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MODEL FOR RICH(Y40F) SERVICE MANUAL

SERVICE MANUAL RCHRM2A21 - eng.saipayadak.orgeng.saipayadak.org/CarDocument/RM/EM-Engine Mechanical-RCHRM… · 5.Typical structure and its advantages of ZG24-type gasoline

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Page 1: SERVICE MANUAL RCHRM2A21 - eng.saipayadak.orgeng.saipayadak.org/CarDocument/RM/EM-Engine Mechanical-RCHRM… · 5.Typical structure and its advantages of ZG24-type gasoline

MODEL FOR RICH(Y40F)

SERVICE MANUAL

Usr820613
Typewritten Text
RCHRM2A21
Page 2: SERVICE MANUAL RCHRM2A21 - eng.saipayadak.orgeng.saipayadak.org/CarDocument/RM/EM-Engine Mechanical-RCHRM… · 5.Typical structure and its advantages of ZG24-type gasoline

QUICK REFERENCE INDEX

GENERAL INFORMATION

MAINTENANCE

ENGINE MECHANICAL ENGINE LUBRICATION & COOLING SYSTEM

ENGINE CONTROL SYSTEM ACCELERATOR CONTROL ,FUEL& EXHAUST SYSTEMS

GI MA EM LC EC FE

Y40F

Engine for ZG24

CLUTCH MANUAL TRANSMISSION TRANSFER PROPELLER SHAFT & DIFFERENTIAL CARRIER FRONT AXLE & FRONT SUSPENSION

REAR AXLE & REAR SUSPENSION BRAKE SYSTEM STEERING SYSTEM RESTRAINT SYSTEM BODY AND DECORATION HEATER& AIR CONDITIONING ELECTRICAL SYSTEM

CL MT TF PD FA RA BR ST RS BT HA EL

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ZG24

Engine machnical

SECTION

EM Contents

1.ZG24Engine Outline

2.ZG24 Engine characteristics curve

3.Technical parameters of ZG24-type gasoline engine

4.Advanced performance overview of ZG24-type gasoline

engine

5.Typical structure and its advantages of ZG24-type gasoline

engine

6.16-valve mechanism (4-valve mechanism of each cylinder).

7.The structure of double overhead camshaft

8.Major advantages:

9.Gapless gear drive (between double overhead camshaft)13

10.Disassembly and assembly key points of ZG24-type gasoline

11.engine main parts

EM-1

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ZG24

1. ZG24Engine Outline

EM-2

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ZG24

EM-3

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ZG24

EM-4

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ZG24

EM-5

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ZG24

EM-6

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Effective torque

ti

Correction effective

Fuel consumption

Rt

Fuel consumption

ZG24

2. ZG24 Engine characteristics curve

ZG24 Total power curve

Fuel consumption

Engine Speed(r/min)

EM-7

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Model of engine 4RB2

Cylinder Qty( mm) 4

Cylinder

diameter×stroke

( mm)

95×86

Total displacement(L) 2.438

Idling speed(r/min) 750±50

Total power/rotation

speed(kW/ r/min) 102/4600~5000

Maximum

torque/rotation speed

(Nm/ r/min)

217/2600~3200

Fuel supply method Closed-loop control and multi-point

sequential injection

Pollutant emission

limit value

Meet 1999/102/EC EuroⅢ Emission

Limit

Fuel brand #93 or #95 quality unleaded gasoline

(GB17930)

Engine oil brand SG-class 10W-30 or

15W-40

Compression ratio 9.2

External dimensions

( mm) 760×552×670

EM-8

ZG24

3. Technical parameters of ZG24-type gasoline engine

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ZG24

4. Advanced performance overview of ZG24-type gasoline engine

4.1 Advancement of electric control system

Electric control system (MT20U2 system for short) of ZG24-type

gasoline engine is the system with Delphi MT20U2 engine control module

(ECM) at the core. Viewing from its functions, it has been able to meet

relevant technical requirements of Euro Ⅲ and Ⅳ Emission Regulations.

Meanwhile, it also reserves relevant functions of European On-Board

Diagnostic (EOBD).

4.2 Possessing well dynamic performance

This engine has characteristics of high power(102Kw)and high torque

(217N.m). Torque characteristic curve is smooth and the engine has well

easement and acceleration capacity.

4.3 Excellent emission performance

Because advanced combustion system, ignition control technology,

modern electric control fuel injection technology and ternary catalytic

instruments are adopted to carry out off-engine purification, emission index

of this engine meets requirements of Euro Ⅲ Regulation in one go. (It has

respectively passed relevant emission detections: 9-mode test cycle

experimental emission detection, 15-mode test cycle emission detection,

crankcase ventilation emission detection and double idle emission detection,

etc).

4.4 Compact conformation, small volume and light weight

EM-9

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ZG24

In overall

arrangement:

ZG24-type

gasoline

engine

adopts

chain-driving double overhead camshaft (without bearing), portal cylinder

body without cover, ultrashort cylinder center distance (102.5)and short

connecting rod (hole distance 135), water channel and oil duct with

optimum design, which reduce integrated dimensions of the engine; on

aspect of accessories: oil pump and water pump attaching on sprocket room,

starter lightweighting, spin-on filter and reinforced polypropylene fan, etc.

make accessories system have light weight and small volume; on aspect of

material selecting: aluminous cylinder cap and sprocket room, etc are

adopted, which further reduces weight of the complete machine (total mass

is 165kg and specific mass is 1.62kg/kw).

4.5 Excellent fuel economy

ZG24 adopts advanced combustion chamber mechanism, high

compression ratio and multi-point electric control fuel sequential injection,

strict matching calibration, which make its combustion more sufficiently.

Therefore, it possesses very high thermal efficiency and broad economic

zone; long-channel air inlet pipe is adopted to improve charging efficiency;

lightweighting piston linkage mechanism, typical convex skirt piston,

silicone oil clutch fan and other structures are adopted to improve

mechanical efficiency.

Inlet/exhaust valve forms a certain inclination with the plumb

direction, in this way the spark plug can be put near the center of

EM-10

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ZG24

combustion chamber, which is in favor of cyclic flame spreading and

improving fuel economy, especially fuel economy under partial load.

4.6 Low vibration and noise

Because ZG24 adopts advanced structure and combustion process,

strict ignition timing calibration and optimum adjusting in knocking zone,

which reduce mechanical movement noise and combustion breakout noise;

double-layer valve chamber cover cap structure reduces noise transmission

in valve chamber; for engine block and cylinder cap design, its external

surface adopts structure and measures reducing internal exciting force

response, which further reduces noise.

Crankshaft-piston-connecting rod gear with lightweighting design and

belt pulley and silicone oil clutch fan with rubber vibration isolator make

this engine have small vibration and low noise. Camshaft directly running in

aluminous cap is in favor of reducing noise.

4.7 Convenient maintenance

Design and arrangement is brief and compact; integration degree of

ignition and electric control system is high and clear; overhaul of all parts is

convenient; the chain automatically keeps constant pressure and tightening,

etc, which greatly simplify and facilitate maintenance work.

5. Typical structure and its advantages of ZG24-type gasoline engine

5.1 16-valve mechanism (4-valve mechanism of each cylinder)

EM-11

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ZG24

Modern vehicle has a higher and higher performance requirement on

vehicle power---engine: increase power per liter, improve dynamic and

sensibility of the engine under different operating conditions and meanwhile,

improve fuel consumption and reduce exhausting pollution, therefore,

4-valve mechanism receives more and more attention, its advantages are:

(1) Air inlet flow area increases, flow resistance reduces, therefore,

coefficient of charge increases, pump gas loss reduces and torque per liter

and power per liter of the engine increases.

(2)Inlet channel design freedom is large, shape of combustion chamber

is near hemispheric, spark plug can be put in position near the center, which

is in favor of organizing gas mixture in cylinder to form tumble and swirl

and realize fast burning. It can properly improve compression ratio and

reduce oil consumption and HC compositions emission.

(3) Moving parts of valve train have small mass, small inertia force and

strong structural rigidity, which is in

favor of improving engine speed

and reducing engine noise.

5.2 The

structure

of

double

overhead camshaft

EM-12

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ZG24

Major advantages: (1)Valve mechanism is directly driven by double

overhead camshaft(DOHC) and there is no push rod or rocking arm, which

reduces inertia mass, i.e. reduces inertia force of valve mechanism and

consequently reduces vibrating trend of valve and deformation amount of

valve mechanism.

(2) It can reduce valve clearance and reduce noise to the maximum

extend.

(3) Improve follow-up characteristic of valve to camshaft and increase

engine speed.

(4) Small inertia mass of the structure enables valve to open and close

rapidly, prolong full opening time of valve, improve ventilation operating

condition of cylinder, increase volume efficiency of combustion chamber

and consequently greatly increase engine performance.

5.3 Gapless gear drive (between double overhead camshaft)

Driving disadvantages of traditional gear: tooth flank is liable to be

worn. After wearing, timing accuracy of engine reduces. In order to prevent

gear

thermal

EM-13

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ZG24

expansion clocking, enough clearance must be left between two driving

gears, therefore very big noise will be generated when running.

ZG24 adopts the structure of gapless gear drive: the structure consists

of master gear and pinion. There is a torsion spring clamped between master

gear and pinion. Two ends of the torsion spring prop up two pins

respectively fixed on master gear and pinion. The torsion spring make tooth

flanks of master gear and pinion form a small angle. The form look like

scissors.

With this structure, when temperature reducing, clearance between

driving gear and driven gear of double overhead camshaft is comparatively

bigger, at this point, under the elastic force of torsion spring, the two tooth

flanks of master gear and pinion of gapless gear form a small angle to fill up

the clearance between driving gear and driven gear. Vice versa.

Advantages of this structure: increase timing accuracy; reduce engine

noise.

6. Disassembly and assembly key points of ZG24-type gasoline engine

main parts

6.1 Assembly of

cylinder cap

Cylinder cap is also

one of

the

important

EM-14

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ZG24

components of engine. It mainly integrates main components and parts

(camshaft, valve and tappet, etc.) of valve mechanism and some components

and parts (e.g. spark plug, etc.) of ignition system, by which normal air inlet,

exhaust, ignition, combustion, apply work etc. can be completed.

Cylinder cap of ZG24-type gasoline engine is forged with aluminum

alloy. It has cross-flow inlet & exhaust channel, awning combustion

chamber; its spark plug lies in the center of combustion chamber; inlet and

exhaust respectively has 5

camshaft fulcrum bearings

and fulcrum bearing caps; oil

injector is

installed

on

cylinder cap. Adopt thin-wall

cast aluminum alloys valve

chamber cover with the structure of vibration reduction and sound

deadening.

Dismantling key points of cylinder cap parts

Put piston of the first

cylinder on the position of top

dead center.

Rotate crankshaft pulley to

EM-15

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ZG24

make timing mark of the pulley align at the mark of “0” on cap of sprocket

room. As shown in drawing.

Dismantle high voltage line, spark plug, cylinder cap, ignition coil,

inlet manifold support strip, oil pipe and uncoupling cooling water bypass

hose, etc.

Dismantle timing sprocket of admission camshaft.

Make assembly mark on sprocket and chains, as shown in drawing.

Dismantle bolt of

admission camshaft sprocket,

chain tightener assembly and

washer, dismantle timing

sprocket of admission cam shaft, camshaft bearing cap and camshaft from

admission cam shaft.

Unscrew camshaft bearing

cap bolt, dismantle camshaft

bearing cap and camshaft and

dismantle cylinder cap in 2~3

steps according to the drawing.

EM-16

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ZG24

Firstly screw off the 2 bolts in front of cylinder cap, as shown in

drawing.

Then according to the sequence shown in drawing, gradually screw off

10 cylinder head bolts and dismantle cylinder cap in 2~3 steps.

Inspection of cylinder cap

Inspection of worn condition of valve seat:

Inspect worn condition of valve seat and whether there is damage and

if necessary, should reseat valve seat. At this point, should firstly inspect

worn condition of valve guide, if it has been worn excessively, should firstly

replace valve guide; then thin the valve seat with valve seat reamer or valve

seat grinder. Valve seat should be machined into the shape shown in the

drawing; the width of contact segment of valve seat and valve-face is 1.0

mm~1.4 mm.

Finally, grind valve and valve seat with valve grinding compound to

make it joint closely without air leakage. After grinding, completely clean

valve seat, valve and internal hole

of valve guide.

Grinded valve should not be

replaced.

Refer to relevant technical

documents for inspection of other

parts.

EM-17

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ZG24

Assembly key points of cylinder cap parts

Valve and valve seat should be sealed reliably. After assembling spark

plug, fill the combustion chamber with coal oil and observe that there is no

obvious leakage within 1min.

When assembling valve oil seal, should not damage or scuff the lip;

when assembling the locker, should not scuff valve stem. When assembling

tappet and washer, ensure inlet valve clearance to be 0.15 mm~0.25 mm

and exhaust valve clearance to be 0.25 mm~0.35 mm.

1) Assembly of cylinder cap

Assemble cylinder cap on engine block and fix it with pin bush. Apply

sealant at the joint part

of sprocket room and

engine block and

assemble cylinder

cushion and cylinder

cap (as shown in

drawing).

Apply small amount of engine oil to screw thread of cylinder head

bolts and screw down the 10 bolts as per sequence shown in the drawing.

EM-18

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ZG24

Screw down force of the first time is 39N.m ± 4 N.m, screw down of the

second time is 90°±5° and the third time 90°±5°.

2) Assembly of camshaft

When assembling camshaft, should firstly clean joint line and apply

appropriate amount of engine oil to shaft neck surface of camshaft; then, put

camshaft and camshaft bearing cap. Back and forth direction of camshaft

and sequence number and forward mark of camshaft bearing cap must be

correct and knock on camshaft bearing cap slightly with rubber ha mmer to

the designated position. Then apply a small amount of engine oil to screw

thread of camshaft bearing cap bolts, screw down with fixed torque wrench

and the tightening moment is 16N.m±3 N.m.

Notice:

When assembling admission cam shaft, should make camshaft angle

position upward; when assembling exhaust cam shaft, should align timing

mark on driving gear of admission cam shaft with that on gear of exhaust

cam shaft.

3)

Assembly of timing

sprocket of admission cam

shaft

EM-19

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ZG24

Lift sprocket and chains with hand. Meanwhile, rotate the crankshaft

until piston of the first and the fourth cylinders being put on the position of

top dead center. Rotate crankshaft to align timing mark on gear of admission

cam shaft with that on gear of exhaust cam shaft and make them on the same

straight line (angle positioning pin on admission cam shaft should be

upward); align the sprocket with the angle positioning pin on admission cam

shaft and assemble it, then assemble bolt and screw down.

4)

Assembly of tightener

Loosen the pawl, completely press the gear rack in and cover the pin

hook on fixed pin to make the gear rack can not spring out; assemble

washer and tightener to the designated position together and screw down

with 2 nuts. Rotate the crankshaft to make pin hook of tightener come away

from fixed pin of gear rack, the gear rack will spring out and make the

crawler shoe bear down on chains, and consequently tighten chains.

EM-20

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Inlet valve Exhaust valve

Clearance

(cold state)

0.15 mm~0.25 mm 0.25 mm~0.35 mm

ZG24

5) Inspection and adjusting of valve clearance

Inspection of valve

clearance

Rotate crankshaft

pulley to make it on the

position of top dead

center of first cylinder

compression. Inspect

whether valve clearance

shown in top part of the

drawing is correct with

clearance gauge, otherwise should replace washer and make adjusting.

Rotate crankshaft pulley for a circle and align the groove of pulley with

timing mark “0”, Inspect whether valve clearance shown in bottom part of

the drawing is correct with clearance gauge, otherwise should replace

washer and make adjusting.

Adjusting of valve clearance

EM-21

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ZG24

Press valve tappet down with valve clearance adjusting clamp and keep

the valve tappet on the position

of downward with valve

clearance adjusting supporting

rod. Take off washer with valve

clearance adjusting plectrum,

inspect and adjust valve

clearance.

6.2 Timing sprocket mechanism

Dismantling key points of timing sprocket mechanism

After dismantling cylinder cap, dismantle followings accords to

sequence: fan belt, silicone oil clutch (fan), water pump pulley, AC

generator, crankshaft pulley, oil pan, oil filter, sprocket room, cam shaft

timing sprocket,

admission cam shaft

timing sprocket, crawler

shoe subassembly,

vibration damper plate

subassembly, crankshaft

timing sprocket.

Inspection of timing sprocket mechanism

EM-22

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ZG24

Straighten the chain, and choose 3 to 4 positions to measure the total

length of chain of 16 sections, whose length should be 142.875 mm. And if

the value is higher, the chain should be replaced.

Inspection of

sprocket is conducted as

the drawing. The

minimum value of

admission cam shaft

timing sprocket is 113.8

mm.

Inspection of

subassembly of crawler shoe and vibration damper plate focuses on whether

the maximum abrasion loss is 1mm.

Assembly of timing sprocket mechanism

Rotate crankshaft to make keyway upward, and install woodruff key

and crankshaft timing sprocket.

Install subassembly of crawler shoe and vibration damping

subassembly.

Assemble cam shaft timing chain and admission cam shaft timing

sprocket.

EM-23

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ZG24

When crankshaft timing sprocket is installed to crankshaft timing

sprocket, align black chain-timing mark of chain with timing rut mark of

cam shaft timing sprocket.

Align timing mark of admission cam shaft timing sprocket with

corresponding timing mark of cam shaft timing chain.

Make sure that subassembly of crawler shoe and vibration damper plate

are assembled in right place.

Wrap chains, subassembly of crawler shoe and vibration damper plate

together with soft cord to avoid loose.

Assemble sprocket room, oil filter, oil pan, crankshaft pulley, AC

generator, water pump pulley, silicone oil clutch (fan), fan belt and cylinder

cap in sequence.

6.3 Assembly of cylinder body

Cylinder body,

where

many

essential

components

(crankshaft,

of oil

engine pump,

and

piston

etc.)

are

assembled,

is

an

important frame of engine.

EM-24

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ZG24

The indispensable working surroundings of engine are composed of cylinder

and cap. Engine can apply work outwards due to combustion chamber

composed of cylinder body and cap. And water jacket ensures engine

working under a normal temperature. Oil duct gives excellent lubricating

conditions to each component. A complete closed loop is formed through

assembling each component.

Cylinder body of ZG24-type gasoline engine adopts portal, i.e. bottom

plane of cylinder body is lower than assembly plane of crankshaft, which

obviously improves flexural stiffness of longitudinal plane and torsional

rigidity of encircling axis of crankshaft and is good for consolidation and

improvement of engine. Meanwhile, bottom plane of cylinder body forms an

integrated plane matching with oil pan making sealing easily.

Because of adopting dry liner, which combines cylinder and cylinder

body into integrity, structure is simple and compact, and rigidity

overwhelms wet liner. Cylinder body adopts fully supporting type, making

distribution of load more even.

Dismantling key points of components of cylinder body

Subassembly of piston connecting-rod

Before taking out subassembly of piston connecting-rod, shall place

rubber sheath or plastic sheath on connecting-rod bolt to prevent from

damaging crankshaft connecting-rod journal.

Collocate bearing bushes of dismantled subassembly of piston

EM-25

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Standard Value Max

Value

Measures

beyond Scopes

Axial

clearance

0.160 mm~0.312 mm 0.35

mm Connecting

rod Radial

clearance

0.032 mm~0.058 mm 0.10

mm

Replace

components

Axial

clearance

0.040 mm~0.212 mm - Replace thrust

washer

Crankshaft

Radial

clearance

0.030 mm ~ 0.057 mm

(The third main journal)

0.025 mm ~ 0.049 mm

(The other main journal)

0.10

mm Replace main

bearing bush

ZG24

connecting-rod in right order. Don’t change the order when assembling.

When dismantling main bearing cap, main bearing bush, crankshaft and

thrust washer, place them in order

for easy assembly.

Inspection of components

of cylinder body

EM-26

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ZG24

94.995 mm~95.005 mm -

If

exceeding

95.005 mm~95.015 mm

-

maximum

Diameter of

bore

95.015 mm~95.025 mm

-

diameter

or

hole

piston scraping

appears,

cylinder

bore

or

replace cylinder

Upper plane

of 0.05 mm(planeness)

-

- cylinder

94.925 mm~94.935 mm

-

Piston diameter

94.935 mm~94.945 mm 94.945 mm~94.955 mm

- -

Piston

clearance

to

cylinder 0.042 mm~0.062 mm

0.1 mm

Replace piston or bore cylinder

No.1: 0.030 mm ~ 0.70 -

mm

Ring groove clearance No.2: 0.030 mm ~ 0.70 - mm

Replace piston

Piston

ring

Joint No.1: 0.25 mm~0.40 mm

-

Replace piston clearance

Clearance

No.2: 0.40 mm~0.55 mm between 0.005 mm~0.011 mm

EM-27

- 0.015

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ZG24

piston pins and holes

Clearance between 0.005 mm~0.011 mm

0.015

piston pin and small

head

pore

of

connecting rod

Diameter of screw pile 7.8 mm~7.9 mm

of connecting rod

Radial runout of main Max 0.03 mm

axis of crankshaft

EM-28

7.6 mm -

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ZG24

Key points of assembling components of cylinder body

1) Assembly of crankshaft and main bearing bush

Choose corresponding main bearing bushes according to number of

rear main axis hole of downward plane of cylinder body, and install them in

corresponding cylinder bodies and main bearing cap.

Notice: put bearing bush with oil holes into cylinder, and apply a little

engine oil on the inner side of main bearing bush.

As in the drawing, put thrust washer in the both sides of No. 3 main

gear seat of cylinder, with oil groove outwards. As shown in drawing.

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Put crankshaft in the cylinder with main bearing bush.

As in the drawing, put lower thrust washer at the both sides of No. 3

main bearing cap of cylinder with oil groove outwards, and put main bearing

cap in the right places according to arrowhead and original sequence. As

shown in drawing.

Before assembling main bearing cap bolt, should lay a little engine oil on

screwthread parts, and screw tightly main bearing cap bolt alternately from

the middle to both ends

twice. As shown in drawing.

Tightening moment is 39

N.m.

Mark at the forepart of

the top of bolts, and rotate

90° as in the drawing to

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further tighten bolts.

Rotate crankshaft to check whether it is flexible and whether there is

jamming phenomenon, and examine axial clearance of crankshaft.

2)

Assembly of piston connecting rod mechanism

According to the size of connecting

rod big-end hole, categorize and choose

corresponding connecting rod bearing

bush, put it into big-end and hole of

connecting rod cap, bearing bush with oil

holes into big-end of connecting rod.

Cover connecting rod bolt with

flexible tube, and apply a small amount of engine oil on the cylinder wall

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and journal of crankshaft connecting-rod.

Install piston connecting rod mechanism into taper sleeve to make

depression mark of piston align at the frontage of cylinder, and slightly push

subassembly of piston connecting rod into cylinder.

As in the drawing, assemble connecting rod cap to ensure the right

direction of onward mark of connecting rod cap, and connecting rod cap and

the original connecting rod are matched.

Tighten connecting rod nut in two steps, with tightening moment of

29N.m. Mark at the foreside of nut end, and then rotate 90° to further tighten

each nut.

Crankshaft should be flexible to rotate without ja mming phenomenon.

Axial and radial clearance of connecting rod should conform to

requirements.

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6.4 Cooling system

Cylinder body of ZG24-type gasoline engine adopts forced water

cooling circulation with a thermostat fixed at water entrance. As shown in

drawing.

Keep adequate coolant in the water tank. If using antifreeze, please mix

according to instructions of antifreeze. Due to thermostat at water entrance,

for the first time, add or replace coolant fully. Add more after generator

running until water level is stable.

Examine quality of coolant whether it is clean, oil stain. Change if

necessary.

Examine sealing condition of coolant system.

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Examine and adjust tightness of fan belt. Press in the middle of belt

between AC generator and water pump with 98N pressure. Bending of

used belt is 7 to 8

mm, and new 5 to 7

mm.

Ensure that groove of fan belt and belt wheel is in good joint. As shown

in the drawing.

Examine thermostat.

88℃ ~

76℃

Temperature of starting

valve: 88℃~76℃

Lifting height of

valve: over 8mm at

88℃

If temperature of starting valve rises or closing state doesn’t conform to

regulations or requirements, should replace thermostat.

Examine water pump.

Examine status of water pump and timing sprocket room about crack or

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hurt of joint line, and examine whether water pump bearing rotates flexibly

and there is noise.

6.5 Lubricating system

6.6 Key points to mechanism

Lubricating mode is fully filtering combined pressure & splashing.

Lubricating oil pump is

rotor type, and internal

and external rotors

installed in sprocket room

are directly driven by

damp crankshaft pulley.

Main oil duct is installed

in cylinder body, through

oil duct, main axis, journal of connection-bearing and camshaft bearing

(there is oil line to cylinder body) are lubricated; sprocket, chains and

tightening mechanism are lubricated by oil injector in main oil duct; valve

tappet, valve, bore hole, piston pin and pinholes and so on are lubricated by

splashing.

Oil pump of gasoline engine is powder metallurgical oil pump with

internal and external rotors. Power is conveyed to crankshaft pulley by

crankshaft rotating, and then conveyed to oil pump by crankshaft pulley.

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Internal rotator of oil pump stirs external rotator to make it move eccentric

motion, which is attributed to difference of volume and pressure of working

space. Oil will be extracted from oil pan to working room of oil pump by

negative pressure produced, while positive pressure will push oil to main oil

duct. If there is fault in oil pump: 1. if foreign matters exist and oil pump is

ja mmed, camshaft and distributor block tooth will be damaged; 2. when oil

pressure is not rather little, it will cause each motive part of engine makes

dry friction and the complete machine break out.

Oil filter: engine works in a fairly clean lubricating condition. If oil is

dirty, it will cause deterioration of lubricating conditions of motive parts, or

even damage of accessories. Oil filter is a device of filtering oil, which can

filter out unclean oil.

Oil-break alarm is a pressure transducer, whose sensing source is set in

oil duct. When oil pump is working, in oil duct, there should be lubricating

with certain

pressure ensuring

every component of

engine in normal

lubricating

condition, and

which is sensed by oil alarm. In general condition, after starting engine,

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pressure of lubricating oil in duct will rise to push the slice in alarm.

Meanwhile, cut off, and if the driver sees that the indicator lamp is off, he

can judge that the lubricating condition of each components of engine is in

normal condition.

Key points of assembly

1) As shown in the drawing, when applying sealant on installation

face of bottom cover, should notice that diameter of applying

sealant is about 3.5 mm, and the sealant should be even and

continuous.

6.7 Key points of admission and exhaust system structure

Functions of inlet manifold include distributing air, fuel, oil air of

crankcase ventilation and waste air of EGR evenly to each cylinder, and

improving coefficient of charge by shape and length of inlet manifold and

voltage regulation chamber. Function of exhaust manifold is to gather the

waste air discharged from each cylinder of engine to lead it into exhaust

main.

Ensure smooth, even admission and high efficient charge by adopting

aluminum alloy and long independent air duct of each cylinder; exhaust pipe

is steel pipe and has the properties of excellent thermal stability and liability,

and optimum designed structure is good for avoiding exhaust interference of

cylinders and decreasing interference of exhaust pressure wave.

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