Golf Mk4
| Dismantling and assembling pistons and conrods |
| 1 - | Piston rings |
| q | Offset gaps by 120°. |
| q | Remove and install using piston ring pliers. |
| q | “TOP” faces towards piston crown. |
| q | Checking ring gap → Fig.. |
| q | Checking ring-to-groove clearance → Fig.. |
| q | 2 or 3 part oil scraper ring, mixed installation permitted. |
| 2 - | Piston |
| q | Checking → Fig.. |
| q | Mark installation position and cylinder number. |
| q | Arrow on piston crown points to pulley end. |
| q | Install using piston ring clamp. |
| 3 - | Conrod |
| q | Renew as set only. |
| q | Mark cylinder number -B-. |
| q | Installation position: Marking -A- faces towards pulley end. |
| 4 - | Conrod bearing cap |
| q | Note installation position. |
| 5 - | 30 Nm + 1/4 turn (90°) further |
| q | Alternative: Bolt only. |
| q | Oil threads and contact surface. |
| q | To measure radial clearance, tighten to 30 Nm but not further. |
| 6 - | Pressure relief valve, 27 Nm |
| q | Opening pressure: 1.3...1.6 bar. |
| 7 - | Oil spray jet |
| q | For piston cooling |
| 8 - | Bearing shell |
| q | Note installation position. |
| q | Do not interchange used bearing shells. |
| q | Ensure retaining lug fits tightly in recess |
| q | Axial clearance new: 0.05...0.31 mm, wear limit 0.37 mm. |
| q | Check radial clearance with Plastigage: new: 0.01...0.06 mm, wear limit: 0.12 mm. Do not rotate crankshaft when checking radial clearance. |
| 9 - | Cylinder block |
| q | Checking cylinder bores → Fig.. |
| q | Piston and cylinder dimensions → Chapter. |
| 10 - | Conrod bolt |
| 11 - | Circlip |
| 12 - | Piston pin |
| q | If difficult to remove, heat piston to 60° C. |
| q | Remove and install with drift -VW 222 A-. |
