Cylinder Block Assembly: Locations

Assembly overview





Conventional connecting rod
1- Piston rings
^ Offset gaps by 120°
^ "TOP" faces towards piston crown
2- Piston
^ Mark installation position and cylinder number
^ Arrow on piston crown points to belt pulley end
^ 2-part oil scraper ring





3- Connecting rod
^ Only replace as a set
^ Mark relation to cylinder -B-
^ Installation position: Marking -A- faces belt pulley end
4- Connecting rod bearing cap
^ Mark relation to cylinder -B-
^ Installation position: Marking -A- faces belt pulley end
5- 30 Nm plus 1/4 turn (90°)
^ Always replace
^ Oil thread and contact surfaces
^ To measure radial clearance tighten to 30 Nm, but do not turn further





6- Bearing shell
^ Observe installation position
^ Do not interchange used bearing shells
^ Ensure retaining lugs fit tightly in recesses.
^ Upper bearing shell with oil drilling for piston pin lubrication.
^ Axial clearance, New: 0.10 to 0.31 mm; Wear limit: 0.37 mm
^ Check radial clearance with Plastigage(R): New: 0.01 to 0.06 mm; Wear limit: 0.12 mm
^ Do not rotate crankshaft when checking radial clearance
7- Cylinder block
8- Connecting rod bolt
9- Circlip
10- Piston pin
^ If difficult to remove, heat piston to 60°C





Industrially cracked connecting rod
1- Piston rings
^ Offset gaps by 120°
^ Manufacturer's mark faces piston crown
2- Piston
^ Mark installation position and cylinder number
^ Arrow on piston crown points to belt pulley end
3- Piston pin
^ If difficult to remove, heat piston to 60°C





4- Circlip
5- Connecting rod
^ With split bearing cap
^ Only replace as a set
^ Mark relation to cylinder -B-
^ Marking -A- faces belt pulley end
6- Bearing shell
^ Observe installation position
^ Do not interchange used bearing shells
^ Check seated securely
^ Axial clearance, New: 0.10 ... 0.35 mm; Wear limit: 0.4 mm
^ Check radial clearance with Plastigage(R): New: 0.01 ... 0.05 mm; Wear limit: 0.09 mm (Do not rotate crankshaft when checking radial clearance)





7- Cylinder block
8- Connecting rod bearing cap
^ Observe installed position
^ Caps only fit in one position and only on appropriate connecting rod due to breaking procedure (industrially cracking) separating cap from connecting rod
9- 30 Nm plus 1/4 turn (90°)
^ Torx(R) E10
^ Replace
^ Oil thread and contact surface
^ To measure radial clearance tighten to 30 Nm, but do not turn further





Fig. 1 Checking piston ring gap

Special tools and equipment
^ Feeler gauge

Work sequence
- Push ring squarely from above down to approx. 15 mm from bottom end of cylinder.








Fig. 2 Checking ring to groove clearance

Special tools and equipment
^ Feeler gauge

Work sequence
- Clean groove before checking.








Fig. 3 Checking piston

Special tools and equipment
^ External micrometer 75 to 100 mm

Work sequence
- Measure pistons approx. 10 mm from lower edge of skirt, 90° offset to axis of piston pin.
Deviation from nominal dimension: max. 0.04 mm





Fig. 4 Installation position of bearing shells
Bearing shell -1- with oil channel (arrow) for connecting rod.
Bearing shell -2- without oil channel connecting rod bearing cap.
- Insert bearing shells and connecting rod bearing cap centrally.
Dimension -a- must be same on both left and right side. Deviation: 0.2 mm.





Fig. 5 Checking cylinder bores

Special tools and equipment
^ Internal dial gauge 50 ... 100 mm
- Measure bores at 3 locations in both directions -A- across engine and -B- in line with crankshaft.
Deviation from nominal dimension: max. 0.08 mm

Note: Measuring of the cylinder bores must not be done when the cylinder block is mounted on a repair stand with adapter bracket VW 540, as incorrect measurements would then be possible.