Oil Pump: Service and Repair

Oil Pump with Balance Shaft Drive

=> [ Chain Tensioner, Pretensioning ]

Special tools, testers and auxiliary items required

• Connecting Pin (T10027)

• Silicone Sealant (D 176 404 A2)

Removing

- Remove the oil pan. Refer to => [ Oil Pan ] Service and Repair.

- Remove the chain guard. Disengage the locking lugs through the openings - arrows - if necessary using a small screwdriver.






- Rotate the crankshaft to set cylinder 1 at Top Dead Center (TDC).






• Make sure there is a mark on the balance shaft chain sprocket opposite the securing hole - arrow -. Mark the position with a waterproof marker if the mark is missing. The mark will be needed later when installing.






- Loosen the oil pump chain sprocket bolt. Counter hold the center bolt for the vibration damper.







The chain sprocket driving the balance shafts must not be loosened!

- Release the tension on the chain rail using a screwdriver - arrow - and secure it using a 3 mm hex wrench - 1 -, across flats.






- Remove the oil pump chain sprocket and disengage the chain from the balance shaft drive.






- Loosen the balance shaft drive bolts working from the outside toward the inside and remove it. Oil pump with balance shaft drive overview. Refer to => [ Oil Pump with Balance Shaft Drive ] Service and Repair.






Installing and Adjusting

• Chain tensioner is pre-loaded. Refer to => [ Chain Tensioner, Pretensioning ].

- Place the intermediate plate as shown onto the alignment bushings - arrows - in the balance shaft drive.






- Install the oil pump with balance shaft drive and intermediate plate. Tighten the bolts working from the inside toward outside to 15 Nm + 90° (1/4) additional turn.






• Note the different length of the bolts. Refer to => [ Balance Shaft Drive Bolt Allocation ].

- Rotate the crankshaft to set cylinder 1 to TDC.






- Set the mark on the balance shaft chain sprocket - arrow - opposite the alignment bore.






- Secure the chain sprocket in this position using the connecting pin (T10027). Place the chain onto the balance shaft chain sprocket.






- Install the oil pump chain sprocket and tighten the bolt by hand.

• The oil pump chain sprocket fits only in one position. To install, only the oil pump must be turned.

- Remove the connecting pin (T10027) and 3 mm hex wrench - 1 -. Secure the oil pump chain sprocket. Tightening specification: 20 Nm + 90° (1/4) additional turn. Counter hold the vibration damper center bolt.






- Install the oil pan. Refer to => [ Oil Pan ] Service and Repair.

Further installation is in the reverse order of removal.

Balance Shaft Drive Bolt Allocation





A M7 x 40 hex collar bolt
B M7 x 70 hex collar bolt
C M7 x 90 hex collar bolt
D M7x 55 hex collar bolt
E Sealing plug with O-ring

Chain Tensioner, Pretensioning

- Pretension the piston by hand - arrow -.






- Push the chain rail in the - direction of the arrow - and secure it with a 3 mm hex wrench - 1 -.