The engine lubrication system is combined: the most loaded parts are lubricated under pressure, and the rest are lubricated either by directional splashing, or by splashing oil flowing out of the gaps between mating parts
The pressure in the lubrication system is generated by an oil pump installed in the front cover of the cylinder block and driven from the front end of the crankshaft.
The oil enters the lubrication system through the intake pipe, through which it enters the gerotor type oil pump.
After the pump, pressurized oil is supplied to a pressure control valve installed in the oil cooler cover.
Pressure regulating valve
The pressure regulating valve is designed to keep the lubricating oil pressure within 320 kPa.
If the oil pressure after the pump becomes more than 320 kPa, the valve opens, allowing oil to flow into the discharge channel, through which it returns to the oil pan.
Taking into account the technological tolerances for the manufacture of parts and oil lines, the pressure of the lubricating oil in various engines can vary up to 69 kPa.
Further, the oil flow, passing through the oil cooler, enters the bypass valve, which opens if the pressure drop across the filter exceeds 345 kPa.
The valve opening pressure can vary within ± 34 kPa.
After the oil cooler, the oil passes through a full-flow oil filter.
The oil that has passed the full-flow filter is directed to the main oil line of the cylinder block and to the turbocharger.
The turbocharger is the first block to receive filtered, cooled oil by piping under pressure from the front timing gear cover.
A drain pipe, connected to the bottom of the turbocharger housing, returns oil to the oil pan through a channel in the cylinder block.
Lubricant for parts under load
Main oil line
In addition, the lubricating oil from the oil filter enters the main oil line through a channel at the front of the cylinder block, behind the front timing gear cover.
In addition, pressurized oil from the main oil line is supplied to lubricate the main bearings, valve train and accessory drive.
In addition, oil under pressure from the main oil line goes to other components and parts of the power train (connecting rods, pistons and camshaft).
Oil from the main oil line is supplied to the main bearings, crankshaft, piston cooling nozzles and idler gear.
The crankshaft then supplies oil to the connecting rods.
Valve train lubrication is provided through separate channels drilled in the cylinder block.
The oil flows through the holes and the slot in the cylinder head gasket.
Valve Train Lubrication
The channels drilled in the cylinder block continue in its head, going up to the holes in the rocker arm bearings and the camshaft journals.
Through the channel in the support, oil flows to the rocker arm axis, its roller and crosshead cushion.
Through a channel in the cylinder block, oil is supplied to the drive of the vacuum pump, as well as to the camshaft chain tensioner.
Rear timing gear lubrication
The rear camshaft gears and the camshaft chain drive are lubricated by a jet of oil from a hole in the cylinder head.
The oil is then drained back into the oil pan through the flywheel housing.
An SAE 15W40 heavy duty oil is recommended.
Low viscosity oils such as 10W-30 can be used at low temperatures, which can provide the required oil supply at temperatures below -5˚.
But the constant use of low viscosity oils will shorten the life of the engine.
The engine uses a gerotor type oil pump located in the front camshaft cover, driven directly by the crankshaft.
A full-flow oil cooler is used to cool the oil, Figure 6, which is located in the cover of the front timing gears.
The oil passes through the oil cooler plates, where it is cooled by the engine coolant circulating behind the plates.
The oil is filtered using a full-flow oil filter located on the intake manifold side at the front of the engine.
It is recommended to fill the filter with oil before installing it when replacing it to avoid delayed pressure build-up.
The oil pressure regulator is used to avoid high oil pressure values.
The pressure regulator, figure 7, is located in the front timing gear cover, on the exhaust manifold side.
The oil bypass valve, Figure 8, is mounted in the front timing gear cover, behind the oil cooler.
The bypass valve opens when the pressure drop across the oil filter becomes too large.
As a result, unfiltered oil continues to flow into the engine lubrication system.
The oil intake pipe (arrow in Fig. 9) is integrated into the oil pan. It is made of molded plastic and friction welded to the oil pan.
The oil-immersed part of the tube is perforated to prevent large foreign particles from entering the lubrication system.
The oil pan on some engine models allows the installation of additional heaters to facilitate engine operation at low temperatures.
When diagnosing lubrication system failures, all obvious factors related to oil pressure should be checked.
In the instrument cluster of the car there is a warning light for emergency oil pressure in the engine.
If, with the engine running, the oil pressure drop warning light comes on and remains on at increased speed, stop the engine immediately and find out the cause.
Checking the lubrication system
We open the hood and wait two or three minutes for the oil to flow into the crankcase and then check the oil level.
You need to look under the front of the car to see if the engine oil sump is punctured, if there is an oil leak.
We pay attention to the oil filter. Oil can leak from under the rubber gasket on the cover if it is damaged, or from the filter itself if the filter is loose.
We take out the oil level dipstick
This is the location of the dipstick
We wipe it with a cleaning cloth and put it in place.
Remove the dipstick again
The oil film level should be within the grooved area on the dipstick.
If the level is lower, then add oil to the norm.
We start the engine.
If at normal level the warning light goes out, you can continue driving.
If the lamp is still on, check the serviceability of the oil pressure sensor.
To do this, unscrew the oil pressure sensor, and install a mechanical pressure gauge in its place.
If the pressure at the minimum idle speed is more than 25 kPa (0.25 kgf / cm 2) and increases with increasing speed, the sensor or its electrical circuit is faulty.
A thin film of black oil on the dipstick indicates the presence of fuel.
Cloudy, colorless oil is a sign of coolant in the oil.
Possible reasons for the appearance of coolant in the oil:
- - leaks through expansion plugs;
- - violation of the tightness of the oil cooler element;
- - damage to the cylinder head or gasket;
- - cracks in the cylinder block;
- - pores in cast parts.
A leak in the oil cooler causes the oil to mix with the coolant.
After engine shutdown, residual pressure in the cooling system can cause coolant to enter the oil.
To check the tightness of the lubrication system, you need to create a pressure in it of 140 kPa.
Then remove the following parts and check for leaks:
- - rocker arm cover (the presence of leaks is a sign of cracks in the cylinder head);
- - drain plug of the engine oil pan (leaks indicate damage to the oil cooler, head gaskets, cracks in the head or cylinder block);
- - leaks through expansion plugs.
Coolant in the oil can be caused by a damaged cylinder head gasket or cracks in the cylinder head or cylinder block.
Coolant entering the oil can be caused by damage to the oil cooler gasket or the front timing gear cover gasket.
There can be only five reasons for fuel oil dilution:
- - Leakage through the high pressure pump shaft seal;
- - fuel leakage through the piston rings;
- - booster pump;
- - a crack in the cylinder head at the junction of the fuel filter and the intake manifold;
- - leaks from injectors.
We apply logic when determining the source of fuel entering the oil:
- Wear or damage to the high pressure fuel pump shaft seal will cause fuel to enter the timing gear case and then into the engine sump.
The seal design provides a tighter seal as the pressure in the pump housing increases.
The pressure presses the edge 1 more against the shaft.
Seal wear will cause seal leakage when starting and stopping the engine when case pressure is low. This malfunction is difficult to determine by pressing the pump.
Incomplete combustion in the cylinders can cause unburned fuel to drain into the sump.
This could be due to fuel leakage from the injector or compression loss due to poor piston ring performance.
An increase in white smoke when the engine is first started indicates a leak in the injector.
Fuel leakage from the injector will also result in uneven engine operation and loss of power. The injector needs to be removed, repaired or replaced.
Oil system malfunctions and remedies
- - Reason
Increased oil consumption:
- - Check the oil consumption rate
Compare the amount of oil added with the mileage of the car
- - External oil leaks
Check engine for external oil leaks, locate leaks, repair if necessary
- - Clogged crankcase ventilation system
Check and clean the crankcase breather and vent pipe
- - Oil mismatch with technical requirements
Change oil and filter
- - Increased interval between oil drain operations
Make sure oil change intervals are correct
- - Violation of the tightness of the oil cooler
Check for coolant leaks in the oil cooler
- - The oil level is above normal
Check the oil level.
Check the dipstick calibration and sump capacity. Add oil to the required level
- - The angle of inclination of the engine during operation is above normal
Refer to Engine Specifications - Engine Tilt Angle Requirements
- - Leakage of the turbocharger oil seal
Check compressor and turbocharger turbine seals
- - Incorrect seating of the piston rings (after an overhaul of the engine or installation of pistons)
Check the pressure of the crankcase gases.
In case of increased pressure of crankcase gases, check the correct seating of the piston rings.
- - Increased valve stem clearance or damaged valve stem seals
Check valve stems and seals.
- - Increased wear of the valve guides in the cylinder head
Check valve guides for wear.
Replace the cylinder head if necessary
- - Damage or wear of the piston or piston rings
Check the tightness of the intake system.
Check pistons and piston rings for damage or wear.
- - Internal engine damage
Analyze the oil composition and check the filters to determine the location of possible damage.
- - Determine what the oil is contaminated with
Analyze the oil composition to identify contaminants