Mercedes-Benz W 108

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Mercedes Benz
Mercedes-Benz 280 SE (1972 US version)
Mercedes-Benz 280 SE (1972 US version)
W 108
Production period: 1965-1972
Class : Upper class
Body versions : limousine
Engines: Petrol engines :
2.5–4.5 liters
(96–147 kW)
Length: 4900-5000 mm
Width: 1810 mm
Height: 1440 mm
Wheelbase : 2750-2850 mm
Empty weight : 1470-1680 kg
Previous model Mercedes-Benz W 111 , Mercedes-Benz W 112
successor Mercedes-Benz 116 series

The Mercedes-Benz W 108 was a luxury class model from Daimler-Benz and was in production from mid-1965 to autumn 1972.

The W 108 series always had conventional steel suspension, while the 300 SEL with air suspension was referred to as the W 109 . The facelift in the spring of 1968 brought the transition from mechanical to electronic intake manifold injection .

The successors were the "S-Class" models from the W 116 series .

Model history

General

Rear view

In August 1965, a new generation of the upper class was presented with the types 250 S, 250 SE and 300 SE, which were to succeed the tail fin types W 111 (220 Sb, 220 SEb) and W 112 (300 SE). All three models had in common one of Paul Bracq drawn body whose contour at the Coupe series 111 W was oriented. With these models, the tradition began that the luxury coupé set a new style for the Mercedes-Benz brand.

The technical concept of the new types largely corresponded to that of the predecessor. In addition to the body (the tail fins of the previous W 111 series had been omitted), the two 2.5-liter engines that had been developed from the 2.2-liter M 180 engine by drilling out and enlarging the stroke were new. With these modifications, however, this engine concept of cylinders cast in pairs was at the end; the later 2.8-liter versions got an even cylinder spacing and subsequently proved to be much more stable and also more economical.

From January 1968 a revised version of the model series was offered. The changes affected, among other things, the range of engines, the interior and the design of the steering column. In the automatic versions, the selector actuation on the center lever was changed: the parking position P was initially at the rear, but in 1968 it moved forward, as was common practice. The steering wheel selector lever of the automatic was rarely chosen as an option because it was perceived as outdated. However, steering wheel gearshift levers were a prerequisite for driving with three people or two front passengers. To do this, a small seat cushion is placed in the storage tray between the seats and the center armrest with its padded underside is folded up so that two people can sit on the provisionally widened front passenger seat.

However, this type of "bench" use gradually disappeared in the 1970s. Buckling up two co-drivers was not possible; Driving without a seat belt was not compatible with the idea of ​​the best possible safety that Daimler-Benz always propagated. Versions with steering wheel shift levers and seat cushions can still be driven by three people in front.

technology

The carburettor engine of the 250 S had 96 kW (130 hp), the injection engine of the 250 SE developed 110 kW (150 hp), the engine of the 300 SE 125 kW (170 hp). The crankcase of this engine is made of an aluminum alloy .

The single-disc dry clutch with coil spring is hydraulically operated. The manual transmission has four gears and is fully synchronized. 300 SEb and SEL were available with a five-speed transmission from ZF . In contrast to the US versions, the automatic transmission for the European market, which is available at an extra charge, has four gears, but instead of a torque converter it has a fluid coupling consisting of a pump and turbine wheel, i.e. no stator wheel to increase torque. Because of the secondary oil pump driven by the output shaft, which ensures the lubrication of the transmission when the engine is not running, the car can be towed or towed.

The cardan shaft is in two parts with a joint with an elastic disc and two universal joints . The rear axle drive with hypoid drive toothing is slightly offset to the left, in the middle sits the downwardly offset joint of the single-joint pendulum axle, which is guided on trailing arms . There are coil springs on the links, but a large part of the suspension is taken care of by the balancing spring behind the differential gear. It supports the two semi-axles against each other and is intended to keep the camber constant with alternate suspension. The gas pressure shock absorbers are also attached to the semi-axles.

The front wheels are individually suspended on double wishbones with coil springs, telescopic shock absorbers and a stabilizer . The axle and the motor are mounted on a subframe , which is connected to the body at the rear by rubber bearings and at the front by leaf springs (which absorb the longitudinal forces).

The W 108 series had disc brakes on all four wheels from the start. A vacuum servo was part of the brake. The parking brake acts on the duo-servo drum brakes on the rear axle via cables .

The recirculating ball steering could be equipped with servo for an extra charge .

In contrast to its predecessor, the new 300 SE (with a short wheelbase, without "L") was no longer equipped with air suspension . Like the two 2.5-liter models, a hydropneumatic compensating spring in the middle above the joint of the single-joint pendulum axle was standard, which kept the level of the body constant. In the previous series, the so-called tail fins , this hydropneumatic compensating spring was only available as standard in the combination models called “Universal” and in the 230 S.

With the W 108, there was a choice between a short and a long wheelbase. The W 109 , offered from 1966 onwards, is always the long version (SEL). A feature of the W 109 is the standard air suspension; there are also differences in details in the engines (suspension for the compressor), in the interior fittings, the basic equipment and the doors.

Production of the 250 SE model ended at the beginning of 1968. The 280 S and 280 SE models were presented as successors in January, which differed from their predecessors only in terms of their engine and equipment details. The newly developed 2.8-liter six-cylinder engine has an output of 103 kW (140 hp) in the carburettor version (S) and 118 kW (160 hp) with intake manifold injection (SE). Production of the 300 SE model was discontinued at the end of 1967, while the 250 S model continued until 1969.

From the appearance of the W 108 series in summer 1965 until the end of production in autumn 1972, the injection sedans (250 SE, 280 SE, 300 SE, 3.5 series) were also donors of the same technology for the coupés and convertibles of the W 111 type (engines, Transmission, axles, suspension, brakes, steering, instruments and many more).

From March 1971 there was a 280 SE 3.5 and a 280 SEL 3.5. The engine of the type Mercedes-Benz M 116 had been offered in the W 109 (model 300 SEL 3.5) from 1969. The V8 engine had a displacement of 3.5 liters, 147 kW (200 hp) and was the first Mercedes-Benz with electronic manifold injection (Bosch D-Jetronic ). The 280 SE with a six-cylinder engine was still available, while the 280 SEL was withdrawn from the range in favor of the eight-cylinder model.

US versions

Initially exclusively for the North American market, parallel to the 3.5-liter V8 engine, a variant with increased displacement with 4.5 liters had been developed, which was introduced in May 1971 in the export models 280 SE 4.5, 280 SEL 4.5 and 300 SEL 4.5 ( W 109) was delivered. This was necessary in order to meet the American emissions regulations and, with a lower compression, the fuel in the USA, which at that time was still partially low-octane. The output of the 4.5-liter USA engines was 146 kW (198 hp), just about the level of the European engines with 3.5 liters.

There is one difference in the automatic transmissions of the 4.5-liter versions for the USA: they already correspond to the more modern type with a torque converter - but a three-speed automatic.

All three V8 engines, the "smaller" types 3.5 and 4.5 liters as well as the large 6.3 liter V8 engine (only in the W 109), were then also used in the successor model W 116 with a torque converter. The eight-cylinder got a three-speed, the six-cylinder a four-speed gearbox.

From mechanics to electronics

When construction began, the mechanical six-plunger injection pumps replaced the more simply constructed injection systems with two-plunger pumps and flow dividers, which were difficult to adjust and which were often noticeable with high consumption. In contrast to the simpler diesel injection pumps, these gasoline injection systems had a steel control cam ("space cam"). It was adjustable in two independent axes, namely it was moved lengthways according to the speed and rotated according to the load (accelerator pedal position). A fixed feeler roller determined the amount of fuel to be metered based on the radius at the moment. The complex, copy-milled space cam ("potato") depicts the engine's consumption map. There were also correction elements for warm-up and altitude.

The precision mechanical requirements of these Bosch systems led to the most complex maintenance and repair work on automobiles in the 1960s. These systems, with their manufacturing costs, peculiarities and defects, were then a reason to develop simpler systems in the 1970s.

The eight-cylinder with a displacement of 3.5 and 4.5 liters were the first series vehicles from Daimler-Benz to be fitted with an electronic injection system, the Bosch D-Jetronic.

Body styles

Mercedes-Benz W 108 with one-piece headlights
  • Sedan S and SE with conventional suspension (steel coil springs)
  • Sedan SEL - long version with wheelbase increased by 10 cm and steel suspension

Models: 250 S, 250 SE, 280 S, 280 SE, 280 SEL, 300 SE, 280 SE 3.5, 280 SEL 3.5 and 280 SEL 4.5 (US version)

Motors and drive

  • The 250 S and 280 S have two Zenith register carburettors ; the engines produce 96 and 103 kW (130 and 140 hp).
  • E denotes injection engines:
  1. The 250 SE, 280 SE (L) and 300 SE have six-cylinder in - line engines with mechanical six-piston injection pumps from Bosch and outputs of 110, 118 and 125 kW (150, 160 and 170 hp).
  2. The V8 engines ( M 116 / M 117 ) with a displacement of 3.5 and 4.5 liters (US version) have electronic manifold injection (Bosch D-Jetronic ) and engine outputs of 147 and 146 kW (200 and 198 hp).

Vehicles with a six-cylinder engine were supplied with a four-speed manual transmission as standard. A four-speed automatic transmission and, from 1969, a five-speed manual transmission, a very rarely ordered option , were available as special equipment . The eight-cylinder models had a four-speed automatic transmission with hydraulic clutch as standard (i.e. no torque converter) or, on request, the four-speed manual transmission, which was rarely ordered, was available at a reduced price. Only the 4.5 series models, which were delivered exclusively to the USA from 1971 onwards, had a three-speed automatic transmission with torque converter, which was also used in the successor model, the W 116.

A limited slip differential was optional .

Model overview and technical data

model Construction time
(approx.)
Model Engine type design type Cubic capacity

[cm 3 ]
Power

[PS] / [kW]
number of pieces 0-100
aut / man
[s]
V max
aut / man
Consumption

[l / 100 km]
250 p 7 / 65-3 / 69 108.012 M 108.920 R6 2496 130/96 74,677 14/13 177/182 12-14
250 SE 8 / 65-1 / 68 108.014 M 129.980 150/110 55.181 13/12 188/193 12
280 p 11 / 67-9 / 72 108.016 M 130.920 2778 140/103 93,666 12.5 180/185 12.5
280 SE 108.018 M 130.980 160/118 91.051 10.5 185/190
280 SEL 1 / 68-4 / 71 108.019 8,250
280 SE 3.5 7 / 70-8 / 72 108.057 M 116.980 V8 3499 11,390 10 200 13
280 SEL 3.5 108.058 951
280 SE 4.5 4 / 71-11 / 72 108.067 M 117.984 4520 198/146 13,527 9.5 205 14.5
280 SEL 4.5 5 / 71-11 / 72 108.068 8,173
300 SEb 8 / 65-12 / 67 108.015 M 189.989 R6 2996 170/125 2,737 12 195/200 18th

Variants and special equipment

The factory only had four-door sedans with two wheelbases. Occasionally, four-door sedans are said to have been converted into convertibles or landaulets .

Many S-Class vehicles in this series were converted to economical diesel engines at the advanced used car stage at the end of the 1980s . The mechanics of the tail fin models could be installed quite easily.

Numerous options were available:

  • Double or quadruple electric windows
  • Double or quadruple headrests
  • central locking system
  • Power steering, standard from 1968
  • Automatic, standard on the 280 SE / L 3.5, 4.5 (USA)
  • Five-speed gearbox (six-cylinder)
  • air conditioning
  • Electric sunroof
  • Forged Fuchs light alloy wheels ("baroque rims ")
  • Tinted sun protection glazing, partly standard on later models
  • Trailer coupling with fixed or removable ball head
  • Halogen headlights (double lights), with 300 SEL 6.3 (W109) and from 1969 series
  • Headlight washer system (from April 1972)
  • Searchlight
  • Tropical landing gear
  • Right wing mirror
  • Reading lights in the rear, standard on the 300 SEL 6.3 (W109)
  • Wheel arch chrome

Furthermore, Daimler-Benz also fulfilled unusual customer requests for a corresponding surcharge.

Export models

Mercedes-Benz 280 S (US version)

As standard, US export vehicles were “more environmentally friendly” than the other vehicles. The strict Californian approval regulations were achieved with lower compression and corresponding reduced performance, closed tank ventilation and afterburning of the exhaust gases. In addition, the carburetor engines had a V-belt-driven pump that blew air into the exhaust manifold.

In the USA, the sedans were offered with two circular headlights (sealed beam) one above the other, in accordance with American law. For European vehicles, one-piece, round headlights behind upright horseshoe-shaped lenses in two variants were the rule.

From 1969, similar double headlights were also offered for the European market. Since many older cars were converted to the more modern double headlights, the single long headlights are rarer and more popular today.

literature

  • Heribert Hofner: The S-Class from Mercedes-Benz. From the culture of driving. Bleicher, Gerlingen 1993, ISBN 3-88350-164-6 .
  • Alexander Franc Storz: Mercedes-Benz W 108/109. Motorbuch Verlag, Stuttgart 2016, ISBN 978-3-613-03906-3 .

Web links

Commons : Mercedes-Benz W 108  - Collection of pictures, videos and audio files

Individual evidence

  1. Purchase advice W108 . In: Daimler AG (Ed.): Mercedes-Benz Classic Magazin . No. 1 . Stuttgart 2015.
  2. http://sterntwiete.mparschau.de/html/einspritzung_2.html
  3. wiki.mercedes-benz-classic.com