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MODEL FOR RICH(Y40F)
SERVICE MANUAL
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
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
ZG24
1. ZG24Engine Outline
EM-2
ZG24
EM-3
ZG24
EM-4
ZG24
EM-5
ZG24
EM-6
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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 -
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.
EM-29
ZG24
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
EM-30
ZG24
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
EM-31
ZG24
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.
EM-32
ZG24
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.
EM-33
ZG24
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
EM-34
ZG24
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.
EM-35
ZG24
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,
EM-36
ZG24
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.
EM-37
ZG24
EM-38