Crank Mechanism, Assembling
Crank mechanism, assembling
Special tools:
951 2767 Roller 951 2767 Roller
999 1801 STANDARD SHAFT 999 1801 Standard Shaft
999 5676 Drift replaced by 9997174 999 5676 Drift Replaced By 9997174
999 5746 Holder 999 5746 Holder
Note! The illustrations in this service information are used for different model years and/or models. Some variation may occur. However, the essential information in the illustrations is always correct.
Note! For tightening torques not in the text, see Tightening torque Tightening Torque.
Cleaning
Ensure that the all components are completely clean.
Blow clean the oil ducts in the block, intermediate section and sump.
Installing the piston cooling valve and nozzles
Install the piston cooling nozzles. Tighten the screws.
Install the piston cooling valve. Use a seal washer. Tighten. See Tightening torque Tightening Torque.
Classification of main bearings
Wipe clean the bearing recesses in the block and the intermediate section.
Check that the components are clean and undamaged.
Check the classification of the block and crankshaft.
The classification marking is at the rear edge of the block and the crankshaft. The classification is read from digit 1 to 7. The first letter after digit 1 is the classification of main bearing 1. The bearing recesses are numbered starting at the front of the engine.
Selecting bearings
Note! Always use new bearings.
Bearing halves with grooves are always installed in the engine block.
Install the main bearings in the cylinder block and the intermediate section. See the table. The axial bearing is positioned at bearing recess 5
1. Classification cylinder block
2. Classification crankshaft
3. cylinder block
4. Intermediate section
Example. The marking on the block at bearing position 1 is B. The marking on the crankshaft at the corresponding bearing position is C. This gives a red marked bearing in the block and a yellow marked bearing in the intermediate section.
Note! The thickest of the bearing halves shall always be installed in the intermediate section. This is to keep the centre line as straight as possible.
Applying liquid gasket
Wipe the surfaces dry. Apply liquid gasket 11 61 059 to the intermediate section.
The surface must be completely covered without any excess. Use roller 951 2767 Roller 951 2767 Roller. Thoroughly lubricate all the bearing shells and the thrust bearing's surface.
Tightening the intermediate section
Install the two old screws for the flywheel and carrier plate at the rear edge of the crankshaft. Lift these and the front of the crankshaft.
Carefully position the crankshaft in the block. The crankshaft must not be turned before the intermediate section has been torque tightened. Position the intermediate section. Lubricate and install all the screws.
Note! Use new M10 bolts.
Caution! The M8-bolts on the exhaust side have two lengths.
Install the intermediate section and the screws on the exhaust side at bearing recesses 2 and 5.
Pull down the intermediate section. Tighten the screws. See Tightening torque Tightening Torque.
Marking the connecting rod (where applicable)
Assemble the connecting rod. Check that the cover is facing the correct direction. Tighten to 20 Nm.
Secure the large end of the connecting rod in a vice with soft jaws (copper or aluminium). Mark both halves with the cylinder number. Use a centre punch or number punch.
Selecting piston
For every cylinder there is a classification letter stamped (C, D, E) on the top of the engine block.
First letter after the digit 1 corresponds to the classification of the cylinder bore in cylinder 1 and is then followed by cyl. 2, 3, 4, 5.
Cylinder selection is determined by the classification of the cylinder bore. For example: Cylinder class D must have pistons marked D etc.
Installing piston rings
Caution! Make sure that the piston rings are not stuck and that they turn easily.
Note! Incorrect positioning may result in higher oil consumption.
Use piston ring pliers. Turn the piston rings so that the openings are offset as illustrated.
A=Compression ring. The text on the piston ring must be upwards.
B=Scraper ring. Chamfered edge must face downwards.
C=Oil ring. Three sections, identical on all sides. First install the expander ring (C), then the two other rings over the expander ring.
Assembling pistons and connecting rods
Warning! The lock ring can easily fly off. Wear protective goggles
There is an arrow marking on the upper side of the cylinder. This must be turned forwards in the cylinder block.
The connecting rods are symmetrical and can be turned freely. Marked rods however must be turned in the same direction.
Assemble the connecting rod and piston with the piston pin. Check that the classification and any numbering for each cylinder/piston diameter and connecting rod correspond.
Install both the snap rings on the piston pin. Check that the snap rings are positioned correctly in the piston. The opening must be vertical.
Wipe clean around the bearing recess in the connecting rod and the cap.
Installing the main bearing shells
Always use new bearings.
Check these for colour marking. The bearing shell with a black colour coding on the side (1) must be installed in the connecting rod.
Installing the pistons in the cylinder bores
Note! The arrow (top of the piston) must point forwards, and make sure that the classification matches.
Use a cylinder ring compressor.
Lubricate the cylinder bore, the pistons and the bearing shells.
Turn the crankshaft so that the connecting rod pin is at bottom dead center (BDC) for the cylinder the piston is to be inserted in.
Ensure that the engine is in a position where the cylinder bore forms as vertical a line as possible.
Carefully press or tap the piston down (using the shaft of a hammer or similar). When the piston releases from the piston ring compressor, turn the engine 180° in the stand.
Install tool 999 5746 Holder 999 5746 Holder in the connecting rod. Pull the connecting rod until it secures against the big end journals.
Tightening the connecting rod cover
Note! The crankshaft must not be rotated before the connecting rod cap has been tightened.
Install the cap. Check that any markings correspond.
Lubricate and install new screws. Tighten the screws. See Tightening torque Tightening Torque.
Check that the connecting rod can be moved sideways.
Installing the oil pump suction pipe
Install a new seal ring on the suction line.
Carefully press the suction pipe down into the intermediate section. Check that the sealing ring is correctly positioned.
Tighten the screws. Install new sealing rings for the oil ducts to the sump.
Installing the sump
Caution! Check that the rear edge of the oil sump is in line with the rear edge of the engine block. Permitted tolerance± 0.025 mm. Use a steel ruler and feeler gauge.
Wipe the surfaces dry.
Apply liquid gasket 11 61 059 on the oil sump. Use roller 951 2767 Roller 951 2767 Roller. The surface must be completely covered without any excess. Install the oil sump and install all bolts.
Tighten the screws. Start with the rear edge of the sump and work alternately forwards.
Installing the oil cooler
Install:
- new sealing rings in the oil pan
- the oil cooler. Tighten the screws
- the oil filter.
Cleaning
Caution! Cleaning shall always be done in the direction around the flange, not in and out. No grinding tools or similar may be used. It is extremely important that there is no remaining thread sealant or other dirt, as this may cause leakage.
Note! Use emery cloth 9511024 to clean the crankshaft end.
If necessary, wash off the oil on the rear cylinder block surface. Blow clean using compressed air.
When cleaning, work around the shaft journal, not in and out. It is essential that any residue from the emery cloth and any other contaminants are completely removed before the new sealing ring is installed.
Installing the rear crankshaft seal
Use standard handle 999 1801 STANDARD SHAFT 999 1801 Standard Shaft and drift 999 5676 Drift replaced by 9997174 999 5676 Drift Replaced By 9997174.
Lubricate the drift face. Thread the seal onto the drift. Tap in the seal until the drift bottoms against the block.