Assign crankshaft bearing shells - AR03.20-P-4360-01MM

ENGINE 152, 157, 176, 177, 178, 276, 278 

ENGINE 157 

Assignment of the upper crankshaft bearing shells (50), shown on engine 276 

One must ensure the highest levels of cleanliness for all components and toolings for the work to be done.

Soiling can lead to engine damage.

1. Read off assignment numbers.

   The assignment numbers are attached to the cylinder crankcase (see small arrows in Fig 1).

2. Assign the upper crankshaft bearing shells (50) to the respective numbers.

   The assignment takes place based on the number definition.

   The colored marking is located, analog to the lower crankshaft bearing shell (40) (see arrow in Fig 1), at the side on the upper crankshaft bearing shell (50).

   Fig 1: Upper Crankshaft Bearing Shells Assignment Marks - Shown On Engine 276

   Courtesy of MERCEDES-BENZ USA

   Shown on engine 278 

   Fig 2: Upper Crankshaft Bearing Shells Assignment Marks - Shown On Engine 278

   Courtesy of MERCEDES-BENZ USA

   Example, on engine 276 

   • A yellow marked upper crankshaft bearing shell (50) is assigned to the first crankshaft bearing according to the number (here a 2).

   Numbers definition 

   • The number 1 represents the color marking blue.
   • The number 2 represents the color marking yellow.
   • The number 3 represents the color marking red.

   Assignment of the lower crankshaft bearing shells (40) 

   The assignment letters on the front crankshaft journal according to the starting letter of the color marking on the crankshaft bearing shell in the German language.

   Therefore one should ensure correct assignment on the basis of the letter definition.

3. Read off assignment letters.

   The assignment letters are attached in the cylinder sequence on the front crankshaft journal.

4. Assign the lower crankshaft bearing shells (40) to the respective letters.

   The colored marking is located on the edge of the lower crankshaft bearing shells (40) (see arrow in Fig 3).

   Fig 3: Lower Crankshaft Bearing Shells Assignment Marks - Shown On Engine 276

   Courtesy of MERCEDES-BENZ USA

   Example, on engine 276 

   • A white marked lower crankshaft bearing shell (40) must be assigned to the first crankshaft bearing cap (1) according to the first letters (W)

   Letters definition 

   • The letter B represents the color marking blue.
   • The letter G represents the color marking yellow.
   • The letter R represents the color marking red.
   • The letter W represents the color marking white.
   • The letter V represents the color marking violet.

   Install upper and lower crankshaft bearing shells (40, 50) 

5. Wet upper crankshaft bearing shells (50) with engine oil.
6. Insert upper crankshaft bearing shells (50) in the respective crankshaft bearing.

   Ensure that the anti-twist locks (50a) of the upper crankshaft bearing shells (50) are seated in the notches (50b) of the cylinder crankcase.

7. Wet lower crankshaft bearing shells (40) with engine oil.
8. Insert lower crankshaft bearing shells (40) into the respective crankshaft bearing caps (10).

   Ensure that the anti-twist locks (40a) of the lower crankshaft bearing shells (40) are seated correctly in the notches (40b) of the crankshaft bearing cap (10).

   Fig 4: Installing Upper And Lower Crankshaft Bearing Shells

   Courtesy of MERCEDES-BENZ USA

   Use of the upper and lower thrust plate 

9. Wet crankshaft bearing journal with engine oil.
10. Insert crankshaft in crankcase.
11. Wet upper thrust plates (B) with engine oil.
12. Mount upper thrust plates (B) on crankshaft main bearing.

    The oil grooves on the upper thrust plates (B) must point to the crank webs.

13. Wet lower thrust plates (A) with engine oil.
14. Mount lower thrust plates (A) together with the crankshaft fitted bearing cap.

    The oil grooves (a) on the lower thrust plates (A) must point to the crank webs.

    The anti-twist locks on the lower thrust plates (A) must sit in the slots (x) on the crankshaft main bearing cap.

15. Insert crankshaft bearing cap (10).
    Fig 5: Anti-Twist Locks Slots On Lower Thrust Plates

    Courtesy of MERCEDES-BENZ USA