Porosity of alloy wheels
Such repair of disks for which welding, heating or forging is not allowed.
1. Raise the vehicle and place it on the supports provided for this purpose.
2. Remove the tire and wheel assembly. See section in this part «Wheel».
Attention! To avoid serious injury, do not stand next to the tire while it is being inflated, as the tire bead may rupture when jumping hard over the collar (hump). Do not increase pressure in a tire of any dimension to more than 275 kPa (40 psi inch), until the tire beads are in place. If at a pressure of 275 kPa (40 psi inch) the tire beads do not snap into place, bleed the air out of the tire. Lubricate the tire beads. Re-inflate the tire. Excessive air pressure in a tire can cause a bead rupture and an accident.
3. The location of leaks can be determined by inflating the tire to a pressure of 345 kPa (50 psi inch) and lowering the tire and wheel assembly into the water.
4. Mark the leaks and remove the tire from the wheel.
5. Sand the inside of the wheel at the leak with grit sandpaper (grit) 80. Clean the leak with some common cleaner.
6. Apply a 3.3mm layer of adhesive/sealant to the leak (0.13 inch). Leave for 12 hours to dry.
7. Install the tire on the wheel. Inflate the tire to a pressure of 345 kPa (50 psi inch) and check for leaks according to step 3.
8. Adjust tire pressure according to specifications. See section in this part «Tire size and air pressure».
9. Balance the tire and wheel assembly. See section in this part «Wheel and tire balancing».
10. Install the tire and wheel assembly. See section in this part «Wheel».
11. Lower the car.
Restoration of the protective coating of light-alloy wheels
A clear or colored protective coating is applied to the surface of light alloy wheels by their manufacturer. If this clear coat is damaged or removed, the physical properties of the surface may begin to deteriorate. This can occur in some automatic car washes that use silicon carbide-tipped brushes to clean white surfaces and tires. Once the protective coating has been damaged, further deterioration of the surface will occur under the influence of caustic detergents and salt, which is sprinkled on the roads. The following describes how to remove dirt, clean and resurface alloy wheels.
Before repairing alloy or clearcoat damage, the wheels and tires must be prepared.
1. Remove the wheel from the car.
2. Mark the position of the weights on the outside and remove them.
3. Wash the wheel inside and out with a water-based all-purpose cleaner. Remove grease and oil with solvent.
4. Protect the tire before coating.
5. Using wet or dry grit sandpaper (grit) 400, sand the painted areas that do not need to be repainted. Sanding will improve the adhesion of the clear coat.
Alloy damage on wheel surfaces
1. Place the wheel on the brake grinder and rotate slowly.
2. Sand the wheel using the sandpaper pad. Hold the pad parallel to the surface of the wheel and move slowly back and forth from the center to the outer edge of the tire, repairing any damage. Use sandpaper of the specified grit (grit) in the following sequence:
- grit 80.
- grit 150.
- grit 240.
Clear coat damage on unpainted wheels
1. Apply a chemical cleaner. Use a small 1/4" brush to apply around the perimeter, around the needles, and similar areas (6.5mm).
2. Remove the cleaner following the manufacturer's instructions.
Attention! To avoid serious injury, do not use the motor to turn the wheel while grinding.
3. Using grit sandpaper (grit) 240, grind the wheel by slowly turning it on a brake grinder or by placing it on the car and turning it by hand. Grinding restores the appearance that the surface had after machining and improves adhesion.
4. After repairing the metal surface or a clear coat, the wheels must be recoated.
Coating procedure
Attention! To avoid serious injury when applying any two-component paintwork, follow the manufacturer's recommended precautions. Failure to follow these recommendations may cause lung irritation and an allergic reaction of the respiratory system.
1. Clean the surface.
2. Moisten the wheel with a chemical cleaner for 1 to 3 minutes. Rinse the wheel with water and dry.
3. Moisten the wheel with the chemical compound to obtain a coating for 1 to 3 minutes. Rinse the wheel with water and dry.
4. Apply Urethane Additive by following the 3 steps below.
1st coat - Apply a thin layer by spraying with a thin spray and dry.
2nd coat - spray or brush a thin layer and dry.
3rd coat - Spray or brush on a thick double wet coat and dry.
5. Leave the urethane coating to dry for 24 hours or flash dry for 30 minutes and then dry for 30 minutes at 60°C (140°F). Allow the urethane coating to cool for 5 minutes before installing the wheel on the vehicle.
5. Leave the urethane coating to dry for 24 hours or flash dry for 30 minutes and then dry for 30 minutes at 60°C (140°F). Allow the urethane coating to cool for 5 minutes before installing the wheel on the vehicle.
Balancing with dismantling from the car
Perform wheel balancing using an electronic wheel balancer for wheels removed from the vehicle. The balancing stand is easy to operate and provides both static and dynamic balancing. Unlike on-vehicle balancing, off-vehicle balancing does not correct the imbalance of the brake drum or disc. This shortcoming is compensated by the accuracy (usually within 3.54 grams (0.125 oz)). Fix the wheel on the stand with a cone inserted into the central hole from the inside of the wheel; do not use the wheel bolt holes for this.
Tire imbalance correction
There are two ways to correct pre-balanced tires that continue to vibrate. The first method is to use an automatic stand that loads the tire and grinds off small amounts of rubber from the raised points on the two outer tread tracks. The correction made by this method usually does not disappear and, if performed correctly, does not significantly affect the appearance or life of the tire. Tire dressing on a stand equipped with knives is not recommended due to a significant reduction in tread life and the frequent need for repeated dressing.
The second method is to remove the tire and install it on the rim after a 180 degree turn. This method should only be used on tires and wheels that are known to cause vibration, as using it on balanced assemblies is likely to produce vibration just as well.
Selection and installation of wheels and tires
Selection and installation of tires and wheels is carried out at the assembly plant. Selection-assembly ensures alignment of the most rigid part of the tire in the radial direction (or prominent point), with that part of the wheel, the radius of which is the smallest (or in which there is a depression).
The protruding point of the tire is marked with red paint by the manufacturer or indicated on a label affixed to the outer sidewall.
The cavity of the wheel will be located at the location of the valve.
Before removing the tire from the wheel, mark the location of the valve on the tire to ensure subsequent installation in the same position.
New tires that are of the same quality as those installed at the assembly plant will also have raised and trough marks in the same way.
Mounting and dismounting tires
Note: A tire changer should be used to mount and remove tires. Follow the equipment manufacturer's instructions. Do not use hand tools or tire changers to change tires. These tools can damage the tire beads or the wheel rim.
1. Scrub the rim seat with a wire brush or a rough steel wool to remove grease, old rubber or light rust. Lubricate the tire bead with a tire lubricant before mounting or removing a tire.
Attention! To avoid serious injury, do not stand next to the tire while it is being inflated, as the tire bead may rupture when jumping hard over the collar (hump). Do not increase pressure in a tire of any dimension to more than 275 kPa (40 psi inch), until the tire beads are in place. If at a pressure of 275 kPa (40 psi inch) the tire beads do not snap into place, bleed the air out of the tire. Lubricate the bead again and inflate the tire. Excessive air pressure in a tire can cause a bead rupture and an accident.
2. After mounting the tire, inflate it until the beads are in place. Never use a pressure boost above 275 kPa (40 psi inch) for the boards to fall into place.
3. Install the valve and inflate the tire to the required pressure. Make sure that the bead mounting ring is positioned around the rim flange and visible from both sides of the wheel. This position of the tire ensures that the tire rim is in place.