Achievable functions of WD615 engine
For testing WD615 engine,
test whether the oil pressure, water temperature,
intake pressure, rotational speed and battery
voltage are normal, and whether the engine is
running normally, so as to determine whether
the engine has fault or not, possible fault and
Main technical parameters：
Length *width *height of test bench：
Oil pressure gauge value: 0-1.0Mpa
Water thermometer value: 0-120°C
Manifold pressure gauge value: 0-0.1Mpa
Tachometer value: 0-3,000rpm
Battery voltage value: 0-32V
Engine before trial-manufacture operation process
Lift the engine with a gantry hanger and connect
the front and rear support plate bolts to the engine.
Lift the engine into place and connect
the engine to the test bench suspended
brace with the front and rear support plates.
By adjusting the screw height of the
suspended brace, the engine is adjusted in place.
To align the center of the engine fan to the center
height of water tank and intercooling.
Engine fan to the test bench front-end
intercooled fixed mount 40mm.
Front support connecting bolt: 8 M12*30
hexagon bolts with flat gasket connection;
4只M14*1.5*50 外六角螺栓 配平墊和彈墊
Front support connecting bolt: 2 M14*1.5*30
hexagon bolts with flat gasket and spring washer.
The inlet and outlet interface of the water tank
and the inlet and outlet interface of the intercooler
are connected to the engine respectively through
the silicone tube, and the clamp is used to fix firmly.
After filling the antifreeze, the pipeline
connection is checked to ensure that the engine
can run normally after ignition without leakage.
Connecting warm air joint:
Inside diameter of high-pressure pipe φ22mm.
Connecting expansion kettle: two φ8mm
one is connected to the small circulating joint
of the water tank,
the other is connected to the warm air joint;
a high pressure pipe φ22mm is connected
to the outlet connection pipe of the water tank,
which is mainly used for filling the antifreeze;
the clamp is used to fix firmly.
After filling the antifreeze,
the pipeline connection is checked to ensure
that the engine can run normally
after ignition without leakage.
Connect the engine air filter to the air filter
assembly of the test bench.
Connect the exhaust end of the turbocharged
port to the exhaust pipe of the test bench
and fix firmly with a clamp.
Connect hand-held throttle bracket
and flameout cylinder.
Connect diesel pipeline, inlet and return pipe.
Connect battery cable to the battery switch
Connect other pipeline harness,
such as sensors for detection,
and hold it firmly in position.
Connect the hand-held throttle stay of
control panel to the bracket and flameout cylinder;
Finally, check the pipeline connection to ensure
that the connection is reliable and correct.
Operation process of engine performance verification
Turn on the ignition key switch,
the battery voltage meter displays 24V.
By controlling the hand-held throttle,
the different rotational speeds
of the engine can be realized.
Read the meter value on the control panel,
respectively, and compare with the reference value
on the vehicle: Test engine operation, readable
numerical oil pressure, water temperature, intake
pressure, engine rotational speed and battery
Rotational speed 600rpm:
Oil pressure 0.5mpa [idle speed]
Rotational speed 1,000rpm:
Oil pressure 0.6mpa
Rotational speed 1,500rpm,
oil pressure 0.6mpa,
intake pressure 0.01mpa
Rotational speed 2,000rpm,
oil pressure 0.65mpa,
intake pressure 0.02mpa
After the engine has been running for 30 minutes,
the water thermometer shows about 50 ℃
Release the hand-held throttle,
turn off the ignition key,
stop the engine from running,
lift the engine down,
and finish the engine test.
Principle fault list
Determine whether the tested engine is running
properly or not through the size of the meter
value on the control panel after ignition.
Reason of rough idling
The first reason is the leakage of the intake system,
intake pipe and various valves.
Air enters from the intake pipe and exhaust gas
entering into the intake pipe will cause the mixer
to be too dense and too thin, causing the engine
to burn abnormally. There is excessive fouling on
the throttle and air inlet. Misalignment of
idle air inflow.
If the large pump has dripping or
blocking phenomenon, it cannot filter the oil,
resulting in the mixture is too dense or too thin,
which makes individual cylinders work poorly and
leads to unstable engine idle speed.
Fuel pressure fault. When the oil pressure is too
low, the mixture becomes too thin due to the
decrease of fuel-injection quantity; When the oil
pressure is too high, the actual fuel-injection
quantity increases, which causes too thick mixture.
Misalignment of fuel-injection quantity.
The first is the valve actuating mechanism,
the failure of valve actuating mechanism
causes the power of individual cylinders to
decrease too much and the power is unbalanced.
The second is valve face and valve retainer
have too much carbon deposit, causing valve seal
is not firm. The third is the actuator and
piston-connecting rod mechanism,
which may cause the compression
pressure to be inconsistent with faults.
Exhaust system blocking
When the three-way catalyst causes local or
random blocking due to gumming, carbon
deposition and fragmentation, it will increase
the back pressure of exhaust gas, make the intake
pipe vacuum too low, and cause the engine exhaust
gas to be incomplete and the intake air not
sufficient. As a result, the working performance of
the cylinder becomes worse. Engine idle trembling.
Air intake problems may also cause computer
memory air flow meter fault code. If the fault is not
ruled out for a long time, it will make the oxygen
sensor workingin harsh conditions for a long time,
accelerate the damage of the oxygen sensor, and
cause the engine fault light to turn on.
Reason of high-water temperature
Water tank water depletion
The engine is cooled by water cooling, although
the coolant consumption in the water tank is slow,
there is also consumption. Some owners do not
check the coolant, the water tank is short of water
for a long time, resulting in high water temperature.
Some car owners find that the water temperature
rise after driving a few kilometers, and there was
no leak in the water pipe. This kind of fault may
be that thermostat cannot be opened, the car
cooling system cannot carry on a general
circulation, resulting in high water temperature.
Water pipe leakage
In the course of driving, if finding out where
the car has water leakages, check the water
pipe aging and breakage. It is easy to find it,
and you can replace the corresponding water
pipe at the maintenance shop.
Bad water tank heat dissipation
Some car owners directly use water as coolant.
Long-term use of water as the media will lead
to water rust in the engine and water tank, the
bad heat dissipation of the water tank leads to
high water temperature. Solving this problem is
to remove the rust first, then clean or replace
the water tank.
Water pump fault
The water pump is the core part of cooling system
in the car. Now most of the water pumps used in
car are blade-type. After working for a long time,
the blades will be polished away, which will cause
the water system does not circulate and the water
temperature is high.
Cylinder mattress is deformed
Some car owners reacted to the high water
temperature of the car, but actually there was
no water leakage when using the car. In addition,
a small amount of cooling water enters into the
engine due to deformation or damage of the
engine cylinder mattress. In this situation, the
coolant in the tank was consumed more quickly,
so there will be a water shortage in the water
tank after the car has been running for a while
and the water temperature is high.
Electronic fan failure
The heat from water tank on the car is emitted by
the rotation of the electronic fan. If the electric fan
does not work, the water temperature of the car will
The water temperature sensor on the car controls
the operation of the electronic fan in water tank.
If the water temperature sensor is faulty and there
is no signal to activate the cooling fan, the water
temperature will be rose.
The harness on the car is the core part
of the whole car. If the line is faulty,
it will indirectly lead to high water temperature.
Reason for low voltage：
The long-term idle car is the first reason to cause
the low voltage of car battery. Because of the
internal structure, specific gravity, temperature
and material impureness of the car battery, the
battery will often self-discharge, and will usually
be discharged 0.5~1% of electricity in one day.
If the car is not used for a long time, it will easily
lead to excessive battery discharge and be unable
to continue charging.
Nowadays, ordinary car batteries generally was
designed as lean liquid type. The moisture in the
electrolyte will be gradually volatilized, and white
lead sulfate will be gradually formed. After the
internal electrode of the car battery is severely
sulfated, recharging the battery cannot restore
its capacity, and hydration is also not enough.
Since the interior of the car battery is a purely
chemical reaction, its main principle is to store
electrical energy into chemical energy storage.
When the discharge is required, the chemical
energy is converted into electrical energy.
Therefore, the battery has a service life limit due
to technical problems. The service life of a typical
battery is basically only 300 times of charging
and discharging. When the service life is
almost the same, the voltage will be too low.
Reasons for high oil pressure
Oil viscosity is too large
The oil viscosity indicates the amount of internal
friction resistance when the oil flows. The oil
viscosity is related to the engine temperature.
When the engine temperature is low, the viscosity
of the oil is large. Conversely, when the engine
temperature is high, the oil viscosity is small. When
oil viscosity is large, the fluidity is poor, but the
leakproof is good, and the leakage amount is small.
If the oil viscosity exceeds the specified value,
the flow resistance of the oil in the lubrication
system will be increased. At the same, the pressure
will be increased. This shows that the engine
temperature is low or the oil viscosity is large,
the oil pressure will be high. Because the oil grade
is not properly selected, that is the oil grade is not
suitable for the ambient temperature. For example,
the large oil viscosity for summer is selected
The gap of pressure lubrication part is too small
or the oil fine filter block the lubricating oil to flow.
It shows that the flow resistance of the lubricating
oil circulation circuit is equal to the sum of the
reciprocal of the parallel branch oil flow resistance.
If the matching clearance of the camshaft journal,
the connecting rod journal, the crankshaft journal
and the rocker shaft on the pressure lubrication
part is too small and the filter element of the fine
filter is dirty, the oil circuit will be blocked. And if
the pressure of the pressure limiting valve is
adjusted too high, the flow resistance of the
lubricating oil circuit will be increased and the
pressure will be increased.
The pressure of the pressure limiting
valve is adjusted improperly
According to the composition and working principle
of the pressure limiting valve, the pressure limiting
valve relies on the balance spring and the ball valve
to limit the oil pressure, and the oil pressure does
not exceed the specified value of the technical
documents. When the oil pressure exceeds the
specified value, the valve is pushed away from the
spring by the spring force of spring to relieve
pressure in the system. When the oil pressure is
lower than the spring force, the valve is closed with
the action of the spring to limit the pressure within
the specified range. From this point of view,
the oil pressure in the lubrication system depends
on the spring force of the spring. If the adjusted
spring force is too large, the oil pressure in the
system will be too large.
Engine oil filter is blocked
When the oil filter is clogged and the oil cannot be
flowed, the safety valve installed on the filter base
is opened and the oil will directly flow into the main
oil passage without filtering. If the opening
pressure of the safety valve is too large, it cannot
be opened in time when the filter is blocked.
Therefore,if the pressure of the oil pump is
increased, the internal leakage will be increased,
and the oil supply to the main oil passage is
correspondingly reduced, which will decline oil
pressure. It should be always kept the oil filter
clean; Adjust the opening pressure of the
safety valve correctly (it is generally 0.35-0.45Mpa);
Replace the spring of the safety valve or the mating
surface of the grinding steel ball with the valve seat
in time to restore its normal working performance.
Reasons for low intake pressure
Air demand is greater than supply
Check if the valve on the air supply pipe is open
or not, if there is air leakage on the system or not,
which reduce the air consumption.
Oil and gas separator is blocked
Due to more or less impurities in the oil system,
the filter element will be blocked after it is operated
for a period of time, which will increase the
resistance of the compressed air through the filter
element and affect the normal operation.
Therefore, the operator should replace the filter
element in time according tothe signal displayed
on the monitor panel.
Air filter is clogged
The air filter is to filter the inhaled air to ensure
that the air entering into the air compressor is
clean. If the air filter element is clogged, it will
affect the intake air volume of the machine.
Therefore, it is necessary to replace its filter
element in time.
Pressure regulator is malfunctioned or damaged
The pressure regulation system is to automatically
adjust the compressor according to the amount of
gas used by the customer in order to achieve a
alance between supply and demand. Therefore,
it is necessary to replace the damaged pressure
regulator in time, and adjust the malfunctioning
pressure regulator in time.
Air intake valve is not fully open
The intake valve is to control the amount of intake
air. When the machine is running at full load,
the intake valve is fully open. When the amount of
gas required by the user is reduced, the device of
air volume adjusting will input compressed air to
the intake valve to reduce the opening degree of
the intake valve, which will reduce the intake air
amount of the compressor. The Intake valve
failure will affect the load on the unit.
Control line is leaked.
Air leakage from the air compressor control line
will prevent the intake valve from opening
completely so that the unit load cannot be