Contents: Petrol models ↡ Diesel models ↡
Note: The parameters used when performing the procedures described in this Chapter are listed below. Detailed standard information can be obtained from authorized Mercedes-Benz service stations. Individual characteristics are also listed in the text of the Chapter and, if mandatory, are highlighted in bold.
Note: The values listed below are only those typical for all engines of the series under consideration.
Petrol models
General parameters
| Engine type | |
| V-shaped, 6-cylinder, DOHC, with water cooling, timing chain drive and microprocessor control |
| V-shaped, 8-cylinder, DOHC, with water cooling, timing chain drive and microprocessor control |
| Model range of application | |
| 112.945 |
| 113.962 |
| 113.982 |
| Engine capacity, l | |
| M112 | 3.2 |
| M113 | |
| 5.0 |
| 5.5 |
| Number of valves per cylinder | 3 |
| Compression ratio | 10.0:1 |
| Compression pressure, atm | |
| 12÷14 |
| 9.0 |
| 1.5 |
| Cylinder firing order | |
| 1-5-3-6-2-4 |
| 1-5-4-8-6-3-7-2 |
| Valve clearances | Automatic adjustment, - hydraulic compensators |
Cylinder head
Classification of cylinder head gaskets for engines
| Designation | Volume | Cylinder diameter | Marking |
|
| 112.945 | 3.2 | 92.00 | A 1120160320/0420 |
|
| 113.962 | 5.0 | 97.00 | A 1130100220/0320 | |
| 113.982 | 5.5 | No information available | No information available | No information available |
Cylinder head bolt sizes
| Thread | M11 |
| Length (L), mm | |
| 141.5 |
| 144.5 |
Valve guide bushings
Valve guide bushings seating diagram
1 — Inlet valve guide bushing
2 — Exhaust valve guide bushing
A — Bushing seat depth
L — Full sleeve length
| Diameter of the seat for the valve guide bushing, mm | |
| 12.500÷12.511 |
| 12.520÷12.531 |
| 12.700÷12.711 |
| 13.100÷13.111 |
| Outer diameter of valve guide bushing, mm | |
| 12.540÷12.551 |
| 12.560÷12.571 |
| 12.740÷12.751 |
| 13.140÷13.151 |
| Valve guide bush length, mm | |
| 50 |
| Geometric characteristics of the guide bushing, mm | A 14.3 ±0.2 |
Installation details and geometric parameters of valve seats (engines of series 112 and 113)
D1 — Socket for seating the inlet valve seat
D2 — Socket for seating the exhaust valve seat
a — Working angle of the chamfer
b — Upper correction angle
g — Lower correction angle
A — Width of the working chamfer of the saddle
Valve seats
Engines of the 112 and 113 series
A - Rod diameter
B — Length
C — Plate height
D — Plate diameter
a — Chamfer angle
| Geometrical parameters of valves (see accompanying illustration) | |
| D, mm | |
| M112 | |
| 36 ±0.1 |
| 41 ±0.1 |
| M113 | |
| 38 ±0.1 |
| 43 ±0.1 |
| WITH (for a new valve), mm | |
| 1.2 |
| 1.6 |
| A, mm | |
| 6.975 |
| 6.970 |
| B, mm | |
| M112 | |
| 119.40 ±0.2 |
| 122.25 ±0.2 |
| M113 | |
| 119.10 ±0.2 |
| 121.80 ±0.2 |
Cylinder block
Carter
| Cylinder diameter, mm | |
| M112 | |
| Standard size | |
| 89.900÷89.915 |
| 89.950÷89.965 |
| Repair size | 90.150÷90.165 |
| M113 | |
| Standard size | |
| 97.000÷97.015 |
| 97.050÷97.065 |
| Repair size | 97.250÷97.265 |
Crankshaft
| Dimensions of connecting rod bearing cap bolts (see accompanying illustration) | |
| Thread | M8x1 |
| Length, mm | |
| 47 |
| 47.6 |
Crankshaft thrust half-ring designations
Block cylinders | Crankshaft journal | Thrust half rings | Axial value shaft clearance, mm | ||
Designation. | Inscription | Designation. | Brands- rivka | ||
Code | N | O | N | Alphanumeric code | 0,10÷0,266 |
| Code | N1 | 1 | N1 | Alphanumeric code | 0,10÷0,266 |
Balance shaft (series 112)
Maximum permissible length of counterweight mounting bolt, mm | 50.7 |
Connecting rod and piston assemblies
| Piston diameter, mm | |
| M112 | |
| Standard size | |
| 89.872÷89.902 |
| 89.872÷89.902 |
| Repair size | 90.122÷90.152 |
| M113 | |
| Standard size | |
| 96.972÷97.000 |
| 97.022÷97.050 |
| Repair size | 97.222÷97.250 |
| Maximum permissible piston clearance, mm | 0.043 |
| The value of radial clearance of connecting rod bearings (new bearings), mm | 0.026÷0.054 |
Axial play of connecting rods
Color coding of the insert | Axial connecting rod size, mm | |
| Upper bearings (connecting rods) | Lower liners (covers) | |
| Yellow | Yellow | 0,026÷0,054 |
| Blue | Red | 0,026÷0,054 |
| Red | Blue | 0,026÷0,054 |
| Piston ring dimensions, mm | |
| Compression rings | |
| M112 | 83.2x1.5x3.1 |
| M113 | |
| 97.0x1.2x3.5 |
| 97.0x1.5x3.1 |
| Oil scraper ring | |
| M112 | 83.2x3.5x3.5 |
| M113 | |
| 97.0x1.5x4.0 |
| 97.0x3.5x3.5 |
Tightening force of threaded connections, Nm
| Engine oil pan drain plug (M14) | 30/32 |
| Oil filter housing cover | 25 |
| Self-tapping bolt for fastening the tensioner to the timing belt cover | |
| 35 |
| 25 |
| Belt tensioner damper mounting bolts | |
| auxiliary drives | |
| 25 |
| 35 |
| Tensioner mounting bolts | 25 |
| The union junction of the fuel supply line to the fuel line | 38 |
| Flange connection of the exhaust system inlet pipe with the exhaust manifold | 20 |
| Starter to engine crankcase mounting bolts | 42 |
| Bolts for fastening the front support cushions to the subframe | 35 |
| Bolts M8 for fastening the torque converter to the drive disk | 42 |
| Bolts for fastening the AT to the engine | |
| 40 |
| - |
| Hydraulic line fastening units to the steering pump | |
| Pressure line | |
| - |
| 45 |
| Return line | 2 |
| Screws for fastening the K/V compressor to the support bracket | 20 |
| Timing drive cover mounting bolts to block and cylinder head | 20 |
| Bolt M8x78 for fastening the guide pulley of the K/V drive belt and auxiliary units to the timing belt cover | 68 |
| Water pump mounting bolts | |
| |
| |
| 14 |
| 10 |
| |
| 35 |
| 25 |
| 10 |
| Fastening the water pump drive pulley | 10 |
| Thermostat housing mounting bolts (M6) | 10 |
| Steering pump mounting bolts | |
| |
| 35 |
| 20 |
| 25 |
| Bolts for fastening the intake manifold to the cylinder heads (M8) | 20 |
| Chain tensioner in the timing belt cover | 80 |
| Bolt for fastening camshaft sprockets (M12x45) | |
| 50 |
| Pull to a 90° angle |
| Hall sensor of the camshaft in the cylinder head | 8 |
| Bolts for fastening camshaft bearing bridges to cylinder heads | |
| |
| 15 |
| - |
| |
| 10 |
| Pull to a 90° angle |
| Bolts for fastening camshaft sprockets (M12x45) | |
| 50 |
| Pull to a 90° angle |
| Cylinder head mounting bolts | |
| |
| 10 |
| 30 |
| Pull to a 90° angle |
| Pull to a 90° angle |
| 20 |
| Cylinder head cover fastening bolts | 10 |
| Nut for fastening the connecting pipe to the EGR valve | 40 |
| Flange connection of the exhaust system inlet pipe with the exhaust manifold | 20 |
| Exhaust manifold mounting nuts | 16 |
| Engine end cover mounting bolts | 10 |
| Central bolt for mounting the vibration damper | |
| 200 |
| Pull to an angle of 95° |
| Bolts securing the drive disc to the crankshaft | |
| 45 |
| Pull to a 90° angle |
| Main bearing cap mounting bolts | |
| |
| |
| 20 |
| Pull to a 90° angle |
| 30 |
| |
| 30 |
| Pull to a 90° angle |
| Bolts for fastening the lower connecting rod head caps | |
| 5 |
| 25 |
| Pull to a 90° angle |
| Bolt M7x16.5 for fastening the locking plate to the balancing shaft (M112) | 15 |
| Counterweight to balance shaft mounting bolt (M112) | |
| 20 |
| Pull to a 90° angle |
| Bolts/nuts for fastening the rear support cushion of the powertrain suspension | |
| 35 |
| 35 |
| Nuts for fastening the cross beam to the car frame | 35 |
| Bolts for fastening the left and right side supports of the power unit suspension to the engine crankcase | |
| 20 |
| Pull to a 90° angle |
| Front suspension mount mounting bolts for powertrain | |
| 35 |
| 65 |
| Oil filter housing cover | 25 |
| Oil filter assembly housing mounting bolts | 70 |
| Fastening of liquid heat exchanger of oil filter | 11 |
| Oil pan drain plug (M14) | 30 |
| Self-tapping bolts for fastening the lower section of the oil pan to the upper | |
| 14 |
| 10 |
| Bolts securing the upper section of the oil pan to the cylinder block | |
| 9 |
| 20 |
| Oil level sensor mounting bolts | |
| to the upper section of the oil pan | 10 |
| Oil spray mounting bolts | 15 |
| Oil pump mounting bolts (M8x30) | 20 |
Diesel models
Note: The values listed below are only those typical for all engines of the series under consideration.
General parameters
| Engine type | |
| In-line (R), 5-cylinder, DOHC, turbocharged, water-cooled, timing chain drive |
| V-shaped, 8-cylinder, DOHC, turbocharged, water-cooled, timing chain drive |
| Model range of application | |
| 612.965 |
| 628.962 |
| Engine capacity, l | |
| 2.7 |
| 4.0 |
| Number of valves per cylinder | 4 |
| Compression pressure, atm | |
| 29÷35 |
| 18 |
| Maximum permissible difference in readings between cylinders | 3.0 |
| Cylinder firing order | |
| 1-2-4-5-3 |
| 1-5-4-8-6-3-7-2 |
| Valve clearances | Not adjustable, because hydraulic compensators are used |
Cylinder head
M612
Cylinder head bolt sizes
| Thread | M12 |
| Length, mm | |
| |
| 102 |
| 104 |
| |
| 107 |
| - |
(Material created based on the website: «MercedesMan»)
Details of the installation of valves in the cylinder head (612 series engines)
a - Fitting a new valve with a new seat
H — Cylinder head height
| Overall height of cylinder head, mm | |
| Nominal value | 126.85÷127.15 |
| Maximum permissible value | - |
Valve seats
Reaming of valve seats (612 series engines)
b — Width of the working chamfer
a — Angle of inclination of the working chamfer
g — Correction angle
| Geometrical characteristics of the valve seat | |
| All valves | |
| 45° (-30') |
| 1.0÷1.5 |
| 30° (±15') |
| 0.9÷1.1 |
| Maximum permissible ovality, mm | 0.03 |
Valves
D — Plate diameter
h — Height of the cylindrical part of the plate (belt)
D1 — Rod diameter
L — Valve length
| Plate diameter (D), mm | |
| 30.1÷30.3 |
| 28.3÷28.5 |
| Height of the cylindrical part (belt) of the plate (h), mm | |
| 1.7÷1.9 |
| Working chamfer angle (a) | |
| 45° (+15') |
| Rod diameter (D1), mm | |
| 6.960÷6.975 |
| 6.955÷6.970 |
| Surface reinforcement of the saddle | |
| Absent |
| Sodium filling | |
| Absent |
| Valve length (L), mm | |
| 104.7÷104.9 |
| 104.5÷104.9 |
| Identification marking of the plate | |
| E 611 01 |
| A 611 01 05 |
| Distance from the end of the valve stem to the base of the camshaft bearing (T), mm | |
| 17.1÷17.9 |
| Fitting a new valve with a new seat (a), mm | |
| 1.1÷1.5 |
| 1.0÷1.4 |
Series 628
Cylinder head bolt sizes
| Thread | M12 |
| Length, mm | |
| 201.5 |
| 203 |
Cylinder block
Series 612
Flywheel
| Maximum value of transverse runout of gear ring, mm | 0.4 |
| Diameter of centering sleeve of gear ring, mm | 276.05 (±0.05) |
Carter
| Main bearing bed diameter, mm | 62.500÷62.519 |
| Thrust bearing bed width, mm | 19.979÷20.000 |
| Maximum permissible value of ovality/taper of main bearing beds, mm | 0.02 |
Crankshaft
| Dimensions of main bearing cap bolts | |
| Thread | M11 |
| Length (L), mm | |
| 61.8÷62.2 |
| 63.8 |
| The values of crankshaft clearances in main bearings, mm | |
| |
| 0.03÷0.05 |
| 0.08 |
| |
| 0.10÷0.25 |
| 0.3 |
Main bearing shells
| Thickness of main bearing shells (upper and lower liners), mm | |
| Standard size (Ø 58.00 mm) | |
| 2.255÷2.260 |
| 2.260÷2.265 |
| 2.265÷2.270 |
| 2.270÷2.275 |
| 2.275÷2.280 |
Connecting rod and piston assemblies
| Piston protrusion (a) in a new crankcase, mm | 0.38÷0.62 |
| The value of the lateral clearance of piston rings, mm | |
| 0.12÷0.16 |
| 0.05÷0.09 |
| 0.03÷0.07 |
| The size of the gaps in the piston ring locks, mm | |
| 0.22÷0.42 |
| 0.20÷0.40 |
| 0.20÷0.40 |
| Connecting rod lower head mounting bolts | |
| 8x1 |
| |
| 47 ±0.3 |
| 48 |
1 - Connecting rod; 2 - Lower head cover; 3 - Bushing; 4 - Guide bushing; 5 - Bolt; 6 - Balancing weight; 7 - Marking area; 8 - Grooves for the tongues of the liners; 9 - Oil flow; 10 - Oil splash drilling
| Connecting rod dimensions | |
| Distance between the centers of the connecting rod bearing and the bore for the piston pin (L), mm | 148.970÷149.030 |
| Width of connecting rod heads (B and b), mm | 21.940÷22.000 |
| Inner diameter of the lower connecting rod head (D1), mm | 51.600÷51.614 |
| Maximum permissible values of ovality and taper of the connecting rod bearing bed, mm | 0.02 |
| Maximum permissible twisting of the connecting rod over a length of more than 100 mm | 0.100 |
| Maximum permissible value of misalignment of connecting rod heads, mm | 0.045 |
| Inner diameter of the connecting rod upper head bushing (d), mm | 30.018÷30.024 |
| Basic diameter of the connecting rod upper head bushing (d1), mm | 32.500÷32.525 |
| The clearance value of the piston pin in the connecting rod, mm | 0.018÷0.024 |
| Maximum permissible difference in weights of connecting rod assemblies, g | 2 |
Series 628
Carter
| Main bearing bed diameter, mm | |
| Base value | 74.500÷74.519 |
| 74.500÷74.506 |
| 74.506÷74.512 |
| 74.512÷74.519 |
| Thrust bearing bed width, mm | 25.29÷25.50 |
| Maximum permissible value of ovality/taper of main bearing beds, mm | 0.02 |
Crankshaft
| Dimensions of the lower crankcase mounting bolts (main bearing cap bridge) | |
| Thread | M11 |
| Length (L), mm | |
| |
| 113 |
| 115 |
| |
| 135 |
| 137 |
| The values of crankshaft clearances in main bearings, mm | |
| |
| 0.03÷0.05 |
| 0.08 |
| |
| 0.10÷0.25 |
| 0.3 |
Main bearing shells
| Thickness of main bearing shells (upper and lower liners), mm | |
| Standard size (Ø 70.00 mm) | |
| 2.252÷2.257 |
| 2.257÷2.262 |
| 2.262÷2.267 |
| 2.267÷2.272 |
| 2.272÷2.277 |
Connecting rod and piston assemblies
| Connecting rod lower head mounting bolts | |
| Thread | 8x1 |
| Length (L) (see accompanying illustration), mm | |
| 47 |
| 48 |
| The value of the lateral clearance of piston rings, mm | |
| 0.12÷0.16 |
| 0.065÷0.110 |
| 0.03÷0.07 |
| The size of the gaps in the piston ring locks, mm | |
| 0.40÷0.55 |
| 0.25÷0.50 |
| 0.20÷0.40 |
Tightening force of threaded connections, Nm
| All engines | |
| Oil filter housing cover | 25 |
| Fuel filter to air distributor mounting bolt | |
| 14 |
| 9 |
| Fuel filter mounting clamp screw (M612) | 9 |
| Series 612 | |
| Cylinder Head Cover Trim Panel Fastening Screws | 10 |
| Air Distributor Trim Panel Fastening Screws | 10 |
| Boost Air Distribution Hose Support Bracket Bolts | 20 |
| Steering pump pressure line mounting assemblies | |
| - |
| 45 |
| Hollow bolt of the union connection of the oil drain line to the radiator | 30 |
| Bolts for fastening the K/V compressor to the timing belt cover | 20 |
| Engine mounting bolts AT | |
| 40 |
| - |
| Front Cylinder Head Cover Fastening Bolts | 14 |
| Bolts for fastening the cylinder head to the timing cover (M8) | 20 |
| Bolts securing the timing belt cover to the engine crankcase | |
| - |
| 20 |
| Oil pan mounting bolts | |
| |
| 9 |
| 20 |
| - |
| 9 |
| 9 |
| Oil pan drain plug (M14) | 30 |
| Central bolt of the torsional vibration damper | |
| |
| 200 |
| Pull to a 90° angle |
| |
| 325 |
| Pull to a 90° angle |
| Bolts for fastening the K/V compressor to the timing belt cover | 20 |
| Bolts for fastening camshaft bearing caps to cylinder head | 9 |
| Exhaust camshaft sprocket mounting bolt | 18 |
| Fuel injection pump intermediate sprocket mounting bolt | 40 |
| Timing chain tensioner mounting bolt to timing drive cover | 80 |
| Cylinder head mounting bolts | |
| 20 |
| |
| 60 |
| Pull to a 90° angle |
| Pull to a 90° angle |
| Fuel injection pump pressure line nut/fuel distribution line | 20 |
| Front catalytic converter to turbocharger connection unit | 30 |
| Turbocharger Oil Drain Line Mounting Bolt | 9 |
| Turbocharger support bracket mounting bolts | 30 |
| Bolts of the air boost distribution sleeve | |
| - |
| 16 |
| Air duct clamps | 3 |
| Bolt for fastening the support bracket to the air boost tract distribution sleeve | 20 |
| Bolt securing support bracket to engine mounting bracket | 40 |
| Bolts for fastening the electric motor for shutting off the intake port to the air distribution sleeve of the boost tract | 9 |
| Exhaust manifold mounting nuts on cylinder head | 30 |
| Engine rear end cover mounting bolts | 9 |
| Flywheel/drive plate to crankshaft mounting bolts | |
| 45 |
| Pull to a 90° angle |
| Oil filter housing cover | 25 |
| Fastening of liquid heat exchanger of oil filter | 15 |
| Oil pan mounting bolts | |
| |
| 9 |
| 20 |
| - |
| 40 |
| 9 |
| Oil level sensor mounting bolts to oil pan | 14 |
| Oil pump mounting bolts | 18 |
| Bolts for fastening the lower connecting rod head caps (connecting rod bearings) | |
| 5 |
| 25 |
| Pull to a 90° angle |
| Crankshaft main bearing cap fastening bolts (M11) | |
| 55 |
| Pull to a 90° angle |
| Series 628 | |
| Ancillary drive belt tensioner in the engine crankcase | 30 |
| Front catalytic converter to turbocharger connection unit | 15 |
| Torque converter to drive disc mounting bolts (M8) | 42 |
| ATF Cooling Line Union Nuts/Hollow Bolts | 35 |
| Steering pump pressure line mounting assemblies | |
| - |
| 45 |
| Hollow bolt of the union connection of the oil drain line to the radiator | 30 |
| Bolt for fastening the refrigeration line to the compressor K/V | 20 |
| Engine mounting bolts AT | |
| 40 |
| - |
| Front Cylinder Head Cover Fastening Bolts | 14 |
| Pins for riveted timing chain links (approximate value) | 28 |
| Bolts for fastening camshaft bearing caps to cylinder head | 9 |
| Exhaust camshaft sprocket mounting bolt | 18 |
| Fuel injection pump intermediate sprocket mounting bolt | 40 |
| Timing chain tensioner mounting bolt to timing drive cover | 80 |
| Bolts securing the centrifuge cover to the engine crankcase | 8 |
| Cylinder head bolts | |
| 20 |
| |
| 20 |
| 60 |
| Pull to a 90° angle |
| Pull to a 90° angle |
| Pull to a 90° angle |
| Bolt securing oil return line to turbocharger | 9 |
| Turbocharger support bracket mounting bolts | 30 |
| Exhaust manifold mounting nuts on cylinder head | 30 |
| Engine rear end cover mounting bolts | 9 |
| Oil pan drain plug (M14) | 32 |
| Oil pan mounting bolts | |
| |
| 19 |
| 20 |
| - |
| 40 |
| 9 |
| Bolts for fastening the upper section of the oil pan to the engine block (M6) | 8 |
| Central bolt of the torsional vibration damper | |
| 275 |
| Pull to a 90° angle |
| 2-piece flywheel/drive plate to crankshaft mounting bolts | |
| 45 |
| Pull to a 90° angle |
| Oil filter housing cover | 25 |
| Fastening of liquid heat exchanger of oil filter | 15 |
| Fastening the ventilation line to the left intake manifold | 11 |
| Self-tapping bolts for fastening the lower section of the oil pan to the upper | |
| 12 |
| 8 |
| Oil pump mounting bolts (TORX) | 8 |
| Screws for fastening the cover with oil pipe to the oil pump assembly | 10 |
| Front support to bracket mounting nut | 110 |
| Bolts for fastening the lower connecting rod head caps (connecting rod bearings) | |
| 5 |
| 25 |
| Pull to a 90° angle |
| Lower crankcase section mounting bolts | |
| 8.5 |
| 20 |
| |
| 20 |
| 50 |
| Pull to a 90° angle |
| Pull to a 90° angle |