Diesel! In China, most of them are existing as the operating vehicle, and as a private car, it is the gasoline vehicle. Especially high-end brands: such as the BBA series, most of them are gasoline vehicles, and the diesel cars are there, but they are not the main product.
The advantages of diesel vehicles have a lot, power, fuel consumption provinces, and discharge is also clean (black smoke is only surface phenomenon, “harmful substances are much smaller than gasoline vehicles), but domestic riders have formed a diesel car, which is mainly The hang concept has led to a state in which domestic passenger cars is not honest. In fact, there are many domestic vehicles in Europe.
Today, there is such a diesel Audi Q7, an engine is a problem, leakage oil, slight burning oil, abnormal noise … Because the usual repair is the petrol engine, this time, everyone has encountered the diesel, everyone must think that it will be tricky. Not too! In fact, the diesel bus is not difficult to repair, but it is expensive, and it is difficult for things. Everything is not a problem.
At first glance, it is ordinary Q7, what is the difference.
The classic atmosphere of the old Q7 parking space is really domineering and horizontal.
Vehicle ID card. TDI is the meaning of diesel cars in the Volkswagen Audi system.
The number of kilometers, close to 20W, diesel car 20W is a hurdle, the wear of the wear, the three precision and the three-scale part have arrived. What is three precision dippins?
1. Plunger, plunger set. 2. Needle valve, needle valve body. 3. Oil valve, oil discharge valve seat. Of course, the current diesel car is a common rail design. The three precision dippers are streamlined into two components, one is the common rail high pressure pump, one is the injector.
Prepare to dismantle the engine, first disconnect all of the wire harnesses and lines. At the same time, listen to the owner said that the high-pressure pump and 6 injectors have changed, this is worthy of our maintenance.
Take out the machine, the oil is not much less, this car is mainly a leakage oil and an abnormal sound, and the dynamic horse tiger.
Oil spill is everywhere. This 3.0 CRC code engine, the oil seal is easy to leak after the crankshaft, and we finally knew what is the reason for the crankshaft, which will be explained.
This hit the oil on the oil bottom shell, I am drunk, this method is really too bad.
Prepare an indentation
After the engine and the body are completely disconnected, raise the body and the engine is separated.
Lift up lift, engine and gearbox, good guys, good engine and gearbox.
This diesel engine, the head is really not small.
This leakage problem, what is expected
Although it is a big guy, it has been taken out, how to remove it horizontally, it is, not afraid of him.
Unplug the injector. The special tool for pulling the oil is doing it yourself. This injector is very tight, and it is bonded to the carbon. It is very powerful to pull it out.
During the decomposition, the cavity under the intake manifold, leaked the oil.
Disconnect the gearbox. The gearbox and gasoline truck are the 8AT gearbox of love, why don’t you use the 8AT of EF, it is estimated that the cost is considered.
The cover of the edge is removed, you can see the chain and the wheel, but to further disassemble, you need to remove the back cover.
After dismantling the flywheel plate, the screws of the flywheel plate were found to be a lot of black glue. This screw itself needs to be rubber water, but must be threaded, since the black glue of the launcher is hit, the description is being moved. It is estimated that the oil can be searched before, and some people have been removed from the oil seal.
After the removal, I found that the rear oil seal was leaking. This engine is easy to oil, there are two reasons, one is the oil seal material problem, and another will talk about it, you are patient.
Take the back cover, see the chain system, is also very simple in timing, and several hole bits can be fixed with the positioning pin.
Remove the chain
Take off the camshaft and check the valve rocker arm and the top tube. The owner reflects that there is a sound of the car after the car is started, but it will disappear for a while. I suspect that the hydraulic head is bled.
Squeeze the hydraulic head cylinder with your fingers! Pressure is very powerful, there is no resistance, and you must change the top.
Take the cylinder head and see the combustion chamber. The combustion room of the diesel car is characterized by a word, black! After all, the diesel car is burnout the carbon particles.
Each cylinder has a preheating plug, but one of the heads has been broken and must be replaced.
The engine is decomposed for seven or eight eight.
Lift the engine, leave the sub-frame and the differential on it.
Continue to decompose the cylinder and get off work.
First remove the bottom shell.
See the big saver
Decompose the crankshaft, connecting rods and pistons
Take a piston, this piston, a boss
This is the piston of the diesel car, the main point than the gasoline car, and the piston ring is thick than the gasoline vehicle. At the same time, the third oil ring is also blocked by carbon.
The whole master of the local boring is pulled away.
And we, also take this free time, clean the sub-frames and differentials of the sheath.
The valve pole of the diesel car is not only strained, but also wear, the valve catheter clearance is very large.
Everything will throw it into the ultrasonic pool to do clean and say
All of these hydraulic top pillars have to be changed, and 24 all cars are changed.
This engine hydraulic bracket is pressed by the engine for a long time, and it has been collapsed and it is almost flattened.
The things that ultrasonic washed back, we have to make further cleanup, this is a heavy live.
The most evil thing is that the repairman who has repaired this car, the screw is broken, and it is not installed. Every broken screw, we all take it out and match the new screw.
Because the piston size of this car is special, I have to customize the set of installed pistons, let the big brother of the local lathe have one.
In order to ensure the smoothness of the tool and the accuracy of the size, the lathe is fine grinding, and a tool making must spend much money.
Waiting for two days, from Beijing SF sent valve catheter and valve. This catering tube is not provided. If the gap is large, the cylinder head is directly changed, more than 30,000, who eats.
This valve pole is not cheap. You think it is an EA888 gas, dozens of money is enough, this car’s valve, the price of 155, the pit you have not discussed.
Replace all valve catheters.
Check valve red printing
Grinding valves achieve best sealing
Finally, the valve oil seal of the double sealing is installed, so that it is not worried that the cylinder head portion will cause the burning oil.
The next is the torque. I didn’t want to be boring, but I couldn’t live with 20 filaments. Why did this car crankshake after the crankshave is easy to oil, which is one of the reasons. Because the amount of cylinder wear is large, the amount of crankcase is also large, the engine is large, the exhaust gas is squeezed out from the seal and other seals, which will cause oil leakage.
The cylinder of this diesel car is very long. It is clear that the hole is very deep. The ordinary cylinder line is not enough. Here is the cylinder set of imported excavators, which is also bindered separately, and it is delayed for two days.
Continue the tank, inlaid, the master said that this cylinder is too hard, the cutter is not eliminated, and it is necessary to have a knife.
Finally, the cylinder wall is finally grinded to the most accurate size and surface roughness.
Next, we firmly confirm another problem, this two rings are old piston ring, now the cylinder is standard size, we put in the old rings in, found that the opening clearance of the first ring is reasonable, but the second road The opening clearance of the ring has nearly 80 wire, such a large opening gap, which causes the crankcase to be very powerful, resulting in the oil sealing oil.
With a new piston ring. This piston ring is custom-made, the original production is not found, so some is a set of bags. Later, I contact the friend of the Piston Ring Factory directly, let the Yizheng a factory specializing in the diesel activist to help me make a 83mm ring.
Install new big watt
Put on the crankshaft
Put the tile
Hey, the tools you have done can be used in the field.
Very comfortable to get into the piston
Tighten the small tile bolts according to the specified torque.
Install the middle shell.
Install the oil pump.
Install the oil splash.
The crankshaft is locked with a special tool.
Install the oil housing, the oil housing screw is replaced, and there is a clean place before the glue.
The oil level sensor seal is replaced.
Put oil level sensor
The cylinder turns over
Install high pressure pump. The owner has changed before, and it looks quite new.
Install oil cooler
The front cover is sealed with a sealing strip, a new sealing strip
Install the front cover, this thought can be easily set, but the tragedy has happened.
The original aluminum screw has been broken.
Substitution with the iron original screws of Audi other models, this is the most feasible solution.
The most depressed thing is that there is a breaking screw break in the hole, there is no way, it can only be patient with the fine drill bit.
Then inlaid the threaded sleeve.
Excessive bolts all use line cut to cutly cut into specified sizes
After installing the front cover, it is the installation of the crankshaft oil. Use a special tool to guide the installation of the crankshaft oil seal.
Use the customized tool to knock the oil seal to the specified position.
Ha, perfect installation
Install a new machine oil base
Watch cylinder pad
Two-side cylinder head is in place
Tighten the cylinder bolts according to the specified torque
All hydraulic top columns
The preheat is installed, one of which is new
Install a good time chain
Installed back cover
There are two kinds of oil after the crankshaft, a soft, a hard, I choose hard, not easy to oil.
Guide the installation of the special tool
Perfect installation, oil seal
There are two small covers behind the cylinder head, don’t forget
Install the exhaust gas recirculation system
The two-sided valve chamber cover is installed, this valve room is expensive, paying price 1700+
Most of the engine part is done
Install the turbine. After 150,000 kilometers, the turbine is basically a problem. This car is no exception, but this car turbine is a five-digit price, because the bad is not very powerful, so it is not changed.
The seal of the injector is three major pieces, one-time replacement. Shave the carbon of the surface of the injector before changing.
Install the injector
Install intake manifold.
Many of this car is torped in the cabin all year round, many of which are aging, and some line leather fall off, so bad plugs, all have to be replaced.
Arrange the harness, the engine is basically almost
Put the generally loaded engine and place the crane on the sub-frame.
The two engine support pads on the subtle carriage must of course be replaced. Although the appearance looks similar to the gasoline car, it is actually different.
Install engine bracket pad
Go on the engine
Next is the gearbox, the crane crane, and the engine docking
Both perfect docking
All belts and wheels in front of the engine have changed new, it looks very refreshing, and the oleasaw of the greasy uncle before it changed.
After the assembly is completed, ready to enter the cabin
Slowly put down the body.
Engine enters the cabin
Fixed the bottom screw, the engine will not fall. Because the part is unyfamed before, it is still a bit greasy, it doesn’t matter, it can be washed below.
Connect good wiring harness and pipeline.
Add oil, we use 0W40 black diamond Move oil
The exhaust pipe comes out of a blue smoke, then a black smoke, then there is no smoke.
After inspection, it is found that several electrical appliances have faults, and the fault code is deleted, especially this thermostat solenoid valve.
That is, this solenoid valve. To verify this problem, we inserted with the EA888 turbine solenoid valve N75, the fault code can be deleted, indicating that the original car’s solenoid valve inside the coil does have problems, decisive order, Beijing delivery.
Other work is not delayed, adding cold media, 1050 grams, using the cold media of Japanese electricity.
The new solenoid valve is in, and it is two days, the diesel car is an accessory.
Everything is ready, I don’t hurry out, do four rounds of positioning, after all, have been moved by the sub-frame, the parameters are definitely wrong.
Data debugging …………
I am busy preparing to test the truck, it is already a night. It is also this traffic light. The opposite KTV’s little sister is estimated to go to work.
Prepare high speed
On the high speed, a horse Pingchuan, actually no car, sprinkled the joy. The torque and motivation of the diesel vehicle are reflected in the high speed.
A perfect test, under high speed
The next day, the riders took the high-speed rail from Changsha, perfect delivery!
After reading it, is you like me, a few questions need to answer?
1. Why is this carava after the crankshaft?
A: Because the piston ring opening clearance is large, plus the cylinder wear is powerful, resulting in a large amount of crankcase, the seal is high pressure gas impact, easy to oil, and this diesel car oil seal is soft, the strength is not enough, so it caused a leak Oil.
2. Is the second-hand diesel car suggest buy?
A: The diesel car is very cool, and the failure rate is not high. But once there is a problem, it is a monk. Maybe you buy it quapu in second-hand, but it’s not cheap, you have to think about it.
3, is it difficult to repair the diesel car, can you fix it?
A: Just give me enough original parts and improvements, the special tools are complete, and it will definitely be repaired.
This diesel Q7 has been carefully repaired, basically restores youth, but turbocharged is always a bit problem, the owner said that the problem is very bad, directly buy a new turbine or shake, there is a lot of energy turbine core repair turbines. The god, when they let them help solve. If so, then it is really like tiger.
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