Note: The presence of metal chips or a large number of small metal particles found during engine repairs may indicate damage to the crankshaft bearings and connecting rods. To prevent further damage from developing, thoroughly clean the oil passages and replace the oil nozzles, oil cooler and oil filter.
1. The installation details of the crankshaft and the connecting rod and piston group are indicated on the resist. illustrations.
42.1a Installation details of the crankshaft
1 Upper main bearing (with oil groove)
2 Crankshaft helical gear, for driving the balancer shaft module and oil pump, replaced with the intermediate gear
3 Lower main bearing (without oil groove)
4 Main bearing thrust washers #3
5 Bolts, to be replaced, 65 Nm, then retighten 90°
6 Main bearing caps, #3 - with washer grooves 4
7 Needle bearing, DSG models only
8 crankshaft
42.1b Parts of the connecting rod and piston group
1 Piston rings, mounted with 120°angle between locks
2 Piston with combustion chamber, arrow on the bottom points towards the timing drive, numbering from the timing side
3 Piston pin, heat up to 60°C for easy installation
4 Retaining ring
5 Connecting rod, replaceable only when paired with cap 8, marked with cylinder affiliation (A) and timing side (IN)
6 Main bearing shells
7 Cylinder block
2. If parts to be removed are to be reused, position them so that they are in the same location and orientation when reinstalled.
3. Replacing the needle bearing on models with DSG is the same as on 3.6L gasoline engines (see Section 14). Install the bearing to a depth of 1.5-1.8 mm.
4. Connecting rod bearing shells, mounted on the side of the connecting rod, are made of a more wear resistant material than the lower shells and are marked with a black line on the working surface in the connection area. Top bearings can be identified by the black markings on the mating surface.
5. Connecting rods and connecting rod bearing caps are chipped, so they should only be replaced together. The marks on the connecting rods and connecting rod bearing caps must be on the same side. Install connecting rod bearing shells in the center (both in the connecting rod and in its cap), so that the distance on both sides is the same. The procedure for breaking off the cover from the new connecting rod is carried out in the same way as described on the 3.6 liter engine (see Section 14).
6. If new pistons are installed or a short cylinder block is used, the number of marking holes in the cylinder head gasket must be determined (see resist. illustration), which depends on the maximum protrusion of all pistons relative to the upper surface of the cylinder block. One hole corresponds to a protrusion of 0.91-1.00mm, two holes to a protrusion of 1.01-1.10mm, and three holes to a protrusion of 1.11-1.20mm.
42.6 Marking of the cylinder head gasket
1 Part number
2 Marking holes
3 Control production code (doesn't matter)