Mounting crankshaft in bearings - RA030A1193200X(03-3200)
Preceding work:
Engine removed and disassembled.
Oil galleries in crankcase and in crankshaft cleaned.
Crankshaft examined for cracks, dimension of tolerance, hardness and concentricity.
Operation no. of operation texts and work units or standard texts and flat rates
03-4700, 6401, 7021
- Engine 119.96/97 with fit bearing
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
DATA IN MMCrankshaft standard size and repair sizes Crankshaft bearing journal Ø Color Coding Crankshaft journal width at fit bearing (2) Crankshaft bearing journal Ø Crankshaft bearing journal width Standard size 63,9601 (1) → blau 27,000 47,965 50,000 63,965 27,021 47,955 50,100 63,955 (1) → gelb 63,960 63,950 (1) → rot 63,955 1st repair size 63,715 max.27,50 47,715 63,700 47,705 2nd repair size 63,465 47,465 max.50,30 63,450 47,455 3rd repair size 63,215 47,215 63,200 47,205 4th repair size 62,965 46,965 62,950 46,955 (1) Tolerance division for bottom bearing cap, colored dots on crank webs or counterweights next to crankshaft bearing journals (2) Crankshaft main bearings with fit bearing as of engine no. 119.96 as of start of production up to engine no. 119.970 12 036277 119.971 12 017447 119.972 12 004797 119.974 12 008072 119.975 12 010516 CRANKSHAFT BEARING BORE, CONROD BEARING BORE AND BEARING PLAY IN MMCrankcase (2) Color coding Conrod Crankshaft bearing bore 68.480 (1) → blue - 68.486 yellow 68.486 (1) → red 68.492 68.492 (1) → 68.500 Conrod bearing bore - - 51.600 51.619 Permissible out-of-roundness and conicity of bores 0.01 0.01 Radial bearing play when new 0.021-0.045(3) 0.030-0.055(3) wear limit 0.090 0.080 Axial bearing play when new 0.10-0.22 0.22-0.38 wear limit 0.30 0.50 (1) Tolerance division for top bearing cap, chisel punch points in contact surface of crankcase at oil sump end. (2) Machined together with crankshaft bearing cap. (3) Aimed for average value of radial bearing play. MATCHING CRANKSHAFT BEARING SHELLS TO CRANKCASEChisel punch points on crankcase Matching top bearing shell with color coding 1 punch point 2 punch points 3 punch points Colored dots on crankshaft bearing cap Blue Yellow Red Color of top bearing shell Blue Yellow Red Color coding on crankshaft Matching bottom bearing shell with color coding Blue Yellow Red Color of bottom bearing shell Blue Yellow Red TIGHTENING TORQUES IN NMCrankshaft bearing stud bolt Stud bolt in crankcase(1) 30 M10x1 nut 50 M10x40 side bolts (10.9) 50 (1) The stud bolts lose their locking effect after being unscrewed and must therefore only be used once. Special tools
COMMERCIALLY AVAILABLE TOOLSQuick-callipers for internal measurements, dia. 40 - 60 mm e.g. Hahn und Kolb
Borsigstraβ 50
D-7000 Stuttgart 30
Order no. G 222 KQuick-callipers for internal measurements, dia. 60 - 80 mm Order no. G 322 K Micrometer 25 - 50 mm Order no. 31346 025 Micrometer 50 - 75 mm Order no. 31346 050 NOTE: Self-locking stud bolts are screwed into the crankcase for securing the crankshaft bearing caps. These stud bolts may only be used once as the locking adhesive applied over approx. 8 mm length of the thread is no longer effective when they are removed.Pay attention to the different insertion depth and collar dia. when replacing the stud bolts.
When performing repairs, no HELI-COIL inserts may be used for the self-locking stud bolts of the crankshaft bearing caps.
The 5 crankshaft bearing caps manufactured from malleable cast iron are fitted into the side in the crankcase (arrows).
The fitting face (arrows) is positioned off-centre so that the bearing caps can only be installed in one position.
The three center bearing caps are additionally bolted to the housing side walls.
The crankshaft bearing caps are machined together with the crankcase and are not available as a replacement part.
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
If bearing damage has occurred, the conrods must be removed and any swarf removed from the conrod bores and the oil passages of the crankshaft.
Carefully clean the oil passages in the crankcase, crankshaft, timing case cover, oil filter housing, closing cover, oil pump etc.
Examine crankshaft for cracks, dimensional tolerance and hardness (03-3180) .
Matching crankshaft bearings, installing crankshaft
- Install crankshaft bearing caps, pay attention to marking, 1 is to the front.
The fit face is asymmetrical (arrows); the crankshaft bearing caps can thus only be installed in one position.
- Oil thread and contact surface of nuts, tighten nuts to 50 Nm.
- Oil thread and head contact surface of side bolts (M10 X 40), install with the washers and tighten to 50 Nm.
- Measure crankshaft bearing bore in direction A, B and C at two levels (conicity); note measured values.
If a crankshaft bearing bore exceeds the specified value or is conical, dress bearing cap at its mating surface on a dressing plate up to max. 0.02 mm.
- Insert bearing shells, install crankshaft bearing cap.
Tighten nuts and side bolts to 50 Nm.
- Measure bearing diameter and note.
- Measure crankshaft bearing journals, determine radial play of crankshaft bearing.NOTE: The bearing play can be connected by replacing the bearing shells (see table Matching crankshaft bearing shells to crankcase); in this case, aim for the average value of the bearing play stated.
- Measure width of fit bearing journal and of fit bearing. Determine axial play of crankshaft.
The fit bearing shells of the repair sizes are supplied oversized.
- Moisten bearing shells and crankshaft with SAE 30 engine oil and insert crankshaft.
Install bearing shells with oil drilling into the crankcase.
- Tighten crankshaft bearing caps to the specified torque in the order of the tightening diagram. Oil the thread and the bolt head or nut contact surface for this step.
Nuts 50 Nm.
Side bolts 50 Nm
NOTE: Bolts of quality 10.9 should be used for the side bearing cap fixture. - Measure axial play of crankshaft.
- Rotate crankshaft by hand and check whether it runs freely.
Matching conrod bearings and installing
- Examine conrod bolts (03-3100) .
- Repair and align conrod (03-3130) .
- Insert conrod bearing shells, install conrod bearing caps with conrod bearing shells and tighten conrod nuts or bolts to 35 Nm.
- Measure bearing diameter and note.
- Measure conrod bearing journal. Determine radial play of conrod bearing.NOTE: The bearing play can be corrected by replacing the conrod bearing shells; if this step is performed, aim for the average value of the specified bearing play.
Crankshaft bearing shells without color coding are thicker than those with blue color coding, although it should be noted that the wall thicknesses without and with color coding may overlap.
- Install pistons and conrod (03-3160) .
- Moisten bearing shells, crankshafts, pistons and cylinders with SAE 30 engine oil. Install conrod with pistons (03-3160) .
Pay attention to marking.
Install the bearing shells with the oil drilling in the conrod otherwise the conrod bushes will not be lubricated.
- Tighten conrod nuts and conrod bolts (03-3100) .
- Measure axial play of conrod bearings. Examine clearance of conrod in the piston.
Disassemble oil pump, clean, renew if necessary. Replace oil delivery valve. Clean oil filter, carefully clean air-to-oil cooler or replace.
Install initial operation oil filter element. Change engine oil and oil filter element after 1000 - 1500 km.
- Install crankshaft bearing caps, pay attention to marking, 1 is to the front.