Piston: Testing and Inspection
Piston Projection, Measuring at TDC
• Check the piston projection at Top Dead Center (TDC) whenever installing a new piston or new part of the engine. Depending on the piston projection, install the corresponding cylinder head gasket according to the following table.
• If varying values occur when measuring the projection, use the gasket for the largest value.
• The cylinder head gasket must be determined for each cylinder bank removed.
Special tools, testers and auxiliary items required
• Measuring Bar (VW 382/7) from Special Socket and Measuring Tools (VW 382)
• Magnetic Plate 50 mm Dia. (VW 385/17) from Universal Measuring Tool (VW 385)
• Dial Gauge 0-10 mm (VAS 6079)
Procedure
- Attach the (VAS 6079) with measuring bar (VW 382/7) and the (VW 385/17) to the cylinder block.
- Measure the projection on each piston at both spots identified with - arrows - (at the front and back of the piston).
Cylinder Head Seal Identification
1. Holes
2. Part number:
• The cylinder head gaskets for the left and right cylinder head cannot be interchanged because they each have a different shape.