Fitting pistons (in situ)
- Assemble piston and connecting rod by driving in the gudgeon pin, using a plastic mallet and drift. Make sure that the mark on the piston crown faces the timing cover and that the numbers on the connecting rods face the exhaust side.IMPORTANT: If one connecting rod is to be changed to a newer type (part no. 91 97 617), all the connecting rods must be changed or the difference in weight will become too great.
- Fit the gudgeon pin lock ring.WARNING: It is extremely important to fit the lock ring with its opening upwards.
- Place the bearing halves in place in the connecting rods.
- Fit PROTECTIVE COLLARS 75 19 531 over the connecting rod studs and oil the piston rings, bearings and cylinder.
- Fit the piston using piston fitting tool 78 62 287
.
IMPORTANT: Pistons of different makes must not be used in the same engine. The name of the manufacturer is cast inside the piston.
- Fit the big-end bearing caps with bearing halves (connecting rod numbers facing in the same direction).
Tightening torque, with nut 20 Nm +70° (15 lbf ft +70°)
Tightening torque, with bolt 25 Nm +100° (18 lbf ft +100°)
- Fit the subframe and oil sump, see OIL SUMP (IN CAR) .
- Place a WEDGE 83 95 238 between the subframe and oil sump and remove the lifting beam.