Volkswagen Workshop Service and Repair Manuals

Pistons and rods - disasemble and assemble

1 -	Segment rings

q	Displace opening in 120 °

q	Remove and install with ring plier

q	Reference “TOP” turned to piston head

q	Check opening between points → Fig.

q	Check ring play on piston groove → Fig.

2 -

Piston

q	With combustion chamber

q	Mark assembly position and correspondence to cylinder

q	Piston/cylinder installation position → Fig.

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

q	Install rings

q	Replace piston in case it is cracked

q	Check piston position on upper part → Chapter.

3 -	Piston pin

q	In case of blocking, heat piston to 60°C

q	Remove and Drift -VW 222A-

4 -

Block

5 -

Rod

q	Mark position to cylinder -A-

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

q	Replace only in sets

6 -

Caps

q	Pay attention to installation position

q	Pay attention to finishing: upper cap (towards piston) made of a more wear-resistant material Identification characteristic: black lining on sliding surface, in separation area

q	Do not invert caps used

q	Place caps centralized

q	Ensure proper seating on retaining slots

q	Axial play wear limit: 0.37 mm

q	Measure radial play with “Plastigage”: wear limit: 0.08 mm Do not turn crankshaft during measurement of radial play

7 -	Engine block

q	Check cylinder diameter → Fig.

q	Piston and cylinder measurement → Chapter.

8 -

Rod cap

q	Pay attention to installation position

q	Due to separation process (breaking) of rods, cap only seats in one position and matches only the pertaining rod

9 -	Oil ejector

q	For piston cooling

10 -

25 Nm

q	Install without sealing

11 -	Rod screw 30 Nm +90 °

q

Replace

q	Lubrificate thread and support surface

q	Measure radial play with a used screw

Piston ring - check openings between points Special tools and workshop equipment required t  Razor calipers Checking sequence –  Insert ring across and over until cylinder lower opening, 15 mm from cylinder shoulder

Piston ring Measures in mm	New	Wear limit
1. Compression ring	0,20...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 play on piston groove Special tools and workshop equipment required t  Razor calipers Checking sequence –  Clean piston groove before moving to checking.

Piston 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 diameter Special tools and workshop equipment required t  Hole/port gage 50...100 mm Checking sequence –  Measure at 3 different locations, in cross and in transversal -A- and longitudinal -B- direction.Deviation regarding nominal measure max. 0.10 mm.   Note Cylinder diameter measurement must not be performed with Engine and gearbox support -VW 540-, as it may cause measurement errors.

Piston-Cylinder/piston installation position Cylinders 1 and 2 piston: Admission valve big seat to wheel side-arrows- Cylinders 3 and 4 piston: Valve big seat for admission valve for belt pulley side-arrows-   Note t  In new pistons correspondence to cylinder is color stamped on piston head. t  Cylinder 1 and 2 piston: Marking 1/2 t  Cylinder 3 and 4 piston: Marking 3/4