SEAT Workshop Service and Repair Manuals > Leon Mk1 > Power unit | 4-cylinder diesel engine (2.0 l 4V, TDI Common-Rail) | Enginecrankshaft group, pistons | Dismantling and assembling pistons and conrods

Checking piston position at TDC

t	Test sequence → Anchor

t	Identification of cylinder head gasket → Anchor

Consult the equivalence table for tools and equipment according to applicability among Seat / VW / Audi / Skoda → Chapter.

Special tools and workshop equipment required

t	Adjustment tool -VW 382/7-, please see Correspondence → Anchor

t	Adjustment tool -VW 385/17-, please see Correspondence → Anchor

t	Gauge -VAS 6079-, see equivalent → Anchor

Test sequence

–	Secure the dial gauge -VAS 6079- with Measuring equipment -VW 382/7- and the Measuring equipment -VW 385/17- to the cylinder block as shown in the illustration.

–	Measure the measurement of the individual pistons at different positions and the positions marked with arrows -arrows- (as viewed in the longitudinal direction of the engine: front and rear on the piston).

When fitting new pistons or engine from the spare parts catalogue, the projection measurement of the piston at TDC must be measured.

Install the appropriate cylinder head gasket depending upon piston projection, according to following table:

Piston projection on the upper edge of the engine block	Identification (No. of holes)
0.91 … 1.00 mm	1
1.01 … 1.10 mm	2
1.11 … 1.20 mm	3

Identification of cylinder head gasket

t	Part No. = -Arrow 1-

t	Holes = -Arrow 2-

t	Production code = -Arrow 3- (can be disregarded)

Note

If different values are measured for the protrusion of pistons then the largest measurement is used.

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