Cylinder head gasket (Audi A4 B6)

Loss of power, coolant and oil loss, no compression in two adjacent cylinders, coolant in the engine oil or oil in the coolant most likely indicate a defective cylinder head gasket. In this case, it is necessary to remove the engine and dismantle the cylinder head. This work, which requires such special tools as the VW-3036 counter support, the VW-3450 or HAZET 2571 guide pin, the HAZET 798-5 band clamp pliers, as well as the support device or the VAG 1202 A workshop crane, should be performed in a specialized workshop. At the same time, in order to be able to remove the cylinder head cover, it is necessary to remove the units, disconnect the pipes, drain the coolant, remove the vacuum hoses, unscrew the front exhaust pipe from the manifold, remove the poly V-belt and toothed belt, lift the engine and, depending on the engine, perform a number of other complex work operations.

However, if you still have to change the cylinder head gasket, the following rules must be followed:

Rules for replacing the cylinder head gasket

The cylinder head mounting screws must be unscrewed and screwed in in the specified sequence.





The new cylinder head gasket is removed from its packaging immediately prior to installation. The gasket must be handled with extreme care to avoid damage.

The cylinders should be plugged with clean rags to prevent dirt and abrasives from getting into the space between the cylinder working surface and the piston. Such particles should also not get into the coolant.

There should be no oil or coolant in the mounting screw holes (wrap a screwdriver in a piece of cloth and insert it into the holes).

Thoroughly clean the sealing surfaces of the cylinder head and cylinder block. Do not scratch the surfaces! If sandpaper is used, the grain size should be at least 100.

The head must be centered; special centering pins (arrows) are provided for this purpose.



The new gasket should have the same marking as the old one. Depending on the piston protrusion, gaskets of different thicknesses are installed, so be sure to pay attention to the gasket marking.

The new cylinder head gasket is placed on the centering pins so that the inscription can be read from the intake side. Then install the cylinder head, insert and screw in the screws by hand. The screws are then tightened in the specified sequence (starting with screw #1 and ending with screw #10) in two stages. In the first stage, the screws are tightened with a torque wrench to 40 Nm, in the second they are tightened by another 180° (half a turn) with a non-adjustable wrench.



If the cylinder head is replaced, then all the coolant must also be changed.

Fault indicator

(The original article is available on the website AUDIMANUAL.RU)