Where there is a tightening sequence specified in this Service Manual, the bolts, nuts, or screws must be tightened in the order and by the method indicated.
Torque wrench setting figures given in this manual must be observed. The torque tools used must be of accurate calibration.
|0 Nm to 25 Nm
|26 Nm to 100 Nm
|101 Nm to 200 Nm
Locking devices, where specified, must be fitted. If the efficiency of a locking device is impaired during removal it must be renewed. This applies particularly to micro-encapsulated fixings which must always be replaced if disturbed. Where necessary, the text in this manual will indicate where such a fixing is used.
Use of crow foot spanner adapters with torque wrenches
The use of a crow foot spanner adapter will effectively lengthen the lever arm of a torque wrench. The amount of torque applied to a fastener is increased as the torque wrench lever arm is extended, therefore the torque wrench setting must be adjusted in order to achieve the correct tightening torque.
Before tightening a fixing using a crow foot spanner adapter, measure the normal length of the torque wrench from the centre of the drive square to the centre of the handle (dimension L1). Fit the crow foot spanner adapter to the torque wrench as shown below. Measure the extended length of the torque wrench from the centre of the crow foot spanner head to the centre of the handle (dimension L2).
Use the following formula to calculate the correct torque wrench setting to achieve the required tightening torque.
Note: The example shown below is calculated using a crow foot spanner measuring 25 mm from the centre of the spanner head to the centre of the drive square.
|M1 = M2 x L1 / L2
|M2 is the required tightening torque to be applied
|L1 is the normal length of the torque wrench, measured from the centre of the drive square to the centre of the handle
|L2 is the extended length of the torque wrench, measured from the centre of the crow foot spanner head to the centre of the handle
|M1 is the calculated torque wrench setting