Flywheel balancing is a necessary procedure to balance the rotating masses, eliminate inertial forces and ensure long-term operation of this part. If the rotating elements of an internal combustion engine are unbalanced, vibrations can occur, which significantly shortens the life of the engine and its components, such as the starter, driveshaft, and crankshaft.
The flywheel can be one of the sources of vibration, which is why it is necessary to balance it. This part engages the starter drive gear, which must be taken into account when preparing for the procedure for eliminating imbalance. Engine tuning also involves the use of a procedure such as grooving the flywheel. This manipulation involves removing the worn surface of the part, which is very important for its effective operation. Such grinding is an important balancing step to eliminate the negative impact of the manipulations performed on the operation of engine elements, such as the starter, crankshaft, and driveshaft.
Balancing Basics
Balancing is the process of returning the center of gravity to the geometric center of the flywheel. It is especially often carried out after the procedure for lightening this part, which is often practiced by motorists. Balancing is extremely important, otherwise destructive forces may act on the engine.
In the static case, some kind of mass appears on the axis of the part. Because of this, the axis of the device shifts relative to the axis of rotation, which leads to vibration. In the moment, additional masses appear at the edges of the part. If the flywheel does not move, then vibrations do not occur, but during rotation they can be extremely strong. The last option is dynamic. It combines the previous types of imbalance.
Often, to eliminate such problems, the car is taken to a service center. There, the flywheel is carefully balanced, returning the center of gravity to its original position. However, this procedure can be carried out without outside help, doing it at home. There are minimal difficulties here
Lever jerking and engine beating
In order to diagnose the need for balancing the crankshaft, it is enough to take a closer look at how the gear shift lever behaves when moving. If it clearly plays both on the road and at idle, then it’s clearly time to start repairing the engine.
An additional sign that crankshaft adjustment is no longer possible is noticeable vibration of the engine at idle.
Types of imbalance
In order to understand how the balancing procedure is carried out, you should understand the types of imbalance:
- Static. Develops as a result of displacement of the axis of the part in relation to the axis of rotation. This provokes vibrations.
- Moment. Possible when additional masses appear at the edges of the flywheel. In this case, the masses are balanced, but do not manifest themselves statically. However, when rotated, they provoke pronounced vibration.
- Dynamic. Determined by the combined action of static and moment imbalance.
Vibrations can increase or decrease depending on the rotation speed. They provoke additional load on engine elements (starter, driveshaft, crankshaft), and also lead to loosening of fasteners. In turn, this can lead to malfunctions and reduced service life and malfunctions of engine components: flywheel, clutch, crankshaft and others.
- incorrect manufacturing of engine components, such as flywheel, starter, crankshaft and others;
- heterogeneity of the material;
- inaccurate centering of fastened parts;
- increased clearances of fastened elements and assemblies, as well as non-compliance with alignment during installation;
- deformation of shafts during mechanical and thermal treatment and as a result of damage during use.
Vibrations can occur in the absence of balancing of both the flywheel and other parts of large diameter and significant angular velocity: the driveshaft, crankshaft, wheels and clutch.
Elimination of imbalance is carried out using specialized equipment in car service centers. Self-balancing is also possible. You just need to remember that before carrying out the procedure, you should disconnect the starter, which engages the flywheel, from the power supply.
Fig.1 Balancing the flywheel
Restoring old and new crankshafts
Most often, crankshaft balancing is performed on cars with many thousands of miles.
However, in some cases it is also necessary for relatively new cars, especially if they have driven a lot on hilly and rough terrain, which has led to the accelerated depletion of the power plant's life.
Carrying out balancing
Static balancing is easy and can be done at home. It is possible to balance the flywheel using auxiliary tools and equipment. First you need to remove the part, to do this you need to drive the car into the inspection hole, then turn off the power that the starter uses (it engages the flywheel), and only then remove the element.
It should be taken into account that hanging the flywheel freely leads to the installation of a position of the part in which the heaviest area will be localized at the bottom. To determine the position, the flywheel should be positioned so that it rotates freely on the supports. This can be done by securing the part to a shaft that is placed on supports.
At the same time, corners act as them. A vice is also used for this, in which a shaft with a flywheel mounted on bearings is clamped. It rotates under its own weight and is installed with the heavy section in the lower position. After this, the flywheel is grooved, that is, excess metal is removed from the heavy side (grinding).
In addition, balancing involves installing additional weight on the opposite side. This equalizes the distribution of masses. But flywheel grinding, or grinding, is a more common procedure. With its help, the heavy part of the part is lightened and the mass is balanced. After this, the flywheel is installed back, and the starter that hooks it is connected to power.
The dynamic balancing procedure should be carried out in a professional car service center. To implement this, specialized equipment is required. The peculiarity of the procedure lies in its joint nature: the imbalance is eliminated simultaneously for the flywheel, clutch and crankshaft. In this case, just as with static balancing, the power that the starter uses is turned off, which engages the flywheel.
Balancing the crankshaft and flywheel together
Thus, it is possible to balance the flywheel yourself - grinding is a fairly simple procedure, but dynamic balancing should only be carried out with the involvement of specialists, since it requires eliminating the imbalance jointly for the crankshaft, clutch and flywheel and involves a rather complex algorithm of actions using complex equipment and tools. In addition, grinding carried out in the service has a more positive effect on the operation of the car engine.
Reasons for shaft failure
Most often, crankshaft imbalance occurs for the following reasons:
- Poor quality of the crankshaft bed and a number of components adjacent to the crankshaft;
- Structural anomalies in the metal from which the crankshaft is made;
- Mutual collision of a number of parts due to their mechanical, temperature and corrosion deformation;
- Errors made during the layout of the motor;
- Inaccurate shaft centering;
- Its planned operational destruction.
Making a frame and installing nuts
The first step is to make the frame base of the machine. Its dimensions are determined by the length of a particular crankshaft. At this stage, the master will need pipes and profiles.
- Having welded a frame from them, grooves for the studs should be made in a couple of its corners and in the center of the tube located opposite.
- Nuts are attached to these places by welding, the threads of which correspond to the width of the studs.
Why does the part wear out?
Contrary to many popular opinions, one of the main reasons for the failure of a dual-mass flywheel is not the low quality of the part. Yes, not without this, manufacturers often make mistakes during production.
The main enemy of dual-mass flywheels is the excessively high torque of powerful modern car engines. They differ from older models in the high pressure that is formed in the fuel combustion chambers.
In addition, power units are manufactured by manufacturers from light alloys, which negatively affect reliability and cope much worse with vibrations.
Clutch pressure plate with housing assembly
The disk is balanced statically in a dynamic mode when installed on the working surface and two diametrically located holes for attaching the casing to the flywheel, as well as by drilling holes with a diameter of 13.8 mm in the bosses under the springs to a depth of no more than 23 mm. The distance between the supporting surfaces of the disk and the casing should be 9.8 mm with a parallelism tolerance of these surfaces of 0.03 mm. The residual imbalance should be no more than 0.005 Nm. After balancing, the mounting holes must be marked. For any re-installation along the same holes, the imbalance should be no more than 0.009 Nm.
Why restore?
First of all, the price, which plays a huge role. Depending on the complexity of the damage to the dual-mass flywheel, the cost of repair will be several times lower compared to purchasing a new flywheel.
If you are an experienced driver, then you understand that it is much better to restore an original part than to purchase a cheap Chinese fake, provided that the repair and restoration work is carried out in workshops that specialize in this area, have the appropriate experience in restoring flywheels and the appropriate equipment.
Our service offers high-quality and guaranteed restoration of a dual-mass flywheel. Most owners of cars with such flywheels have a negative attitude towards them and get rid of them at the first opportunity. However, not every driver realizes how well DMF improves driving comfort when driving a high-torque vehicle.
The final stage of machine assembly
Next, you should take four corners about a third of a meter long. Holes are made in them the same width as the diameter of the supports. Each pair of racks is crowned with a corner turned upside down, after which it is welded.
As a result, the car enthusiast will have something like a miniature gymnastic apparatus at his disposal. The crankshaft will be mounted on opposing U-shaped struts. You can start balancing.
Repair of dual-mass flywheels DSG from Automatic Transmission Service 24
We service all types of DMMs. Before starting maintenance, the technicians send the car for comprehensive diagnostics: computer, visual, hydraulic, mechanical. Based on the results of the diagnostics, an estimate is generated, agreed upon with the car owner, then the assembly mechanics begin to restore the DMM.
Repair of dual-mass flywheels DSG in our service includes:
- Removal of DMM.
- Disassembly of the device.
- Washing flywheel components.
- Grinding (including the clutch pressure plate).
- Replacement of the crown and all flywheel internals with new reinforced parts.
- Assembling the device, painting.
- Balancing the clutch pressure plate and clutch pressure plate.
After repairing the dual-mass flywheel, balancing and installing it, we carry out final diagnostics. The owner picks up the car after a test drive and checking the quality of technical service.
Do you want to get your DSG working again? Do you need to restore the gearbox DMM? Call the experts at Automatic Transmission Service 24: +7 926 733-34-83. We will send a tow truck for your car free of charge, carry out diagnostics, repair the dual-mass flywheel DSG and provide a warranty of up to 3 years.
Installation of locknuts and support posts
On the eve of balancing, the frame is set clearly horizontally. Once the alignment is complete, locknuts are screwed onto the nuts.
Then, next to each corner of the frame, grooves are made for four 25-centimeter rods, which will be the supports of the structure.
