Loosen the water pump mounting bolts.
Loosen the tension of the camshaft drive belt by turning the water pump housing.
Remove the camshaft timing pulley.
Press out the camshaft oil seal using a special puller (see photo).
Press in a new camshaft oil seal using mandrel 10 203.
Details of the valve timing mechanism: 1 — camshaft; 2 — valve clearance adjusting bolt; 3 - retaining spring; 4 - lever; 5 - crackers; 6 — spring plate; 7 - valve spring; 8 - oil deflector cap; 9 — valve spring support washer; 10 — cylinder head; 11 — inlet valve; 12 - exhaust valve; 13 — toothed pulley of the camshaft; 14 - rear toothed belt cover; 15 - technological plug; 16 - toothed belt; 17 - Front timing belt cover.
(This publication is borrowed from the resource: AUDIMANUAL)