11 21 531 Replacing all main crankshaft bearing shells (N63): Notes
Special tools required:
- 00 2 590
- 00 9 120
- 11 6 251
- 11 6 252
See MAINTENANCE AND GENERAL INFORMATION - SPECIAL TOOLS .
See ENGINE - SPECIAL TOOLS (N54, N63) .
Necessary preliminary tasks:
- Remove crankshaft
Observe crankshaft construction stage:
S: Series
B: Repair stage 1
C: Repair stage 2
The letters denote the bearing shell classification for the relevant bearing position from 1 to 5 (main bearing cap).
The first letter on the left applies to the first bearing position at the front on the timing chain drive.
Color coding on crankshaft 1 to 5
Y= yellow
G= green
V= violet
The letters denote the bearing shell classification for the relevant bearing position from 1 to 5 in the crankcase and is located on the transmission side in the Vee. The first letter on the left applies to the first bearing position at the front on the timing chain drive.
Color coding in crankcase 1 to 5.
Y= yellow
G= green
V= violet
Installation:
Install main bearing shells (1) with lubrication groove in crankcase.
Install main bearing shells (2) without lubrication groove in the main bearing caps.
The letters denote the bearing shell classification for the relevant bearing position from 1 to 5 (main bearing cap).
The first letter on the left applies to the first bearing position at the front on the timing chain drive.
Color assignment on crankshaft 1 to 5
| Code letter | Color code |
|---|---|
| New (A to H) | Yellow |
| Old Y | Yellow |
| New (I to R) | Green |
| Old G | Green |
| New (S is Z) Old V |
Violet |
| Tolerance classes | Bearing shell covers | |
|---|---|---|
| Crankcase | A B C D E G H |
Yellow Yellow |
| Crankcase | I C M N P q R |
Green Green |
| Crankcase | S T U W X Z |
Violet |
Installation note:
Install main bearing shells (1) with lubrication groove in crankcase.
Install main bearing shells (2) without lubrication groove in the main bearing caps.
Turn back thread support bushing into main bearing cap.