Piston And Cylinder Bore, Checking

WARNING: This page is about a different car, the 2023 Volkswagen Arteon. However, it is still accessible from the selected car via links, so may be relevant.

Special tools and workshop equipment required

Cylinder Dial Bore Gauge:VAS 6078

Pistons, Checking

-- Using a commercially available outside micrometer, measure 10 mm from the lower edge and at a 90° offset to the piston pin axis.

Fig 1: Checking Piston Bore

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

Refer to Check and Adjustment Values .

Cylinder Bore, Measuring

CAUTION:

Risk of damage to the cylinder bore by improper handling.

- Never work on the cylinder bore with service equipment, for example drill open, honing or sanding.

-- Using a Cylinder Dial Bore Gauge:VAS 6078 measure in a diagonal sequence at three positions -c- transversely -a- and longitudinally -b-.

Fig 2: Cylinder Bore, Checking

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

Requirement

The measurement must not be performed, when the cylinder block is secured to the Engine and Gearbox Bracket:VAS 6095A .

Refer to Check and Adjustment Values .

Piston Ring Gap, Measuring

-- Insert the piston ring from above, up to 15 mm from the edge of the cylinder of the lower cylinder opening.

Fig 3: Checking Piston Ring Gap

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Check the piston ring gap with a commercially available feeler gauge.

Refer to Check and Adjustment Values .

Piston Ring Height Clearance, Measuring

-- Clean the piston ring groove.

Fig 4: Checking Piston Ring Groove Clearance

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Insert the piston ring into the ring groove and check the piston ring height clearance with a commercially available feeler gauge.

Refer to Check and Adjustment Values .