Replacement: Replacing all pistons
NOTE:
TECHNICAL INFORMATION
Wear safety goggles.
Wear safety goggles.
NOTE:
The description is for one component only. The procedure is identical for all further components.
- Use the special tools 2 455 002, 2 410 685 and 2 447 297 to remove the piston from the connecting rod.
CAUTION:
Piston pin circlip with preload.
Injury hazard!
Injury hazard!
- The use of the specified special tool for the disassembly or installation is mandatory.
- Wear safety goggles.
- Use the special tool 2 447 297 to remove the piston pin circlip.
- Insert the flat side (3) of the special tool 2 447 297 in the groove (4).
- Use the curved side (2) to grip and remove the piston pin circlip (1).
Check
NOTE:
TECHNICAL INFORMATION
Piston and piston pin are matched to each other.
Always install piston and piston pin together and do not switch by mistake.
Piston and piston pin are matched to each other.
Always install piston and piston pin together and do not switch by mistake.
- Check whether the piston pin (1) has noticeable play in the piston.
Check whether the piston pin (1) can be removed without excessive force.
Result
» The piston pin (1) can only be removed with difficulty or the piston pin (1) has noticeable play.
Measure
- Replace the piston (2) and the piston pin (1).
Parts : Piston, piston pin
- To replace the piston, the piston pin length must be determined.
| Engine | Piston pin length | Pistons |
|---|---|---|
| B38M1 ECE | 12x55 mm | 8 678 931 |
| B38M1 ECE | 12.5X55 mm | 8 678 931 |
| B38M1 ECE | 12X51 mm | 9 494 399 |
| B48M1 ECE | 12x55 mm | 8 678 931 |
| B48M1 ECE | 12.5X55 mm | 8 678 931 |
| B48M1 ECE | 12X51 mm | 9 494 399 |
| B38M1 CN | 12X55 mm | 8 678 931 |
| B38M1 CN | 12.5X55 mm | 8 678 931 |
| B38M1 CN | 12X52 mm | 8 681 079 |
| B48M1 CN | 12X55 mm | 8 678 931 |
| B48M1 CN | 12.5X55 mm | 8 678 931 |
| B48M1 CN | 12X52 mm | 8 681 079 |
| B48O1 ECE+CN | 12X55 mm | 8 678 934 |
| B48O1 ECE+CN | 12.5X55 mm | 8 678 934 |
| B48T1 ECE+CN | 12.5X59 mm | 9 488 343 |
NOTE:
TECHNICAL INFORMATION
Piston and piston pin are matched to each other.
Always install piston and piston pin together and do not switch by mistake.
Piston and piston pin are matched to each other.
Always install piston and piston pin together and do not switch by mistake.
- Install new piston pins (1) in the new piston (2) and the connecting rod (3).
CAUTION:
Piston pin circlip with preload.
Injury hazard!
Injury hazard!
- The use of the specified special tool for the disassembly or installation is mandatory.
- Wear safety goggles.
- Position the piston pin circlip (1).
The opening (mark) of the piston pin circlip must point towards the piston crown (2).
- Preload the piston pin circlip (1) with your thumb.
- Press the piston pin circlip simultaneously with the special tools 2 410 685 and 2 455 002 in the piston.
- Add the special tool 2 410 685
in a rotating manner and press the piston pin circlip completely into the piston.
- Check whether the piston pin circlip (1) fits correctly in the groove (2).
- Check whether the opening (mark) of the piston pin circlip points towards the piston crown (3).







