Mounting Tyres

NOTIFICATION 

Wheel electronics 

• Wheel electronics unit and valve may have been fitted incorrectly. 
• Wheel electronics units may not have been assigned correctly. 

  Read and follow the installation instructions for the wheel electronics units.

  1. →

     > 443219 REMOVING AND INSTALLING WHEEL ELECTRONICS

     Check that the wheel electronics units are assigned correctly.

  2. →

     > Refer to appropriate Service Information

Information 

• For correct tyre mounting, always follow the instructions provided for the tyre removal/mounting machine. 
• Always use approved tyres a nd tyre sizes. (Specification code/speed index/load capacity). This data must be taken from the applicable/current Technical Information. 
• Tyre temperature during removal/mounting must be approx. 20°C (at least 15°C). If necessary, allow enough time to heat the vehicle/tyres in a suitable environment (at room temperature of more than 15°C). Example: If the room temperature of the workshop is approx. 20°C and the tyre temperature is approx. -15°C, approx. 3 hours are required to heat the tyres to the required temperature. 
• The wheel electronics must not be treated with compressed air, tyre mounting paste, cleaning agents or any other solvents. 
• Disc wheels with wheel electronics must not be cleaned with a high-pressure power cleaner before tyres have been fitted. 
• The filter surface of the wheel electronics must not be scratched off. Dirt must be removed using a lint-free cloth. Do not apply tyre mounting paste on the wheel electronics. All traces of tyre mounting paste must be removed from the wheel electronics. 
• During fitting, ensure that the tyre bead is not pressed against the wheel electronics unit. 
• Huge tension can be transferred to the tyre bead when the mounting paste dries quickly. It is therefore absolutely essential to mount the upper and lower tyre bead quickly and without delay. 

1. Complete preparatory steps for mounting tyres: 
   • Remove abraded rubber particles from the disc wheel and check for damage.

     > 441202 CHECKING DISC WHEELS

   • Fit and clamp the clean wheel as described in the operating instructions provided for the tyre removal/mounting machine.
   • On vehicles with TPM, check the valve and wheel electronics unit for damage. Replace these components if they are damaged or if they do not comply with specifications (special information on TPM).
   • Always replace the rubber valve (on vehicles without TPM). Use a commercially available insertion tool and tyre mounting paste.
   • If you intend to continue using the tyre, check it for damage (sealing face between tyre/rim, ply breakage, tyre beads, sidewalls and tread depth).
   • As a general rule, check the bead area (mounting and sealing face) for damage before mounting tyres (even new tyres). Ensure that this area is perfectly clean to prevent any slow air leaks (loss of tyre pressure) in this area (after mounting the tyre). A loss of tyre pressure often goes unnoticed on vehicles without TPM. Serious consequence: Reduced driving dynamics and the tyre can be damaged irreparably as a result of increased kneading action (overheating). 
2. Coat the rim and tyre (both bead areas) with a sufficient amount of tyre mounting paste TIP TOP Universal, Order No. 593 0601 or Contifix.  Absolute cleanliness is essential (clean brush/clean tyre mounting paste). Make sure that there are no traces of tyre mounting paste on the wheel electronics unit.
3. Fitting lower tyre bead (first tyre bead). 

   Place the tyre at the correct position on the disc wheel (check direction of rotation or inside/outside position).

   Push in mounting arm and position on top of the rim flange. The mounting head must be offset by 180° with respect to the valve.

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.

   Mounting tyre, lower bead, Figure 1

   Push the lower tyre bead (first tyre bead) partly over the rim flange and guide it through the mounting head > Mounting tyre, lower tyre bead, Figure 2  . Turn the disc wheel slowly in a clockwise direction (clockwise rotation of mounting table) until the lower tyre bead is completely fitted.

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.

   Mounting tyre, lower tyre bead, Figure 2

   Information 

   • A bead depressor must be used for mounting the upper tyre bead (second tyre bead). 
   • There are two types of bead depressors. These are described in information 4.1 and 4.2 below. 
   • The Wulstboy bead depressor (type 2 in information 4.2) must be used for tyre/wheel combinations that are more difficult to mount. 
4. Fitting upper tyre bead (second tyre bead) using bead holding-down device. This presses the tyre bead into the well base. 
   1. 4.1 Fitting upper tyre bead (second tyre bead) using bead holding-down device type 1 = special tool 9539 

      Courtesy of PORSCHE CARS NORTH AMERICA, INC.

      Mounting tyre, upper bead using holding-down device 9539

      Position the mounting head -1-  approx. 15 cm to he right of the valve -2-  .

      Hold the upper tyre bead (second tyre bead) in the deep bed using the bead holding-down device 9539 and turn the disc wheel slowly at the same time (clockwise rotation of mounting table) until the upper tyre bead is completely fitted.

   2. 4.2 Fitting upper tyre bead (second tyre bead) using bead holding-down device type 2 = Wulstboy 

      Courtesy of PORSCHE CARS NORTH AMERICA, INC.

      Inserting Wulstboy blocks

      Position the mounting head approx. 15 cm to the right of the valve.

      Use the upper plastic press-off roller (on the mounting machine) to press the upper tyre bead approx. 4 to 5 cm below the rim flange (max. 5 cm/the belt edge of the tyre must not be deformed by the plastic press-off roller). This makes space for the bead depressor blocks.

      Fit the bead holding-down device (Wulstboy) into the middle of the "wheel/rotary plate" -1-  . Move the arm -2-  of the bead holding-down device to the 1 O'clock position.

      Turn the wheel slowly in a clockwise direction (clockwise rotation) and insert the blocks -3-  of the bead holding-down device.

      Continue turning the disc wheel slowly (clockwise rotation) until the upper bead is completely fitted.

      After fitting the upper tyre bead, loosen the bead holding-down device by turning the disc wheel anticlockwise (anti-clockwise rotation) and remove the blocks using the upper press-off roller.

   WARNING: High tyre seating pressure 

   • Risk of squashing or bruising 
     1. → Use a tyre filling cage.
5. Filling/setting tyres. 
   1. 5.1  Remove entire wheel from tyre fitting unit.
   2. 5.2  Fill the tyre (without the valve insert) with air immediately in the tyre filling cage  (while the tyre mounting paste is still fully effective). Continue filling the tyre until the tyre beads slide/jump over the humps (max. 3.3 bar/48 psi).

      Courtesy of PORSCHE CARS NORTH AMERICA, INC.

      Tyre filling cage

      If the tyre is not seated correctly when the maximum permitted tyre seating pressure (max. 3.3 bar/48 psi) is applied, coat the wheel and tyre again with tyre mounting paste TIP TOP Universal or Contifix and repeat the procedure.

   3. 5.3  Screw in new valve insert. Counter at the valve body when tightening. Required tightening torque is 0.2 Nm/0.1 ftlb to 0.35 Nm/0.2 ftlb. (20 to 35 Ncm/1.6 to 3 inlb.). A safety valve screw-on tool with tightening control (e.g. from Butler) is ideal for this.

      Fill tyre to the setting pressure of 4.0 bar (58 psi). Check that the tyre bead is seated correctly. The tyre must be lying evenly against the rim all the way around.

      Set the prescribed tyre pressure.

      > 4405IN Wheels and tyres/tyre pressure 

      > 4405IN Wheels and tyres/tyre pressure 

      Screw on valve cap.

6. Balance the wheel 

   > WM, 440593 BALANCING WHEEL 

7. Perform a test drive.  Avoid extreme driving manoeuvres (acceleration, braking) during the test drive to prevent the tyre from turning on the rim.

   This can happen if the tyre mounting paste is not completely dry. Optimum balancing will be impaired as a result.

   Observe the following criteria during the test drive:

   1. 7.1  TPM function (Tyre Pressure Monitoring system).

      Before starting the test drive (with "ignition on"), select the mounted set of wheels under Main menu > TPM > Settings in the instrument cluster. The control unit then learns the wheel positions again while the vehicle is driving.

      The system starts learning as soon as you accelerate above 25 km/h (16 mph). The learning time is normally about 30 seconds, but can take several minutes when the vehicle is driven in a metallic environment (e.g. multi-storey car park, bridge and other concrete, highly metallic surfaces).

   2. 7.2  Rough running performance and vibrations
   3. 7.3  Vehicle handling.