Various malfunctions associated with the oil pump will necessarily lead to serious violations in the operation of the engine. The main function of the oil pump is to provide pressure in the engine lubrication system. The bulk of the elements in the engine are lubricated by spraying. If the oil pump does not fulfill its function, the parts will not be lubricated. As a result, disaster and inevitable overhaul. Let's look at the main malfunctions of this unit, and also learn how to check the oil pump.
Oil pumps for ICE cars
Since different cars are equipped with different types of engines with different operating parameters, the design of oil pumps can also be different. All modifications of these devices are divided into adjustable and unregulated.
For adjustable models, it is possible to change the performance in order to achieve optimal pressure in the system under various conditions. In the case of unregulated devices, the parameters are adjusted by means of special pressure reducing valves.
In the engines of cars most often install gear and rotary type oil pumps. In this case, the movement of oil through the system and the creation of pressure is carried out thanks to the rotor blades.
In the gear type of pumps, these same functions are performed due to the movement of the gears. They can be performed in two versions - with an external type of gearing or with an internal one. A pump with external gearing has two gears located next to each other, and with an internal gear one in the other. With the same performance, the overall dimensions of gear pumps differ in the type of gearing.
Gear
The unit is arranged as follows. In its case, the leading and driven gears are installed. They provide lubricant movement through a special channel into the oil system. Depending on the speed of the crankshaft, the performance of the pump changes. If the oil pressure is higher than the permissible norm, then a part of the lubricating fluid is sent to the suction part or directly to the crankcase using a pressure reducing valve. Gear pumps are not automatically adjustable.
Rotary
The design of this type of unit is a bit more complicated. The device consists of two rotors - a slave and a master. Both are enclosed in a housing.
If the pump is unregulated, the oil that is sucked in by the device passes through the rotor blades. If the pressure level in the system is higher than the nominal or design pressure, then a pressure reducing valve is activated to relieve excess pressure.
In adjustable devices there is a special movable stator equipped with a spring. It regulates and provides constant oil pressure regardless of the number of revolutions of the engine crankshaft. The stator is designed to control constant pressure by changing the volume of the cavity between the rotors. To do this, the stator rotates in the necessary direction.
Malfunctions
Oil pumps, although simple in design, but still not eternal. Periodically, they may fail. Before you learn how to check the oil pump, you need to understand the typical faults and their causes.
So, frequent damage is gasket damage, clogged oil filters. Another malfunction is not directly related to the pump - this is the wrong fixing of the oil filter. Also, the device malfunctions due to increased wear of the main elements. Another common malfunction is a failure of the pressure reducing valve.
Symptoms
To understand how to check the oil pump, you need to be able to determine the causes of failure according to their symptoms.
One of the first signs that the pump is damaged is the oil pressure lamp on the dashboard. If it is on, urgently need to make sure that the pressure in the system is normal. If it is below normal, then check the pump. Also pay attention to the amount of grease and its consumption.
Causes of breakdowns
The oil pressure in the system drops if the fluid level in the crankcase drops. It is also possible that the pump had nothing to do with, but a device that controls the pressure failed. One of the popular reasons is poor quality oil or a product that is not suitable for a particular type of engine. Often, an oil pump fails due to normal wear and tear. It happens that the pressure reducing valve fails.
Verification Methods
In fact, there are not many ways to check the oil pump. Functional check is carried out using a manometer - this way you can verify the level of oil pressure. Then you need to dismantle the device and carry out troubleshooting, followed by repair or replacement.
Pressure gauge check
Each car owner should know how to check the pressure of the oil pump on the car - this will avoid dangerous consequences for the engine in case of malfunctions.
A pressure gauge is installed instead of the oil pressure sensor. This is the only way that can reliably verify the serviceability or malfunction of oil pumps. In this case, the pump itself can not be removed from the engine. You can purchase ready-made kits for measuring pressure in the lubrication system or make the device yourself.
Expert Advice
In order to check the operability of the oil pump, you will need a liquid manometer. These devices are in auto parts stores. Also for these purposes, you can use any industrial pressure gauge, but you should pay attention to the measuring scale - it should be adequate. Then you should stock up with an adapter, which should be screwed into the sensor hole. On its counterpart a hose fitting must be made or a thread for screwing the connecting hose. The adapter can be ordered at any turning workshop.
To make the adapter, you need to know the parameters of the mounting hole and the parameters of the thread. Then, based on these data, a sketch is compiled. Another option is to show the machinist old or broken, or maybe even a working sensor, and he will carve out the necessary part on it.
Experienced drivers know another way to check the health of the oil pump. Here you can do without a turner. They take a faulty or old oil pressure sensor, remove everything inside and make an adapter on its basis. For VAZ, you can find ready-made fittings-tees on sale.
How to measure?
How to check engine oil pump? The technology is the same for all motors. There is a slight difference only in the threshold pressure level values - it is different for different engines. The minimum allowable pressure and its level for valve operation can be found in the instructions for the car.
Using the example of VAZ classics, we will look at how to check if the oil pump is working. It should be measured in two modes - on a cold and a hot motor.
Measurements on the cold engine
In order to measure the pressure, before starting the engine, it is necessary to make sure that the oil temperature is equal to the temperature of the medium. The emergency sensor in the VAZ is configured to operate at a pressure of 0.33 kgf per square centimeter. If the measurement result turned out to be so, then the dismantling of the pump and its troubleshooting are mandatory. With a smooth increase in the number of revolutions of the crankshaft, the pressure should increase to 4.5 kgf per square centimeter. The pressure reducing valve should work, so the pressure will not increase further.
On a hot motor
When the oil temperature drops, its viscosity rises. This is good for efficient pump operation. To obtain adequate measurement results, it is best to measure the pressure on a warm engine. Since the oil is heated much more slowly than the coolant, the engine is allowed to work a little longer after reaching the operating temperature.
In the lubrication system of a serviceable motor with a serviceable pump, the pressure should be in the range of 3.5-4.5 kgf per square centimeter at 5600 crankshaft revolutions. If the measurement values differ from the nominal value, then the motor will lack lubrication in some modes.
Troubleshooting and repair of the removed element
Let's see how to check the removed oil pump. The check consists in visual inspection, measurements and comparison of the measurement result with the nominal dimensions.
Unscrew the cover of the oil receiver together with a pressure reducing valve. It is worth making an effort so that the thrust washer of the spring is not lost. Next, note that some bolts will be smaller than others. Such a bolt should then fall back into place.
A vernier caliper measures the spring. At rest, it should have at least 38 millimeters in length. Then remove the cover, on which there will be traces of the development of gears. If the seizures are deep, the wear on the oil pump is large. The cover can be repaired - its plane should be leveled.
Next, the drive gear is removed and the condition of its teeth is visually checked. If the teeth are frayed and scuffed, this indicates a lot of wear. You should also check the driven gear. The main thing in it is the hole in which the axis of fixation is located.
Then check the walls of the housing of the device and the axis of the driven gear. Potholes, grooves, various defects indicate that garbage got into the working area inside the pump.
Pressure reducing valve
There are practically no methods that allow you to check the pressure reducing valve of the oil pump without the need for dismantling. But you can check it with your mouth - even experts recommend this method. A tissue is applied to the valve fitting through which air passes well. Next, take a sharp breath. If there is strong resistance, then the valve is working.
Automatic transmission
If there is a manometer, then how to check the automatic transmission oil pump, you can not tell. The principle of verification is the same. The normal pressure level is from 2.5 to 5 bar. But you need to understand that for an automatic transmission, not only a disadvantage is harmful, but also an excess of oil pressure (or rather, ATP fluid).
Conclusion
As you can see, there are not many ways to check oil pumps, but it’s quite enough to find out if the device works or not. Do not neglect the oil system. If the pressure lamp is not lit, it is advisable to check the indicators in the system with a manometer. If the lamp is constantly on, do not delay the diagnosis. If the sensor is from a different car model and the lamp lights up periodically, this is also an occasion for checks.