Many call the engine the heart of the car. In fact, this is so. It is the motor that drives the car. ICE - the most expensive unit in any car. This node consists of several components. In addition to attachments, there is a block and a cylinder head. Each part has its own device and purpose. And today we will consider what the cylinder head is in the car, and why the car may not start after replacing its gasket.
Characteristic
The cylinder head stands for cylinder head . This is one of the most critical components in a car engine.
It is the cylinder head that is responsible for the control of fuel combustion, as well as for the exhaust gas exhaust.
Material
For many years, the head was made of the same material as the block. It was cast iron. But since the 80s, aluminum has replaced iron. It is from this material that 90% of all heads are made.
But not all engines have the ability to use aluminum cylinder head. The reason is the high temperature regime, in which deformation and thermal shrinkage of the metal is possible. Therefore, cast iron cylinder head is still used on such engines.
Device
Structurally, this node combines:
- Carter This is the block head housing.
- Spark plug. For them, special threaded holes are provided in the head. Candles are involved in ignition of the fuel mixture. On diesel engines, there are none.
- Nozzles Designed to supply fuel under pressure.
- Gas distribution mechanism. It consists of pulleys, a camshaft (maybe several) and valves. The latter are divided into two more types. So, there are cylinder head inlet and outlet valves. What is a valve machine? These elements are responsible for the timely injection of fuel and the removal of gases from the chamber, which are formed after ignition of the mixture.
- Combustion chamber. Each cylinder has its own. Its volume may be different, depending on the configuration of the cylinder head.
Between the head housing (what is the cylinder head in the car, we already found out) and the block must be placed asbestos gasket. Also in the design of the head there are fixed parts. They are installed by hot pressing in the cylinder head. What is this in a car? Fixed parts are valve seats. They are installed in the place where the head of the unit is in contact with a closed inlet or outlet valve. The saddles are a massive steel ring with a conical profile. If they malfunction, it is necessary to use a special tool for replacement. At home, such an operation is not performed.
How to install
The cylinder head is superimposed on the engine block above. It is attached using long bolts, or threaded rods. Since the landing area is large, the order of tightening the bolts is observed during installation. This will eliminate structural deformations and possible breakdowns, as well as gas breakthroughs.
Note that on in-line power units, the cylinder head covers the entire block. And on V-shaped motors, each row has its own head. But regardless of the type of layout of the cylinder block, a reinforced gasket is installed between the head and it. What is the cylinder head gasket in the car? This is a sealing element. The gasket is made of solid refractory material, which prevents the coolant from mixing with the exhaust gases and oil. Such a part is installed on all internal combustion engines. The exception is only some sports ICE. Here the head is polished so evenly and smoothly that its contours completely coincide with the cylinder block.
After replacing the cylinder head gasket, the machine will not start
Sometimes it happens that this element loses its tightness. In simple words, the gasket burns out. In this case, the car smokes when the engine is started. After replacing the cylinder head gasket, everything should return home. But if it is incorrect to set the marks of the gas distribution mechanism, then the car may not start at all. But when replacing or repairing the head of a block, you will certainly encounter such a mechanism as timing. It is driven by a belt or chain. Torque comes from the engine crankshaft. When dismantling a belt or chain, be sure to mark the location of the pulleys. When installing the timing gear, it is important to keep the marking accuracy. The slightest deviation may cause the machine to not start after replacing the cylinder head.
A more serious outcome is a failure of the valve timing. This is fraught with bent valves and damaged pistons. Having scrolled the starter only once, you can fly into a large amount of repair.
How to solve a problem
Consider the process of marking the example of a VAZ-2109 car. For work, we need a good flashlight, a slotted screwdriver, as well as keys for 17 and 19. After installing the tension pulley of the timing belt, we need to crank the camshaft pulley. You need to twist it until the mark coincides with the bar that is on the engine block. After that, leave the camshaft alone.
Go to the crankshaft. Here, too, have their own tags. On this shaft you need to make a bolt. This way labels are set faster. Rotate the shaft until they are in an upright position. Next, remove the rubber plug in the clutch housing. After that, we will have access to the flywheel. Why do we need him? Here, too, there is a mark, which ideally should coincide with the slot of the strap, which is attached to the cylinder block. If these designations coincide, then we correctly set the position of the timing elements. After that, you can safely install the belt. First, it is put on the crankshaft pulley, and then the camshaft.
Finally
So, we found out what the cylinder head is in the car. The head of the block is a very important unit in any engine. At the slightest of its malfunctions, problems arise with the operation of the entire power unit. If the gasket is broken in the engine, do not hesitate to replace it. Otherwise, the gases penetrate the cooling system and mix with antifreeze. And the latter will fall into the combustion chamber, because of which, when the engine is running, thick white smoke will come out of the exhaust.