Piston and Cylinder

Piston and cylinder





Checking piston ring gap

Special tools, testers and auxiliary items required
^ Feeler gauge

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








Checking ring to groove clearance

Special tools, testers and auxiliary items required
^ Feeler gauge

- Clean ring grooves before checking.








Checking cylinder bores

Special tools, testers and auxiliary items required
^ 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. 0.10 mm

Note: Measurement of the cylinder bore must not be performed when the cylinder block is mounted in engine and transmission holder VAS 6095. The result of doing so would be false measurements.





Installed position of piston and piston/cylinder allocation
Pistons in cylinder 1 and 2:

Large valve pocket for intake valve toward flywheel side - arrows -

Pistons in cylinder 3 and 4:

Large valve pocket for intake valve toward belt pulley side - arrows -

Note:
^ On new pistons, the cylinder allocation is stamped on the piston face in paint.
^ Pistons for cylinder 1 and 2: identification 1/2
^ Pistons for cylinder 3 and 4: identification 3/4