How to Balance a Tire with U-820 Wheel Balancer Machine

Tire/wheel assembly balancing is a very basic service, and still a good profit center for tire dealers who invest in the necessary equipment.

This article on how to properly balance tire and wheel assemblies with U-820 Wheel Balancer Machine.

Before a tire can be balanced, it must be concentrically seated. You can determine this by measuring the distance between the molded rib on the lower sidewall of the tire and the edge of the wheel’s rim flange. The tire must be deflated and reseated if the distance between the two points is greater than 2/32-inch.

After ensuring that the beads have reseated properly, the tire should be inflated to the recommended pressure.

1. Turn your machine OFF then ON, which resets the balancer. The machine wakes up using standard clip-on wheel weight locations.

2. Remove stones/rocks or other debris from tread and any weights already attached to the wheel. During this process you also should remove any mud, dirt or snow on the inside of the wheel and make sure that the mounting surface of the wheel is completely clean of debris.

3. Mount a tire/wheel assembly on a balancer that will use standard clip-on wheel weights. Use the most appropriate mounting meth­od. Technicians should be careful to avoid back injury and should seek assistance when lifting a heavy tire/wheel assembly onto a balancing shaft.

4. There are three main mounting methods. They include:

• Back Cone – Most original equipment and steel wheels can be mounted properly using this method. The wheel is centered on a cone from the inner side of the wheel.

• Front Cone – A wheel should be centered by the outer side of the hub only when the inner surface will not provide an accurate surface to center on.

• Pin-Plate – An alternate method of securing and aligning an assembly on a balancing machine is the pin-plate method. A pin-plate is added instead of a pressure cup.

5. Enter A & D wheel dimensions using offset arm.

Before a wheel can be balanced, wheel dimensions must be entered into the computer on your unit. These include:

A = Offset – The distance measured from the balancer (“0” on offset arm) to inner plane of the wheel rim (inner weight location).

W = Width – The width of the wheel at the rim flanges, measured with calipers.

D = Diameter – The diameter of the wheel as indicated on the tire.

6. For automatic measurement, pull the offset arm out to the wheel, hold it still at clip-on weight position against the wheel flange and wait for a “beep.” Return the arm to home position.

7. Enter the wheel width dimension. Use plastic calipers to measure wheel width for manual entry. Press the W key. Use the keypad to enter width value (between 2 and 20 inches.) Lower the hood for automatic measurement.

Note the value entry of the W dimension.

8. Lower the hood. The wheel will spin and unbalances are measured and displayed. The corrective weight amount appears in the weight display window for inboard and outboard weight locations.

9. Raise the hood after the tire stops rotating. Make sure that the wheel has stopped before raising the hood.

10. Inboard center bar blinks. If an inboard corrective weight is not required, the wheel will stop at the outboard corrective weight location and you can go to Step 13.

11. Attach inboard corrective weight. Attach specified weight amount at top-dead-center on the inside flange of the wheel. NOTE: Wheel weight suppliers often will supply a rim flange contour gauge to help technicians select the correct clip-on weight for the wheel.

12. Press NEXT, causing the wheel to rotate.

13. The outboard center bar will blink.

14. Attach outboard corrective weights. Attach specified weight amount at the top-dead-center on the outside flange of the wheel.

15. Lower the hood to respin the tire/wheel and check balance. The weight readings should now be 0.00.