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 / cm2) 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).
To replace the gasket, you need to remove the cylinder head with the reservoir and exhaust manifold.
If the cylinder head is removed from the engine installed on the car, you must first drain the coolant (see "How to replace the engine coolant of a UAZ Patriot car").
You will need: keys "for 12", "for 13", "for 17", hexagons "for 6", "for 12", a screwdriver.
Disconnect the wire from the negative terminal of the battery.
Drain the cooling system.
Remove the generator.
Remove the nuts securing the exhaust pipe to the exhaust manifold (Fig. 1).
Remove the bolt that secures the exhaust pipe to the bracket on the gearbox (Fig. 2) and move the exhaust pipe away from the exhaust manifold.
Disconnect the wiring harness connector from the mass air flow sensor (fig. 3).
Disconnect the throttle position sensor harness connector (fig. 4).
Disconnect the crankshaft position sensor harness connector (fig. 5).
Loosen the air pipe clamp, remove the pipe and move it to the side.
Disconnect the end of the cable from the throttle actuator sector (fig. 7).
Loosen the end of the cable sheath to the bracket (fig. 8).
Remove the end of the cable sheath from the bracket and move the cable to the side (Fig. 9).
Remove the cylinder head cover (see "Replacing the cylinder head cover gasket ZMZ-409").
Remove the upper chain tensioner
Remove the camshafts (see "Removing and installing ZMZ-409 camshafts").
Disconnect the engine harness pads from the injectors (Fig. 10).
Unscrew the front nut securing the receiver (Fig. 11) and remove the “mass” wires from the studs.
Disconnect the wiring harness connector from the idle speed control (fig. 12).
Unscrew the rear nut securing the receiver (Fig. 13), remove the holder 2 of the fuel supply hose and the second “mass” wire 1 of the harness from the stud, and then set aside the wiring harness.
Loosen hose clamps 1 on the throttle assembly and disconnect hoses 2 and 3 (Fig. 14).
Unscrew the nuts of the supply and drain fuel lines (Fig. 15) and move the lines to the side.
Remove the bolts securing the upper chain damper (Fig. 16) and remove the damper.
Remove the oil level indicator (dipstick).
Remove the rightmost exhaust manifold nut (fig. 17).
Remove the coolant line bracket from the stud (fig. 18).
Sequence of tightening the cylinder head bolts (Fig. 19).
Remove the bolts 1 (Fig. 20) securing the cylinder head in reverse tightening sequence, remove the cylinder head and remove the gasket.
Thoroughly clean the mating surfaces of the head and cylinder block from carbon deposits, remnants of the old gasket and sealant.
Lubricate the new gasket on both sides with a thin layer of graphite grease, and at the point of contact with the front cover of the block with heat-resistant adhesive-sealant.
Lay the gasket on the cylinder block, making sure that the locating sleeves of the block fit into the corresponding holes in the gasket.
Install the block head in the reverse order of removal.
Tighten the block head bolts in the order shown in fig. 19.
Tighten the cylinder head bolts in two steps:
- 1st stage - 40–60 Nm (4.0–6.0 kgf m);
- 2nd stage - 130-145 Nm (13.0-14.5 kgf m)