Checking procedure:

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Remove camshaft. See CAMSHAFTS AND CAMSHAFT ADJUSTERS, REMOVING AND INSTALLING .
Remove valve roller lever.
Install camshaft without drive chain and secure with baring caps 2 and 4.
Install dial indicator bracket VW 387 to cylinder head.
Press camshaft by hand against dial indicator.
Zero dial indicator.

Fig 1: Measuring Camshaft Axial (End) Play Using Dial Indicator Bracket VW 387
Courtesy of AUDI OF AMERICA, INC.
Press camshaft away from camshaft.

Read measurement.

CAMSHAFT AXIAL (END) PLAY SPECIFICATIONS

New	Wear limit
0.05-0.15 mm	(0.0020-0.0059 in.)
0.20 mm (0.0079 in.)	(0.0020-0.0059 in.)

Fig 2: Installing Dial Indicator Bracket VW 387 To Cylinder Head

Courtesy of AUDI OF AMERICA, INC.