Volkswagen Workshop Service and Repair Manuals

Pistons and rods - disassemble and assemble

1 -	Guide rings

q	Displace opening 120°

q	Remove and install with ring plier

q	Reference “TOP” turned to piston head

q	Check intergate openings → Fig.

q	Check ring space on piston channel → Fig.

2 -

Piston

q	With combustion chamber

q	Mark installation position and cylinder correspondence

q	Piston/cylinder installation position → Fig.

q	-Arrow- on piston head points to belt pulley side

q	Install with ring tension belt

q	If piston is cracked, replace it

q	Check piston position on upper part → Chapter.

3 -	Piston pin

q	If piston is locked, heat at 60 °C

q	Remove and install with Drift -VW 222A-

4 -

Lock

5 -

Rod

q	Replace only set

q	Mark cylinder position -A-

q	Installation position: Markings -B- point to belt pulley side

6 -	Adjusting pin

q	Adjusting pin must be firmly positioned on rod

7 -

Cap

q	Mind installation position

q	Do not change used caps position

q	Mind proper seating on retaining protuberances

q	Axial space wear limit: 0.37 mm.

q	Measure radial space with “Plastigage”: wear limit: 0.08 mm. During radial space measurement, do not move crankshaft

8 -	Engine block

q	Check cylinder diameter → Fig.

q	Piston and cylinder measures → Chapter.

9 -

Rod cover

q	Mind installation position

10 -	Oil ejector

q	For piston cooling

11 -

25 Nm

q	Install without seal

12 -	Rod screw, 30 Nm + 90

q

Replace

q	Oil thread and support surface

q	For radial space measurement, use used screw

Piston ring - check interpoint openings Special tools and workshop equipment required t  Razor gauge Checking sequence –  Introduce ring, perpendicularly and from top, until cylinder lower opening, at around 15 mm from cylinder shoulder.

Segment ring measures in mm	new	Wear limit
1. Compression ring	0.25...0.40	1.0
2. Compression ring	0.20...0.40	1.0
Oil scraper ring	0.25...0.50	1.0

Piston ring - check ring space in piston channel Special tools and workshop equipment required t  Razor gauge Checking sequence Clean piston groove before checking.

Segment ring measures in mm	new	Wear limit
1. Compression ring	0.06...0.09	0.25
2. Compression ring	0.05...0.08	0.25
Oil scraper ring	0.03...0.06	0.15

Check cylinder bore Special tools and workshop equipment required t  Internal micrometer 50...100 mm Checking sequence –  Measure in 3 different points, in cross, and in transversal and longitudinal -A- direction -B-. Deviation from nominal measure máx. 0,10 mm   Note Cylinder bore measurement must not be made with engine block fixed on assembly anvil with Engine and gearbox support -VW 540-, once measurement mistakes may be registered.

Piston - Piston/cylinder installation position Piston in cylinders 1 and 2: Valve large seat for intake valve to the steering wheel side-arrows- Piston in cylinder 3 and 4: Valve large seat for intake valve to the belt pulley side-arrows-   Note t  In new pistons cylinder position is marked in colours on piston head. t  Piston for cylinder 1 and 2: Marking 1/2 t  Piston for cylinder 3 and 4: Marking 3/4