BMW M60

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BMW M60
BMW Alpina B8 4.6 Coupé E36 (7712800700) .jpg
Alpina B8 4.6 based on the BMW M60
overview
Manufacturer : BMW.svg BMW
Production period: 09 / 1992-1995
Combustion chamber
Design: V8 engine
Displacement variants : 3.0 l (2997 cm 3 )
4.0 l (3982 cm 3 )
Chronological order
Previous model: -
Successor: BMW M62

The BMW M60 is a V8 petrol engine made by the car manufacturer BMW . The engine was developed from 1984, and from September 1992 the BMW M60 went on sale in various models. According to the old BMW numbering system, there was already an M60 from 1977, which was then known as the BMW M20 and is known by this.

The engine was installed in the BMW 730i, 740i / 740iL of the E32 and E38 series , in the BMW E34 530i and 540i as well as in the BMW E31 830i (prototypes only) and 840i. In the BMW E34, the M60 replaced the M30. For the BMW E32 , the M30B30 was still offered parallel to the M60.

The BMW M60 was also used in other cars, of which the De Tomaso Guarà in particular is worth mentioning.

construction

Design features

The crankcase, constructed very compact and rigid with the help of CAD software, with a cylinder angle of 90 °, consists of an aluminum alloy (AlSi9Cu3), as does the oil pan and the cylinder head; as a result, the complete engine with add-on parts weighs only 209.4 kg (M60B30 with manual gearbox; M60B40: 213.2 kg), the bare block only weighs 25 kg and each of the two (different lengths) cylinder heads 30 kg. The cylinder head covers are made of a magnesium alloy.

The crankshaft with journals offset by 90 ° has five bearings and has two large and four small counterweights to improve running smoothness. The 3.0 l engine has a crankshaft stroke of 67.6 mm and the crankshaft is cast , the 4.0 l version has a crankshaft stroke of 80 mm and the crankshaft is forged . The connecting rods were produced for the first time in a BMW high-volume engine using the sintering process . The targeted breaking of the connecting rods (→  "cracked connecting rods" ) ensures maximum accuracy of fit and makes the conventional centering of the connecting rod and connecting rod cover using adapter sleeves superfluous.

The engine has two overhead camshafts with mass balancing ( eccentrically offset sections to compensate for engine vibrations ) per cylinder bank , which are driven by the crankshaft via double roller chains (duplex chain), with the drive going to the two inlet camshafts. From there, the exhaust camshaft is controlled via a further double roller chain. The identical camshafts for both M60 variants are designed as solid shafts made of chilled cast iron. They have five bearings, with the camshaft bearings being divided. Due to the different lengths of cylinder heads in each cylinder bank, the camshafts are also of different lengths. The valve angles are (as in the BMW M50 ) 20 ° 15 'on the inlet side and 19 ° 15' on the exhaust side.

The intake manifold made of reusable plastic ( nylon ), whose smooth plastic surfaces are characterized by their low flow resistance, is located between the two cylinder banks . Four valves per cylinder ensure the gas exchange, which are moved by bucket tappets with automatic hydraulic clearance compensation. The spark plugs sit in the middle between the four valves per cylinder and are controlled by a static ignition distributor , in which each spark plug has its own ignition coil. The engine management was taken over by the fully digital Bosch Motronic 3.3, which controlled the mixture with the help of a lambda probe (catalytic converter versions) and double knock control. For the export market (especially Eastern Europe and Asia) versions without a catalytic converter were also sold.

Coating of the cylinder liners

For the first time in large-scale production, BMW was the world's first automobile manufacturer to use a nickel dispersion coating for the cylinder liners on the eight-cylinder M60 engine. Since the aluminum alloy AlSi9Cu3 used for the crankcase does not have the required wear resistance, the surface of the cylinder bore had to be protected.

The cylinder crankcase of the twelve-cylinder BMW M70 engine is made of a hypereutectic aluminum alloy (with 17% silicon). After casting, the alloy was specifically cooled so that silicon precipitates formed on the cylinder liners during the solidification process. The silicon crystals were exposed by machining or etching the cylinder liners and, thanks to their good tribological properties , provided protection against wear. The disadvantage here, however, was that the pistons acting as friction partners had to be iron-coated and the piston rings had to be chrome-coated.

BMW has been providing the cylinder liners of motorcycle engines with a nickel dispersion layer since 1984. When coating a motorcycle crankcase, however, the entire crankcase is immersed. For the BMW M60, there was a further development of the so-called "flooding process". After the cylinder bore had been precision turned, a nickel dispersion layer was electrodeposited on the cylinder wall. Finely distributed silicon carbide (SiC) was embedded in the nickel layer in the nickel layer. Nickel thus serves as a binding agent or carrier layer, while SiC provides wear protection. The patented process makes it possible that only the cylinder bores themselves can be specifically coated in the desired shape and material thickness. Each borehole has a separate electrical circuit and is flooded separately. After the application of the nickel dispersion layer, it was removed in a final honing process by about half to 0.04 mm.

The process patented by BMW u. a. for the following reasons:

  • A “normal” and thus inexpensive aluminum alloy can be selected as the material for the cylinder crankcase.
  • The pistons do not have to be iron-coated.
  • The piston rings can remain uncoated.
  • At the time of coating, the crankcase can already be largely finished.
  • Subsequent coatings are possible.

Weak points

The BMW M60 is considered to be a robust and durable engine, provided regular maintenance and low-rev warming up. However, like practically every engine, the M60 has certain weak points.

The screws of the oil pump can loosen during operation and fall into the oil pan below. They should therefore be checked for tight fit immediately after the (used) purchase and, as a precaution, be permanently secured with screw locking. This means that regular checks are not required.

The M60 is equipped with ceramic catalytic converters ex works, with which the newer (round) variants can often collapse due to aging and then clog the exhaust; However, metal catalysts are also available in the accessories trade.

At the beginning of production, the BMW M60 suffered from engine damage, especially in the USA and Great Britain, which was attributed to a failure of the nickel-dispersion-coated cylinder sliding surfaces of the crankcase. The disadvantage with nickel-coated surfaces is the great sensitivity of nickel (and its alloys) to gases containing sulfur, i.e. H. the nickel sulfide formation at the grain boundaries leads to cold and red brittleness of the nickel.

In 1998, the US refineries produced fuels with sulfur contents between ≤ 100 ppm and sometimes> 500 ppm (≙ 0.05 percent by weight ). In early 2000, the EPA estimated that US fuel contained an average of 330 ppm sulfur. With the conclusion of Tier 2 , the US refineries were obliged to gradually reduce the sulfur content in fuel. For 2004, an average sulfur content of 120 ppm (maximum 300 ppm) was permitted, until 2006 sulfur limit values ​​of an average of 30 ppm (maximum 80 ppm) had to be complied with. This corresponds to the sulfur-free motor gasoline (which is common nowadays in Europe due to desulfurization ) .

Alpina

On the basis of the M60B40, Alpina built an engine of the same capacity with a higher output, which was used in the BMW-Alpina B10 4.0 (sedan and touring) and in the B11 4.0 and some B8 4.0 for Japan, with an output of 232 kW.

In addition, there was a second expansion stage with larger displacement with 4619 cm³, which was used in the B8 4.6 and the B10 4.6 (sedan and touring). This variant offers an output of 250 kW in the two B10s and 245 kW in the B8 due to a modified exhaust system.

Data

engine Displacement Bore × stroke Valves / cyl. compression Power at 1 / min Torque at 1 / min construction time
M60B30 3.0 l (2997 cm 3 ) 84.0 mm × 67.6 mm 4th 10.5: 1 160 kW (218 hp) at 5800 290 Nm at 4500 1992-1995
M60B40 4.0 l (3982 cm 3 ) 89.0 mm × 80.0 mm 4th 10.0: 1 210 kW (286 hp) at 5800 400 Nm at 4500 1992-1995
Alpina 4.0 l (3982 cm 3 ) 89.0 mm × 80.0 mm 4th 10.8: 1 232 kW (315 hp) at 5800 410 Nm at 4600 1992-1994
Alpina 4.6 l (4619 cm 3 ) 93.0 mm × 85.0 mm 4th 10.3: 1 245 kW (333 hp) at 5800 470 Nm at 4600 1992-1994
Alpina 4.6 l (4619 cm 3 ) 93.0 mm × 85.0 mm 4th 10.3: 1 250 kW (340 hp) at 5800 470 Nm at 4600 1992-1994

Valve control data

engine Displacement Engine control Valve stroke I / O in mm Opening angle ° CA I / O Spread inlet ° KW Spread outlet ° KW
M60B30 3.0 l (2997 cm 3 ) M3.3 9.4 / 9.4 246 ° / 242 ° 108 ° 108 °
M60B40 4.0 l (3982 cm 3 ) M3.3 9.4 / 9.4 246 ° / 242 ° 108 ° 108 °

use

M60B30

M60B40

  • 1992–1995 in the BMW E34 540i
  • 1992–1994 in the BMW E32 740i / 740iL
  • 1994–1995 in the BMW E38 740i / 740iL
  • 1992–1994 in the BMW E31 840Ci

Alpina F2

  • 1993–1994 in the BMW E34 (5er) Alpina B10 4.0 (Touring)
  • 1993–1995 in the BMW E32 (7 Series) Alpina B11 4.0
  • 1994–1995 in the BMW E34 (5er) Alpina B10 4.6 (Touring)
  • 1995–1997 in the BMW E36 (3 Series) Alpina B8 4.6

Individual evidence

  1. a b c Nickel dispersion for easy gliding . Optimal cylinder protection in the eight-cylinder engine. In: BMW AG (Ed.): Bayernmotor . BMW employee newspaper. No. 6 , May 5, 1992, ZDB -ID 558618-5 , p. 4 ( bmw-grouparchiv.de [accessed on October 15, 2016]).
  2. Patent DE3937763 : Method for producing a tread reinforcement and device suitable for this. Registered on November 14, 1989, published on January 7, 1993, applicant: Bayerische Motoren Werke AG, inventor: Götz Mielsch, Alfred Rutka.
  3. Nickel and nickel alloys . In: Werner Schatt, Elke Simmchen, Gustav Zouhar (Hrsg.): Construction materials of machine and plant construction . 5th edition. Wiley-VCH, Weinheim 1998, ISBN 978-3-527-62528-4 , Chapter 7: Materials for corrosive stress, p. 304 .
  4. ^ Regulatory Impact Analysis. (PDF; 2 MB) Control of Air Pollution from New Motor Vehicles: Tier 2 Motor Vehicle Emissions Standards and Gasoline Sulfur Control Requirements. US Environmental Protection Agency, December 1999, p. IV-60 , accessed October 11, 2016 (English, EPA420-R-99-023).
  5. a b Environmental Protection Agency 40 CFR Parts 80, 85, and 86. (PDF; 1.14 MB) Control of Air Pollution From New Motor Vehicles: Tier 2 Motor Vehicle Emissions Standards and Gasoline Sulfur Control Requirements; Final rule. gpo.gov, February 10, 2000, pp. 6729 + 6702 , accessed on October 11, 2016 (English, [AMS – FRL – 6516–2] RIN 2060 – AI23).
  6. Tier 2 Vehicle and Gasoline Sulfur Program. epa.gov, accessed October 11, 2016 .
Timeline of BMW gasoline engines for passenger cars since 1961
Number of cylinders Conception 1960s 1970s 1980s 1990s 2000s 2010s
0 1 2 3 4th 5 6th 7th 8th 9 0 1 2 3 4th 5 6th 7th 8th 9 0 1 2 3 4th 5 6th 7th 8th 9 0 1 2 3 4th 5 6th 7th 8th 9 0 1 2 3 4th 5 6th 7th 8th 9 0 1 2 3 4th 5 6th 7th 8th
3 1.5 l B38
4th (1.5–2.0 l) M10
M40
M42
M43
M44
N40
N42
N45
N46
N43
N13
N20
B48
High performance motor S14
6th Small six-cylinder (2.0-3.0 l) M20
M50
M52
M54
Large six-cylinder (2.5-3.5 l) M30
N52
N53
N54
N55
B58
High performance motor M88
S38
S50
S52
S54
S55
8th 3.0-4.4 l M60
M62
N62
N63
High performance motor S62
S63
S65
10 High performance motor S85
12 5.0-6.6 l M70
M73
N73
N74
High performance motor S70
Number of cylinders Conception 0 1 2 3 4th 5 6th 7th 8th 9 0 1 2 3 4th 5 6th 7th 8th 9 0 1 2 3 4th 5 6th 7th 8th 9 0 1 2 3 4th 5 6th 7th 8th 9 0 1 2 3 4th 5 6th 7th 8th 9 0 1 2 3 4th 5 6th 7th 8th
1960s 1970s 1980s 1990s 2000s 2010s