To replace the cylinder head gasket, it is necessary to dismantle the head of the block, which is preceded by disconnecting the power supply and the sensors of the engine monitoring system, as well as the fuel supply and air inlet hoses.
The need to replace the cylinder head gasket may arise in the following cases:
1. Dismantling the cylinder head
The head gasket belongs to the running-in parts that are deformed under the influence of the microroughness of the connecting flanges of the cylinder block and the head of the block. When reassembling, the gasket will be slightly displaced from its original position, which may lead to a loss of tightness of the connection. Thus, any disassembly of the cylinder block involves changing the gasket.
2. Detection of leaks of engine oil or coolant
Leakage can be caused by mechanical damage to the gasket due to thermal deformations of the housing and cylinder head. To avoid engine failure, it is necessary to regularly carry out a visual inspection to identify this malfunction.
Preparing to replace the gasket
Before replacing the cylinder head gasket, the following sequence of steps must be performed:
1. De-energize the engine by disconnecting the battery terminals.
2. Disconnect the engine coolant temperature sensor.
3. Disconnect the engine oil pressure sensor and remove the thermostat.
4. Set the piston of the first cylinder to its initial position.
Gasket Replacement Technique
After the engine is de-energized and the monitoring system sensors are disconnected, you can begin to disassemble the block head and replace the gasket. The work must be carried out in the following sequence:
1. Disconnect the exhaust manifold inlet pipe from the exhaust manifold. Then dismantle the air cleaning filter.
2. Remove the front camshaft drive belt cover, then remove the cylinder block cover.
3. Remove the camshaft gear drive belt. Remove the camshaft gear by gently prying it off with two screwdrivers.
4. Disconnect the fuel supply hose, the air inlet flap drive rod cable, and the throttle control cable.
5. Disconnect the radiator inlet hose and the air heating inlet hose. Unscrew and remove the block head fixing bolts and remove the head. Then remove the head gasket to be replaced. Clean and degrease the surfaces of the connecting flanges.
6. Install a new gasket, then carry out p. 1-5 in reverse order. Then connect the sensors for monitoring the condition of the engine and turn on the power from the battery.
