Operation CHARM: Car repair manuals for everyone.

Cylinder Block Assembly: Testing and Inspection






Piston and Cylinder Bore, Checking

Pistons, Checking





- Measure approximately 15 mm from the lower edge at a 90° angle to the piston pin axis using a 75 to 100 mm external micrometer.

Deviation from nominal size: max. 0.04 mm.






Piston Ring Gap, Checking





- Push piston ring squarely from above down to approximately 15 mm from bottom end of cylinder. To do this use a piston without rings.






Piston Ring Groove Clearance, Checking





- Clean the ring groove of piston before checking.






Cylinder Bore, Checking





Special tools, testers and auxiliary items required

Internal Dial Gauge (VAS 6078) or

Inside Micrometer Set 18-100 mm (US1033/S)

Engine and Transmission Holder (VAS 6095)

Do not bore, hone, grind or rework the cylinder bores with workshop tools. Reworking damages the surface of the cylinder bore.

- Using a (VAS 6078) or (US1033/S) measure in a diagonal sequence at 3 positions transversely - A - and longitudinally - B -.

Deviation from nominal size: max. 0.08 mm.






Measurement of cylinder bore may not be performed when the cylinder block is mounted in (VAS 6095) , false measurements are possible.