Wheel, Balancing
Wheel, Balancing
Before beginning balancing, the following requirements must be fulfilled.
• Tire inflation pressure must be OK.
• The tire tread must not be worn down on one side and should be at least 4 mm deep.
• The tires must not have any damage such as cuts, holes, foreign bodies, etc.
• The suspension, steering, tie rods and damper must be in proper working order.
• A road test has been performed.
Wheel, Balancing on Stationary Balancing Machine
• A test drive was performed. Refer to => [ Road Test, Performing Before Balancing ] Road Test, Performing Before Balancing.
Tension the Wheel on the Balancing Machine
• Please keep in mind that cleanliness is the most important when balancing as well, just as for any other repairs you perform. Only then can a proper result be obtained!
Dirt and rust in the area of the contact surfaces and centering of the wheel distort the result.
- Clean contact surfaces, centering seat and wheel disc using the pneumatic brush grinder set (VAS 6446) before tensioning the wheel on the balancing machine!
• It is very important that the wheel balancing machine uses the correct system for centering and tensioning the tires when replacing them. Reference the information for the wheel balancing machine centering system before beginning any work.
- Tension the wheel with the tire on the balancing machine.
• To mount the wheel on the wheel balancer, use for example, the wheel balancing machine centering system (VAS 5271).
• This way a 100% centering of the wheel and gentle mounting is possible!
• It is not possible to center it 100% on the balancing machine with conical tensioners.
• With a deviation of 0.1 mm outside the center, there is an imbalance of 10 grams on the wheel/tire.
Wheel/Tire Balancing Procedure
- Let the wheel and tire rotate on the wheel balancer.
- Check the run of the characteristic lines on the sidewall of the tire in the area of the rim flange.
- Check the tire wear pattern while the wheel and tire are rotating.
• In the event of one-sided wear, flat spots from braking or severe wear spots, smooth running cannot be achieved by balancing. In this case, the tire must be replaced.
- Check the run out of the wheel and tire. If the wheel with tire runs untrue although there are no flat spots, a radial or lateral run out may be the cause.
- Check the wheel with tire for radial and lateral run out. Refer to => [ Tire and Wheel Radial and Lateral Run Out Checking, using a Tire Dial Gauge ] Tire and Wheel Radial and Lateral Run Out Checking, using a Tire Dial Gauge.
- If the radial and lateral run out are within the specified tolerance, balance the wheel and tire.
• Do not use more than 60 grams of weight per wheel.
• If more weight is necessary, a smoother running can achieved by matched mounting of the tire. Matched mounting of tire. Refer to => [ Wheels and Tires, Matching ] Wheels and Tires, Matching.
• The display in the balancing machine should show 0 grams.
• road force measurement system (VAS 6230 A) can be inserted as an alternative to matching. Refer to => [ Vibration Control System ] Vibration Control System.
- Bolt the wheel to the vehicle.
- First, tighten the lowest wheel bolt by hand to approximately 30 Nm.
- Now tighten the remaining wheel bolts diagonally also to about 30 Nm. This process centers the wheel on the wheel hub.
- Put the vehicle on its wheels.
- Now use a torque wrench to tighten the wheel bolts diagonally to the specified tightening specification.
Road Test, Performing
- Perform a road test after balancing wheel/tire.
If a vibration is still detected during the road test, the cause may be due to tolerance in the wheel centering.
The component tolerances of wheels and wheel hubs can be additive in unfavorable cases. Vibration can result from this. This can be eliminated using a finish balancer.
Wheel, Balancing with Finish Balancer
• Working with a finish balancer requires instruction from the manufacturer of the balancer.
• For the balancing, the wheels of the tractive axle are set upon the turntable sensors, for example, front wheels for Front Wheel Drive (FWD) and all 4 wheels for All Wheel Drive (AWD).
If it is determined when balancing on the vehicle the remaining imbalance is more than 20 grams, the wheel should be rotated on the wheel hub.
- Mark the point at which the imbalance is indicated.
- Afterwards, unbolt the wheel and rotate its position on the wheel hub so that the marking points downward.
• The wheel hub must not turn during this procedure.
- First, tighten the lowest wheel bolt by hand to approximately 30 Nm.
- Now tighten the remaining wheel bolts diagonally also to about 30 Nm. This process centers the wheel properly on the wheel hub.
- - Check again whether the imbalance is less than 20 grams using the finish balancer.
• The imbalance should not be smaller than 20 grams under any circumstances before changing balance weight.
- Remove the wheel bolts again if necessary.
- Rotate the wheel relative to the wheel hub once more by one or two wheel bolt holes.
- Tighten the wheels using the method described above.
• The imbalance should only be reduced by changing balance weight if the imbalance is less than 20 grams.
- Balance the wheels until the imbalance is below 5 grams.
- Tighten the wheel bolts to the specified tightening specification if you have not already done so.
Always tighten the wheel bolts to the specified tightening specification using a torque wrench.