) When checking compression, do not stand in front of the glow plug holes.
(2) If during the measurement of compression in the cylinder (as a result of cracks) If coolant, oil, fuel, etc. gets in, these substances will heat up and be ejected under pressure from the glow plug hole, which can be dangerous.
5. Connect the compression tester to the glow plug hole of one of the cylinders.
6. Use a starter to turn the crankshaft of the engine and measure the compression.
The minimum allowable compression at a crankshaft speed of 250-400 min1: 2000 kPa
7. Check up a compression in other cylinders and write down the received indications. The pressure in all cylinders must be the same or differ no more than the permissible value.
Permissible compression difference in the engine cylinders: 400 kPa
8. If any cylinder pressure is too low, pour a teaspoon of clean engine oil into the cylinder through the glow plug hole and repeat steps 6 and 7.
(1) If the pressure increases after adding oil, the piston rings and/or cylinder are worn.
(2) If the pressure does not increase, then the cause is worn or burned valves or a blown cylinder head gasket. Low pressure in two adjacent cylinders almost always means that a head gasket is blown between them.
10. Screw in glow plugs.
11. Connect the connectors to the fuel injectors.