Do-it-yourself car repair in most cases allows not only to save significantly, but also to prevent serious malfunctions in a timely manner. In vehicles equipped with 16-valve cylinder head, hydraulic compensators can knock. You can fix the situation. Flushing lifters will help. Let's see how this is done.
Hydrocompensators: what it is and where they are
These elements are an important part of the gas distribution mechanism. You can find these hydraulic lifters directly above the valve. To be more precise, then under the camshaft cam.
This part looks like a cylinder. Inside it is a special check valve, a plunger pair, as well as a spring. Special channels are made in the walls of the hydraulic compensator. They serve to circulate the oil.
Function of hydraulic lifters in the engine
During the operation of the car engine, each of its parts is heated to high temperatures. Valves are also heated. If we recall the course of physics, then at the time of heating the body expands. This means that the gaps between the valves and the rocker arms in the valve mechanism will inevitably decrease.
On older cars with simple engines, valve clearances were manually adjusted. This is a simple job, but it requires certain skills, knowledge and a set of tools to complete it. If the clearances are not adjusted correctly or at the wrong time, certain problems will appear. One of them is a knock that is familiar to every owner of such a car. This noise suggests that the gaps are too large.
Small gaps also led to certain problems. Because of this, the valve did not close properly. Mechanisms had to be adjusted quite often, since during the operation of the motor the settings were constantly getting lost.
Through the introduction of hydraulic lifters, the car owner no longer needs to adjust valve clearances. Now this is done automatically. In other words, the presence of hydraulic compensators in the motor design greatly simplifies the process of servicing the engine, increases the valve mechanism resource, and provides the motor with more elastic and stable operation.
Signs of malfunction of the hydraulic compensator
One of the characteristic symptoms is a metal knock during engine operation. Especially clearly, these noises can be heard at the moment of gaining speed. A clatter will be heard. Most often, among the causes are pollution of the hydraulic compensator from the inside. Therefore, he cannot timely select thermal gaps.
Cold engine sound
You can also hear the sound of the hydraulic compensator on the cold. After the engine warms up, the sound disappears. But it may persist. If these sounds occur only on a cold engine, then this is not so scary. There are several reasons that are completely removable with your own hands.
Wrong oil selection
Noises on a cold engine can happen for banal reasons - higher viscosity oil is poured into the engine. Sometimes it does not meet the requirements of the manufacturer or has exhausted its resource.
When buying a car "with hands", it is recommended to change the oil immediately to a new one. Also, before replacing, flush the engine from the inside. This is done simply with your own hands in a garage environment. Experts recommend pouring semi-synthetic fluids. If the oil has changed, but the knock of the hydraulic compensator on the cold is still audible, it is worth considering other reasons.
Valves
Hydrocompensator valves can sometimes fail. In this case, the oil, when the engine is not running, will leak due to loose connections. Air will enter the system, which then disappears when oil is displaced by oxygen.
Inlet
It happens that the inlet on the hydraulic compensator is clogged. The hole is responsible for supplying oil to the part. When the motor heats up, the temperature and oil increase. The gaps expand and the oil begins to flow as expected. However, the various viscous elements then clog the inlet again. You can replace the oil with one whose viscosity is less. Cleaning the engine will also help . Along with these measures, washing the hydraulic compensator is also effective.
Oil filter
If this element has not changed for a long time, then this is also one of the reasons why the hydraulic compensator will knock on a cold engine. Along with heating the engine and oil, it will begin to flow normally through the filter. But more often this does not happen. Elements knock even on a warmed motor. An oil change along with the filter will help to solve the problem.
How to check the performance of hydraulic lifters
And how to check the hydraulic compensators at the VAZ? By removing the valve cover, you can access these elements. Next, each of them is pressed with a finger. If the part is out of order, it will be sunk without effort.
In this situation, you cannot restore the item. Only a replacement will help. How much it costs to replace the hydraulic lifters depends on the model of the car and engine. So, for most VAZ models, this operation will cost five thousand rubles. If imported spare parts are selected, then the price will be 7-10 thousand. Naturally, this is not an exact cost - specific figures depend on the region and brand of car. If the mechanism is recessed only from serious effort, then flushing of hydraulic compensators will help to restore efficiency and remove knock.
Rinse preparation
So, if there is a knock, but the HA is in good condition, then you should rinse them. To do this, remove the air filter and the cylinder block cover. Also dismantle the axis of the rocker arm, where the hydraulic lifters are located. They are carefully removed from the seats. Before washing, prepare three containers, which together have a volume of about five liters.
Before flushing, let the car stand in the garage for a day. During this time, the oil drains from the HA to the sump. Flushing the hydraulic lifters will be successful and effective if it is carried out indoors, where there is no dust and wind. As washing liquid, kerosene or A-92 gasolines can be used. But you can use specialized products.
Instructions, procedure
After dismantling the compensators, they are cleaned from the outside with brushes with non-natural bristles. Then the parts are washed in the first tank, where the liquid for washing the hydraulic lifters was pre-filled. Each element is lowered into the container and several times the wire is pressed on the check ball valve. Then press on the plunger.
If the plunger stroke has become easy, then the compensator is washed in the second tank. However, before this, all liquid is drained from the compensator. To do this, just squeeze the ball. Oil circulation channels are flushed using a syringe.
An important point in performing this operation is checking the mechanisms. So, lowering the compensator in the third tank with a cleaning agent, they collect liquid into the part.
Then the part is lowered and pulled out so that the plunger looks up. If you press on it with your finger, it will not move. When everything is so, the parts are returned to their place and assemble the engine.
With the help of such a simple procedure, it is possible to restore operability to hydraulic lifters. Even an expensive additive-washing of Liqui Moly hydraulic compensators will come out no more expensive than replacing these elements with new ones.
How to flush lifters without removing them
Those who are too lazy to remove the HA can flush without dismantling. So, for this, the intake manifold is dismantled. Then take any liquid for sizing and pour it into each of the cylinders. Next, the motor is twisted by a starter. Then the cover is removed and the compensators are doused with a tool for cleaning carburetors. It is better to choose a good and expensive liquid. Then leave the car intact for a couple of hours.
Further, everything is going in the reverse order. At the time of starting the engine, it is recommended to press the gas to the floor. Smoke will come out of the exhaust pipe and various debris will fly out. Gain high speed and hold until the moment when the smoke from the exhaust pipe does not stop coming out. It is recommended to ride at high speeds for a while. Such flushing of hydraulic lifters without disassembly is very widely used by car owners. However, it is not as effective as with removal.
Additives and liquids for washing HA
According to most experienced car enthusiasts, only A92 gasoline should be used as the best flushing agent. Kerosene is also suitable. Along with these folk remedies, eminent manufacturers of auto chemical goods offer branded liquids and additives. It must be said that most of these products are ineffective. But many pour them, because they well know how much it costs to replace hydraulic lifters. Much information is available on Liqui Moly's product to reduce the knock of hydraulic lifters.
The manufacturer promises that with the help of this additive it is possible to clean not only the compensators themselves on any car, but also valve openings. The additive also improves the lubricating properties of motor oils. If necessary, the fluid can also be used as a cleaning agent for the entire lubrication system.
If, for example, the Niva-Chevrolet hydraulic compensator knocks due to pollution, then this product copes well with this problem. Reviews of motorists note that you do not even need to drain the oil. It is enough to fill one bottle of this product in the filler neck. In other cases, additives will not help - this is not a cure for all diseases. But the manufacturer still recommends pouring the additive at each oil change.
After washing, the same Niva-Chevrolet hydraulic compensator stops knocking after 50 kilometers of the car’s run. If you consider how much the new element costs, then the price of washing in 400 rubles is a significant savings. But the reviews say that this is not always effective. In advanced cases, you have to change the hydraulic expansion joints as a whole.