Removing
Remove the cylinder head on a cold engine in the following order:
- relieve pressure in the fuel system;
- turn off the ignition and disconnect the wire «masses» from the storage battery;
- drain the coolant;
- remove the accessory drive belt;
- remove the generator;
- remove the cylinder head cover;
- remove the throttle assembly, injectors and fuel distribution line;
- remove the intake manifold;
- remove the exhaust manifold;
- remove the chain and sprockets from the camshafts;
- remove camshafts and pushers;
Pic. 3.54. Location of oil control valve (OCV) at the rear of the cylinder head
- remove oil control valve (OCV) (see fig. 3.54);
Pic. 3.79. Component connections to the cylinder head on the driver's side: 1 - hoses of the cooling system; 2 - radio interference suppressor; 3- «mass» the wire; 4 - camshaft position sensor; 5 - electrical connector of the oxygen sensor; 6 - coolant temperature sensor; 7 - oil pressure sensor
- mark and disconnect the cooling system hoses and all electrical wires and connectors from the cylinder head (pic. 3.79);
Pic. 3.84. Cylinder head bolt tightening sequence
- with a 10 mm hex wrench, in the reverse order to tightening, gradually loosen and then completely unscrew the cylinder head bolts (see fig. 3.84);
Pic. 3.80. Using a screwdriver to separate the head from the cylinder block
- remove the head from the cylinder block. If the head is too tight, use a screwdriver on the opposite side of the timing chain to separate the head from the cylinder block (pic. 3.80).
Installation
When replacing the block head, the cooling system must be filled with fresh coolant.
Pic. 3.81. Using a scraper to clean the mating surface of the cylinder block
The mating surfaces of the head and cylinder block must be perfectly clean. Use a hard plastic or wooden scraper to clean them (pic. 3.81). Be careful when cleaning as aluminum alloy is very easy to damage. Make sure that carbon deposits do not get into the channels of the lubrication and cooling system. This is especially important for the lubrication system, as deposits can block the oil supply to engine parts. Clean channels if necessary. If dirt gets into the cylinders, remove them from there with a vacuum cleaner.
Check the mating surfaces of the head and cylinder block: they should not have notches, deep scratches and other damage. Small defects can be eliminated by machining. In case of significant defects, the parts must be replaced.
Use a tap to clean the threads of the cylinder head bolt holes in the block. Clean the bolt holes in the block. Screwing a bolt into an oil-filled hole can rupture the block due to hydraulic pressure.
Install in the following order:
- install the parts and assemblies that were removed from the cylinder head;
- check that the guide bushings are installed in the cylinder block;
Attention! Remove a new cylinder head gasket from the packaging immediately before installation.
Pic. 3.82. Marking location (1) gaskets
- install the gasket on the guide bushings, while the inscription «top» should be directed towards the head, and the marking 1 (pic. 3.82) gaskets are located on the rear side of the engine;
Pic. 3.83. Places for applying a layer of RTV sealant to the cylinder head gasket
- Apply a 2.5-3.0 mm thick layer of RTV Sealant to the gasket at the locations shown in fig. 3.83.
- install the head on the cylinder block without disturbing the position of the gasket;
- apply a thin layer of engine oil to the threads and under the bolt heads, insert the cylinder head bolts and tighten them by hand;
- in the sequence shown in fig. 3.84, tighten the cylinder head bolts in two stages:
- 1st - tighten with a torque of 79 Nm;
- 2nd - tighten by an angle of 90°.
In the future, additional tightening of the cylinder head bolts is not required.
Further installation of the cylinder head is carried out in the reverse order of removal, taking into account the following.
Check and, if necessary, adjust the valve clearances.
Fill with coolant.
Install a new oil filter and fill the engine with engine oil.
Start the engine and check for leaks.