In detail: do-it-yourself turbine repair by a real master for the site my.housecope.com.
For many car enthusiasts who love power and speed, the question of buying a car with a turbocharged engine is very important.
In turn, the task of the turbocharger is to supply a larger volume of air to the engine cylinders and, as a consequence, increase the power of the latter.
The only drawback of such a useful element is frequent failure, so every motorist should be able to make at least minimal repairs to the turbine.
Structurally, a turbocharger is a very simple mechanism that consists of several basic elements:
General body of the node and snail;
Plain bearing;
Thrust bearing;
Distance and thrust bushings.
The turbine housing is made of aluminum alloy and the shaft is made of steel.
Therefore, in the event of failure of these elements, the only correct solution is only replacement.
Most turbine damage can be easily diagnosed and repaired. At the same time, the work can be entrusted to professionals in their field, or you can do everything yourself.
In principle, there is nothing complicated about this (we will consider how to dismantle and repair a turbine in the article).
As the operating practice shows, there are two main reasons for breakdowns - poor-quality or untimely maintenance.
If, however, a technical inspection is carried out according to the plan, then the turbine will work for a long time and without any particular complaints from motorists.
So, today there are several main signs and reasons for turbine failure:
1. The appearance of blue smoke from the exhaust pipe at the time of increasing revs and its absence when the norm is reached. The main reason for such a malfunction is the ingress of oil into the combustion chamber due to a leak in the turbine.
Video (click to play).
2. Black smoke from the exhaust pipe - indicates the combustion of the fuel mixture in the intercooler or delivery line. The probable cause is damage or breakdown of the TKR (turbocharger) control system.
3. White smoke from the exhaust pipe indicates a clogged turbine oil drain line. In such a situation, only cleaning can save.
4. Excessive oil consumption up to one liter per thousand kilometers. In this case, you need to pay attention to the turbine and the presence of a leak. In addition, it is advisable to inspect the joints of the pipes.
5. The dynamics of acceleration is "dulled". This is a clear symptom of a lack of air in the engine. The reason is a malfunction or breakdown of the TKR control system (turbocharger).
6. The appearance of a whistle on a running engine. The likely cause is an air leak between the motor and the turbine.
7. Strange grinding noise during turbine operation often indicates the appearance of a crack or deformation in the housing of the unit. In most cases, with such symptoms, TCR does not "live" for a long time and further repair of the turbine may be ineffective.
8. Increased noise in the operation of the turbine can cause clogging of the oil line, changing the rotor clearances and rubbing the latter against the turbocharger housing.
9. An increase in exhaust gas toxicity or fuel consumption often indicates problems with the supply of air to the TCR (turbocharger).
To repair the turbine with your own hands, it must be dismantled.
This is done in the following sequence:
1. Disconnect all piping that leads to the turbine. In this case, you should be extremely careful not to damage the node itself and the devices adjacent to it.
2. Remove the turbine and compressor volutes. The latter can be dismantled without problems, but the turbine volute is often attached very tightly.
Here, dismantling can be done in two ways - by the mallet method or by using the snail mounting bolts themselves (by gradually releasing them from all sides).
When performing work, you must be very careful not to damage the turbine wheel.
3. Once the work on dismantling the volutes is completed, you can check for any shaft play. If the latter is missing, then the problem is not with the shaft.
Again, slight lateral play is acceptable (but not more than one millimeter).
4. The next step is to remove the compressor wheels. Pliers come in handy to do this job. When dismantling, please note that the compressor shaft has a left-hand thread in most cases.
A special puller is useful to dismantle the compressor wheel.
5. Next, the sealing inserts are dismantled (they are located in the grooves of the rotor), as well as the thrust bearing (it is mounted on three bolts, so there are no problems with removal).
6. Now you can remove the liners from the end part - they are fastened with a retaining ring (sometimes you have to tinker when dismantling).
The plain bearings (compressor side) are secured with a circlip.
7. When performing dismantling work, it is necessary (regardless of the breakdown) to rinse and clean the main elements - cartridge, seals, rings and other components.
Once dismantling is complete, repairs can be made. To do this, there should be a special repair kit at hand, which contains everything you need - inserts, hardware, oil seals and rings.
Check the quality of the fixation of the nominal liners. If they are loose, then they need to be grooved and the shaft should be balanced.
In this case, it is advisable to clean the liners well and lubricate them with engine oil.
The retaining rings located inside the turbine must be installed in the cartridge. At the same time, make sure that they are in their place (in special grooves).
After that, you can mount the turbine liner, having previously lubricated it with engine oil. The liner is fixed with a retaining ring.
The next step is to mount the compressor liner, after which a well-lubricated liner can be inserted.
Next, put a plate on it and tighten it well with bolts (without fanaticism).
Install the dirt plate (secured with a retaining ring) and an oil scraper ring.
It remains only to return the snails to their place. That's all.
This article provides a general algorithm for disassembling and assembling a turbine. Of course, depending on the type of the latter, this algorithm will be partially changed, but the general course of work will be identical.
Well, if a serious breakdown is revealed, then it is better to immediately replace the old turbine with a new one.
In the absence of serious defects, the repair of the turbine takes no more than a few hours. But with the help of improvised tools and material prepared in advance, you can make a very high-quality and budgetary repair.
The ZIL-5301 car began production in 1996. Its design took into account the market need for a compact medium-duty truck.
The reviving business activity after a period of stagnation has created a large niche for this class of vehicles. This tendency was caught by the management of the Likhachev plant.
In the design of the ZIL-5301 vehicle, the components and assemblies used on previous trucks were used to the maximum. The car was equipped with MMZ in-line diesel engines of various modifications. These motors were equipped with domestically produced turbochargers. Over the years, various modifications of turbochargers were installed, such as: TKR-6, TKR-6.1, TKR-6.5.1, TKR-7 and TKR-7.1.
These turbochargers differed among themselves in some geometrical parameters and maximum rotational speeds. In general, the design and principle of operation were identical.
The turbocharger has a good resource. This is due to the large margin of safety inherent in its design and the relatively low loads that it experiences during operation. In contrast to the good resource, the large mass of the turbocharger acts.
Like any part of a car, a turbine is subject to wear and tear. The article will consider the process of repairing a turbocharger of a ZIL-5301 car and everything connected with it.
The design of the turbocharger on the car in question is slightly different from the generally accepted scheme, according to which the vast majority of turbines of foreign cars are built.
The turbine consists of two body parts called a hot and cold volute. Impellers are located in the working cavities of these snails.
The hot volute is connected by the inlet end to the outlet manifold. A downpipe is attached to its outlet end.
There are two lines attached to the cold snail. One pipe goes from the air filter and supplies air to the turbine. The second is connected to the intake manifold and transfers air under pressure to the intake manifold.
The two body parts of the turbocharger are connected via a cartridge. The rotor shaft rotates in the cartridge on plain bearings. The rotor is rigidly connected to the impellers. The cartridge has two oil holes. One is connected to the working line of the engine lubrication system. Through it, the bearing unit is lubricated. The second oil channel is a drain channel. Through it, the oil from the cartridge cavity is drained into the engine sump.
To control the normal operation of the turbocharger, there is a system for limiting the supply of exhaust gases to the turbine wheel. The system works through a pneumatic cylinder that opens the valve of an additional channel that bypasses the hot impeller. The cylinder is powered by the pressure created in the intake system. When the pressure reaches a certain limit, air presses against the valve diaphragm. The valve applies force to the stem, which opens the bypass channel in the body of the hot volute. Exhaust gases rush past the impeller, which reduces its rotation speed and the pressure created in the intake manifold.
There is an additional safety system against critical overpressure in the intake system. This system was implemented by introducing a bypass valve, which opens when an unacceptably high pressure is reached and bleeds excess air back into the circuit in front of the turbine.
In addition to normal wear and tear, there are several main reasons that can damage a turbocharger prematurely.
Let's consider the main ones:
Grease supply problems. If, for any reason, the lubricant is no longer supplied to the bearing unit or the amount is insufficient, the turbine will fail very quickly.
Malfunctions in the fuel supply system or the gas distribution mechanism can lead to an increase in the temperature of the exhaust gases to unacceptable limits.
Worn engine parts or malfunction that causes engine oil to enter the combustion chamber. Oil combustion products quickly clog the working cavity of the hot snail.
Violation of the integrity of the air filter. Sand and other particles from the atmosphere enter the compressor section of the turbine and gradually destroy the impeller.
Worn cartridge seals. This leads to the penetration of oil into the working chambers of the turbine. From time to time, the oil under the influence of high temperatures begins to coke and contaminate the turbine.
Improper vehicle operation. In particular, the turbine is negatively affected by a sudden load on the engine without preheating or an abrupt stop of the engine from high rpm. The rotor shaft rotates under conditions of insufficient lubrication, which leads to rapid bearing wear.
Several major malfunctions of the ZIL-5301 turbocharger are known.
Consider the main breakdowns, as well as the signs by which these malfunctions can be identified:
Initial diagnostics are performed on a running engine. The sound of the turbine operating at different engine load conditions is assessed. The external condition of the turbine casing, branch pipes and joints is examined. The operation of the pneumatic cylinder and bypass valve is checked.
If at this stage there are suspicions of a malfunction, the turbocharger is dismantled.
After dismantling, the turbine and compressor parts of the housing are removed. Thorough cleaning of oil and carbon deposits is carried out. The condition of the working surfaces is examined. Cracks are unacceptable.
The integrity of the impellers is checked. If there is damage, the impellers are replaced.
The free movement of the rotor shaft is checked. The cartridge is inspected for oil leaks. If there are obvious faults, the cartridge is disassembled.
After disassembling the cartridge, the condition of its internal cavity is assessed. The surface of the shaft, which is in contact with the bearings, is inspected. If there are no critical workings, bearings and seals are changed. The cartridge is being assembled. The rotor shaft is being aligned.
The function of the bypass valve control hydraulic cylinder is checked. Repairs are made if necessary.
After eliminating all faults, the turbine is assembled and installed on the engine. A control check is done.
If there are no complaints about the work, a guarantee is issued.
