The cylinder head gasket is replaced if it is damaged

The main signs of damage to the head gasket:

  • – insufficient compression, below 1 MPa (10 kgf/cm 2) in one or more cylinders;
  • - breakthrough of gases into the cooling system (seething, foaming of liquid in the radiator, rapid drop in the liquid level in the expansion tank in the absence of external leaks);
  • - ingress of coolant into the lubrication system (emulsion on the oil level indicator, stratification of oil drained from the crankcase - especially noticeable in a transparent container);
  • - oil entering the cooling system (oil film on the surface of the liquid in the expansion tank).

You will need: a torque wrench, a screwdriver, pliers, keys (regular and socket) "8", "10", "13", "17", head "E-Torx".

Remove the cylinder head cover (article - How to replace the cylinder head cover gasket VAZ-2123).

Drain the liquid from the engine cooling system (article - Replacing the coolant).

Depressurize the supply system.

How to replace a VAZ-2123 cylinder head gasket

Disconnect the throttle cable from the throttle assembly and the receiver.

How to replace a VAZ-2123 cylinder head gasket

Remove the bearing housing together with the camshaft from the cylinder head studs (article - Replacing the hydraulic bearings of the valve drive levers).

How to replace a VAZ-2123 cylinder head gasket

Remove the valve drive levers, unscrew all the lever hydraulic bearings from the holes of the cylinder head

How to replace a VAZ-2123 cylinder head gasket

remove the oil supply rail to the hydromounts

How to replace a VAZ-2123 cylinder head gasket

Disconnect the harness connectors from the throttle position sensor,

How to replace a VAZ-2123 cylinder head gasket

- idle speed controller,

How to replace a VAZ-2123 cylinder head gasket

- coolant temperature sensor of the engine management system

How to replace a VAZ-2123 cylinder head gasket

Disconnect the injector harness connector.

How to replace a VAZ-2123 cylinder head gasket

Disconnect the wiring harness from the knock sensor.

How to replace a VAZ-2123 cylinder head gasket

Pull the engine harness out of the way

Disconnect wires from spark plugs

How to replace a VAZ-2123 cylinder head gasket

Slide off the protective cap and disconnect the wire from the coolant temperature gauge sensor.

Unscrew the four nuts securing the downpipe to the cylinder head

How to replace a VAZ-2123 cylinder head gasket

Disconnect the downpipe from the exhaust manifold.

How to replace the VAZ-2123 cylinder head gasket

Remove the upper intake pipe brace bolt and loosen the lower brace bolt to move it aside

How to replace a VAZ-2123 cylinder head gasket

Loosen the fastening clamp and disconnect the canister purge hose from the throttle assembly

How to replace a VAZ-2123 cylinder head gasket

Loosen the mounting clamps and disconnect the cooling system radiator hoses from the cylinder head pipe

How to replace a VAZ-2123 cylinder head gasket

Loosen the clamp and disconnect the lower thermostat hose

How to replace a VAZ-2123 cylinder head gasket

Loosen the fastening clamp and disconnect the thermostat side pipe hose

How to replace a VAZ-2123 cylinder head gasket

Loosen the fastening clamp and disconnect the fluid supply hose to the heater radiator from the pipe of the cylinder head.

How to replace a VAZ-2123 cylinder head gasket

Unscrew the nuts of the fuel pipes and disconnect the fuel supply and drain lines.

How to replace a VAZ-2123 cylinder head gasket

Remove the top bolt securing the rear intake manifold strut, loosen the bottom bolt of the strut and move it aside

How to replace a VAZ-2123 cylinder head gasket

Remove the two nuts securing the starter heat shield

How to replace a VAZ-2123 cylinder head gasket

This is how the heat shield fastening nuts are located

Pull the shield aside.

How to replace a VAZ-2123 cylinder head gasket

Remove the chain tensioner (article - Replacing the camshaft drive chain tensioner).

Disconnect the power steering pump bracket from the engine (article - Replacing the camshaft drive chain tensioner shoe) and move it to the side along with the pump.

How to replace a VAZ-2123 cylinder head gasket

Remove the chain from the camshaft sprocket

Place it carefully on the tensioner shoe.

How to replace a VAZ-2123 cylinder head gasket

Make sure the chain does not disengage from the oil pump drive shaft sprocket.

It is best to tie the chain with wire.

How to replace a VAZ-2123 cylinder head gasket

Remove the ten cylinder head bolts.

The heads of the bolts are made on a turnkey basis "E-Torx", if necessary, you can use the head "13"

How to replace the cylinder head gasket VAZ-2123

Remove the block head.

Removing the block head is more convenient with an assistant, as it is quite heavy.

How to replace a VAZ-2123 cylinder head gasket

Remove the gasket located under the head.

How to replace a VAZ-2123 cylinder head gasket

To determine the cause of gasket failure, carefully inspect it.

How to replace a VAZ-2123 cylinder head gasket

On the edging of the gasket holes, traces of burnout will be visible between the combustion chambers of adjacent cylinders between the combustion chamber and the channel of the cooling system jacket or between the combustion chamber and the channel of the lubrication system.

Thoroughly clean the surface of the block from the remnants of the old gasket.

How to replace a VAZ-2123 cylinder head gasket

Remove foreign deposits from the channels of the cooling system jacket (if any).

The photo shows the removal of the old sealant.

Cylinder head bolt tightening order

The order of tightening the cylinder head bolts.

Install the cylinder head, centering it on the two guide bushings, screw in the bolts of its fastening and tighten them in four stages in a certain sequence (according to the figure):

  • - pre-torque 20.0 Nm (2.0 kgf m);
  • - tighten with a torque of 69.4–85.7 Nm (7.1–8.7 kgf m);
  • - turn 90°;
  • - finally turn it 90°.