Balance Shaft Module
Balance Shaft Module
--> [ New Balance Shaft Module, Installing ]
--> [ Used Balance Shaft Module, Installing ]
Special tools, testers and auxiliary items required
• Crankshaft stop (T10050) for engines with a round crankshaft toothed belt sprocket
• Locking tool (T10255)
Balance Shaft Module, Removing
- Remove ribbed belt. Refer to --> [ Ribbed Belt ] Ribbed Belt
- Remove belt pulley/vibration damper. Refer to --> [ 29 Belt Pulley/Vibration Damper ] Toothed Belt Drive Assembly Overview.
- Remove lower section of toothed belt guard. Refer to --> [ 25 Lower Toothed Belt Guard ] Toothed Belt Drive Assembly Overview.
- Remove oil pan. Refer to --> [ Oil Pan ] Service and Repair.
- Rotate engine to TDC and secure crankshaft toothed belt sprocket with the crankshaft stop (T10050). Push the crankshaft stop from the front side of the toothed belt sprocket into the teeth. The camshaft toothed segment must be in the "12 o'clock" position.
• The markings on the crankshaft toothed belt sprocket - 2 - and the crankshaft stop (T10050) - 1 - must align. The pin on the crankshaft stop (T10050) must engage in the hole on the sealing flange.
- Remove bolts in sequence - 8 to 1 - and remove balance shaft module with the oil pump.
New Balance Shaft Module, Installing
Conditions
• The crankshaft is secured with the crankshaft stop (T10050).
• The balance shaft module spur gear drive must be installed with the correct backlash.
• A coating is applied to the new intermediate sprocket to achieve the correct backlash.
• If the intermediate sprocket has a white dot, the coating covers only parts of the circumference. If there is no white dot, the entire circumference of the intermediate sprocket is coated.
• The coating wears off in a short period of time and ensure the correct backlash.
• For this reason, a new balance shaft module must always be installed in conjunction with a new intermediate sprocket with coating.
• Only intermediate sprockets with a partial coating have a white dot to indicate the correct installation position.
• There is no installation position to follow for intermediate sprockets with coating on the entire circumference.
• Replace bolts which have been tightened to torque.
CAUTION!
• The intermediate shaft threaded connection must be loosened to position the balance shaft module. When doing so, make sure the bolt is not loosened too much. Otherwise the bearing disc could slip behind the intermediate sprocket.
• Axial bearing disc installation position. Refer to --> [ Axial Bearing Disc Installation Position ] Oil Pump, Oil Pan and Balance Shaft Module
- Before positioning the balance shaft module on the cylinder block, loosen intermediate sprocket bolt - 1 - approximately 45° (1/8 turn).
- Make sure both alignment sleeves for centering the balance shaft module on the cylinder block are present.
- Position balance shaft module on the cylinder block. Make sure the partially coated intermediate sprocket is positioned correctly:
• The white dot - arrow - on the intermediate sprocket must be centered with the crankshaft.
• Make sure the coating on the intermediate sprocket is not damaged.
• Due to the gear ratio, the white dot - arrow - will not be in the original location after rotating the engine.
- Install new bolts in sequence - 1 to 8 - and tighten them by hand.
- Tighten balance shaft module bolts as follows:
- Tighten nuts to 6 Nm in sequence - 1 to 8 -.
- Tight bolts - 5 - and - 7 - to 13 Nm.
- Tighten bolts - 5 - and - 7 - 90° (1/4 turn) using a rigid wrench.
- Tighten bolts - 1 to 4 -, - 6 - and - 8 - to 20 Nm.
- Tighten to bolts - 1 to 4 -, - 6 - and - 8 - an additional 90° (1/ 4) using a rigid wrench.
- Secure balance shaft with locking tool (T10255). Rotate balance shaft if necessary.
• The locking tool pins must engage in the groove on the balance shaft.
- Carefully position balance shaft spur gear on the balance shaft while pressing the intermediate sprocket to the side slightly.
• Make sure the threaded holes on the balance shaft align are centered as much as possible in the slots on the balance shaft spur gear.
• If the slots on the balance shaft spur gear cannot be aligned with the threaded holes in the cover, rotate the spur gear the corresponding number of teeth and position it again.
- Tighten balance shaft spur gear - arrows -.
- Remove locking tool (T10255).
The follow three steps must be performed at the same time (a second technician is required):
- Using a wooden block to assist if necessary, press the intermediate shaft - 3 - forcefully in direction of - arrow - into the splines on the crankshaft spur gear - 2 - and balance shaft spur gear - 1 -.
- Rotate balance shaft spur gear counterclockwise slightly when doing so.
- Tighten new bolt on the intermediate sprocket:
• Tightening specification: --> [ (item 12) 90 Nm plus an additional 90° (/ turn) ] Oil Pump, Oil Pan and Balance Shaft Module.
- Remove crankshaft stop (T10100).
• The intermediate sprocket must not have any angular clearance after installation. This can be checked by pressing slightly with the hand.
The rest of the installation is in reverse order of removal, note the following:
- Install oil pan --> [ Oil Pan ] Service and Repair.
- Install lower section of the toothed belt guard:
• Tightening specification: --> [ (item 27) 10 Nm ] Toothed Belt Drive Assembly Overview.
- Install belt pulley/vibration damper.
• Tightening specification: --> [(item 28)10 Nm plus an additional / turn (90°) ] Toothed Belt Drive Assembly Overview.
- Install ribbed belt. Refer to --> [ Ribbed Belt ] Ribbed Belt.
Used Balance Shaft Module, Installing
Conditions
• The crankshaft is secured with the crankshaft stop (T10050).
CAUTION!
• A new intermediate sprocket with coating must be installed and the hub --> [ 11 Hub ] Oil Pump, Oil Pan and Balance Shaft Module including the bolt --> [ (item 12) 90 Nm plus an additional 90° (/ turn) ] Oil Pump, Oil Pan and Balance Shaft Module and axial bearing discs --> [ (item 13) Axial Bearing Disc ] Oil Pump, Oil Pan and Balance Shaft Module must be replaced if the intermediate shaft bolt was loosened, the crankshaft spur gear was replaced or the crankshaft was removed. Otherwise the backlash will be incorrect.
• Refer to--> [ New Balance Shaft Module, Installing ].
• Proceed as follows if the used balance shaft module will be installed again and if the crankshaft spur gear was replaced or the crankshaft was removed. Do not loosen the intermediate sprocket under any circumstances.
• Replace bolts which have been tightened to torque.
- Secure balance shaft with locking tool (T10255). Rotate balance shaft if necessary.
• The locking tool pins must engage in the groove on the balance shaft.
- Make sure both alignment sleeves for centering the balance shaft module on the cylinder block are present.
- Position balance shaft module on the cylinder block.
• The intermediate shaft must engage in the spur gear on the crankshaft when the balance shaft is secured in place.
• The intermediate sprocket must have slight angular clearance.
- Install new bolts in sequence - 1 to 8 - and tighten them by hand.
- Tighten balance shaft module bolts as follows:
- Tighten nuts to 6 Nm in sequence - 1 to 8 -.
- Tight bolts - 5 - and - 7 - to 13 Nm.
- Tighten bolts - 5 - and - 7 - 90° (1/4 turn) using a rigid wrench.
- Tighten bolts - 1 to 4 -, - 6 - and - 8 - to 20 Nm.
- Tighten to bolts - 1 to 4 -, - 6 - and - 8 - an additional 90° (1/ 4) using a rigid wrench.
- Remove crankshaft stop (T10100).
The rest of installation is in reverse order of removal, note the following:
- Install oil pan. Refer to --> [ Oil Pan ] Service and Repair.
- Install lower section of the toothed belt guard:
• Tightening specification: --> [ (item 27) 10 Nm ] Toothed Belt Drive Assembly Overview.
- Install belt pulley/vibration damper.
• Tightening specification: --> [(item 28)10 Nm plus an additional / turn (90°) ] Toothed Belt Drive Assembly Overview.
- Install ribbed belt. Refer to --> [ Ribbed Belt ] Ribbed Belt.