2.9 Lubricating System JL4G18-D

2.9.1 Specifications
2.9.1.1 Fastener Tightening Specifications

Applications

Model

Specifications

Metric (Nm)

US English (lb-ft)

Oil Pan and Cylinder Block
Connecting Bolts

M6

8-10

6-7.4

Oil Filters and Cylinder Block
Connecting Bolts

M6

8-10

6-7.4

Oil Sensor Plug and Cylinder
Block Connecting Bolts

R1 / 8

11.5-19.5

8.6-14.4

Oil Filter and The Cylinder Pipe
Fittings

UNF3 / 4 "-16

16-24

11.8-17.8

Oil Filter Fittings

M28 × 1.5

33-37

24.4-27.4

Oil Pump Retaining Bolt

M6

8-10

6-7.4

Oil Pan Drain Plug

M12

25-35

18.5-25.9

2.9.1.2 Oil Pump Specifications

Side Clearance

0.025-0.062 mm (0.0010-0.0024 in)

Tooth Clearance

0.030-0.099 mm (0.0012-0.0039 in)

Engine Oil Pressure Sensor Plug Pressure

≤40 kPa (≤6 psi)

Oil Pump Output Pressure

0.6 MPa (87 psi)

Oil Pump Relief Valve Opening Pressure

0.42-0.58 MPa (61-85 psi)

Engine

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2.9.2 Description and Operation
2.9.2.1 Description and Operation

Oil Pan

The oil pan is installed at the bottom of the engine crankcase.
The engine oil pump draws engine oil from the oil pan. After
filtered by the oil filter, the engine oil passes through two oil
paths,  lubricating  cylinder  block  and  cylinder  head  cover
respectively. In an oil path, the engine oil passes through the
crankshaft oil passage to the connecting rod, and then to the
piston and cylinder, finally, return to the oil pan. In the other oil
path, the engine oil passes through the engine oil passage to
the  camshaft,  through  the  oil  path  within  the  camshaft,
lubricating valve assembly, then finally return to the oil pan.

Oil Pump

Oil pump draws the engine oil from the oil pan and then pump
the engine oil with pressure to the various parts of the engine.
Oil pump inlet has an oil filter - set filter. Set filter blockage may
damage the oil pump and cause the pump oil inoperative, and
the lubricating system will be unable to establish a normal oil
pressure, which will cause the engine mechanical damage.

Oil pump is driven by the crankshaft concave. As long as the
crankshaft rotates, the oil pump will be working. The oil pump
displacement is fixed, so when the engine speed is high, the
oil pump output pressure will exceed the needs of the engine
lubrication  system.  There  is  a  safety  valve  in  the  oil  pump
assembly. The safety pressure relief valve cavity is connected
with the oil pump intake chamber. When the output pressure
exceeds  0.5  MPa  (73  psi),  the  security  valve  is  open,  the
excess oil returns to the oil pump through the valve. With the
normal oil supply, the safety valve bypass is closed.

Lubrication Descriptions

The  oil  filter  seat  is  integrated  on  the  crankcase.  Engine  oil
passes through the oil filter seat bottom oil path to the oil filter.
After being filtered, engine oil passes through the oil filter seat
upper oil path to return to the cylinder block.

Engine  oil  passes  through  the  oil  path  to  the  cylinder  block
front. These oil paths will supply engine oil to the cylinder head,
main  bearing  oil  path,  VVT  solenoid  valves  and  camshaft
position actuators.

Each  cylinder  head  oil  path  introduces  engine  oil  into  the
cylinder head cover and camshaft bearing journal. Engine oil
passes through the main oil path to the VVT solenoid valve,
VVT  solenoid  valve  oil  cavity,  to  the  VVT  actuator.  VVT
solenoid valve is used to control the intake camshaft position

actuator.  Engine  Control  Module  (ECM)  controls  the  VVT
solenoid  valve.  When  the  engine  control  module  provides
power to the VVT solenoid valve, the solenoid valve guides the
engine  oil  to  flow  through  the  cylinder  head  cover  camshaft
front  bearing  caps.  Engine  oil  passes  through  the  intake
camshaft bearing caps into the camshaft journal drilled hole
and  flows  to  the  intake  camshaft  front  installation  surface.
Then,  the  engine  oil  flows  to  the  camshaft  position  actuator
corresponding oil path. VVT solenoid valve guides engine oil
into the system corresponding oil path, so that the engine oil
pressure  acting  on  the  intake  camshaft  position  actuator
internal blades. The intake camshaft (installed on the camshaft
position  actuator  inner  rotor)  rotates  relative  to  the  sprocket
(mounted on the intake camshaft position actuator housing). At
idle, the internal pin will lock the rotor to the intake camshaft
actuator housing. When starting, the cam actuator position will
maintain  the  original  position  or  the  default  position.  VVT
solenoid valve guides engine oil hydraulic pressure to loose the
lock pin, so that the intake camshaft position actuator works.

Oil pump contains a small engine oil nozzle, which sprays the
engine oil to timing chain components.

Engine oil passes through the camshaft timing chain drive belt
area or cylinder head cover and cylinder block casting oil return
path and returns to the oil pan.

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2.9.3 System Working Principle
2.9.3.1 Lubrication Schematic

1

2

3

4

5

6

7

8

9

FE02-2042b

Legend

1. Intake Camshaft
2. Exhaust Camshaft
3. Oil Filter
4. Oil Pressure Sensor Plug
5. Main Oil-Channel
6. Oil Pump

7. Oil Collection Filters
8. Oil Pan
9. VVT Actuator
10. VVT Solenoid Valve

Engine

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2.9.3.2  Engine  Oil  Pressure  Sensor  Plug
Control Principle

Engine oil pressure sensor plug is a pressure switch and is set
on  the  oil  filter.  When  the  engine  oil  pressure  is  below  the
specified value, this switch is switched off and the engine oil
pressure warning lamp will be on. When the car starts normally,
the oil pump transfers the oil pressure to the system, so this
switch is switched off and the engine oil pressure warning lamp
will be off.

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