Operation 5-13 To remove

To check the length of a connecting rod

Operation 4-11

A partially finished small end bush, which can be fitted to the original connecting rod and machined to obtain the correct length grade is available, see Operation 4-14. Specialist equipment and personnel with the correct training are needed to machine the partially finished small end bush. Connecting rod kits are also available with the small end bush fitted and machined to obtain the correct connecting rod grade.

Cautions:

It is important that the piston does not contact the cylinder head. Ensure that the piston height above the cylinder block is correct. Ensure that the connecting rods are fitted in the correct cylinder. Record the position of the connecting rod and its relevant cylinder when it is removed from the engine. To ensure that the piston height above the cylinder block is correct, the engine may have up to six length grades (F to L) of connecting rods fitted. Identification of the length grade is by a letter or colour which is marked on the side of each connecting rod (A1). The letter F is the longest grade of connecting rod and letter L is the shortest grade. The difference between grades is 0,046 mm (0.0018 in). If the grade letter or colour on the side of the connecting rod cannot be seen, the length can be checked by the measurement of the dimension (X) shown in (A). Before the length of the connecting rod is measured, ensure that the bores of the big end and the small end are square and parallel, see Operation 4-13. The length is checked with the big end bearing removed and the original small end bush fitted. The dimensions for each grade are listed in the table below:

Grade letter Colour code Length (mm)

F Red 165,728/165,761 G Orange 165,682/165,715 H White 165,637/165,670 J Green 165,591/165,624 K Purple 165,545/165,578 L Blue 165,499/165,532

A

X 1

G0009