Further reading on 5 & 6 Series BMW cars

BMW 5 Series Service Manual 1982-1988 (E28)
The BMW 5 Series (E28) Service Manual: 1982-1988 is a comprehensive, single source of service information and specifications for BMW 5-Series (E28) cars from 1982-1988. Whether you're a professional technician or a do-it-yourself BMW owner, this manual will help you understand, maintain, and repair systems on 5-Series cars. Complete preventive maintenance procedures from the yearly brake fluid change to resetting the oil service indicator and oxygen sensor lights. This manual tells you what to do, how and when to do it and why it's important. Many of the maintenance recommendations exceed factory-recommended service intervals and are designed to extend your BMW's service life. Detailed troubleshooting and repair information for these Bosch fuel injection and engine management systems: Motronic (528e, 533i, 535i, 535is) and Motronic 1.1 (528e from March 1987).


This Motronic 1.1 service information is not covered in BMW's factory repair manual. Comprehensive Engine Management information for specific BMW 5-Series driveability problems, including troubleshooting electronically controlled idle speed faults that are frequently misdiagnosed. Troubleshooting tips with fast, proven repair procedures used by BMW technicians and specialists. Critical updates and hard to find information from dealer service bulletins, such as how to replace the camshaft timing belt, sprocket and tensioner with the correct Z-127 update, and cylinder head bolt replacement on 528e models. Large, easy to read wiring schematics for major circuits, along with a full listing of ground points, connector and splice locations, and electronic component locations. Procedures and specifications for rebuilding engines and manual transmissions. With 548 pages 758 illustrations and diagrams. Hard B.


ISBN: 9780837616940

BMW 5 Series Service Manual 1989-1995 (E34)

Covers models: 525i, 530i, 535i, 540i, including Tourer. This manual is the only comprehensive, single source of service information for BMW 5 Series from 1989 to 1995. The aim throughout this manual has been practical explanations & step-by-step procedures. Whether you're a professional or a do-it-yourself BMW owner, this manual will help care for & repair your E34 5 Series. Maintenance procedures from brake fluid changes to resetting the Service Indicator.


This manual tells you what to do, how and when to do it, and why it's important. Engine and cylinder head service, repair and reconditioning, including M50 and M60 timing chain setup and adjustment. Extensive engine management information for specific BMW 5-Series driveability problems, including reading Check Engine light fault codes. Transmission maintenance, troubleshooting, adjustment and repair, including hydraulic clutch, gearshift linkage, and driveshaft. Body adjustments and repairs, including sedan sunroof removal and adjustment. Heating and air conditioning repair, including A/C micro-filter and A/C component replacement. Wiring schematics for all circuits, including power distribution, grounds, and component locations.

Comprehensive BMW factory tolerances, wear limits, adjustments, and tightening torques that you've come to expect from Bentley manuals. 525i (M20 with DME 1.3) 1989-1990, 525i (M50 with DME 3.1) 1991-1992, 525i (M50TUA/ANOS with DME 3.3.1) 1993-1995, 530i (M60 with DME 3.3) 1994-1995, 535i (M30 with DME 1.3) 1989-1993, 540i (M60 with DME 3.3) 1994-1995. Manual (remove, install, external service) Getrag 260/5 and 260/6, Getrag S5D 250G, Getrag S6S 560G, Automatic (remove, install, external service) ZF 4HP22/EH, A4S 31 OR (THM-R1), ZF A5S 310Z, ZF A5S 560Z. A total of 672 fully illustrated pages. Soft Bound.


ISBN: 9780837603193

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Chapter 1 – E12

The E12 in the USA

E12 Overview


Overhauling and repair


Cooling System









E12 Specifications

Chapter 2 – E28

E28 Timeline

The E28 In the USA

E28 Overview



Fuel system

Cooling system, heating and air conditioning


Manual gearboxes

Front suspension


Body Trim

Body restoration

Chapter 3 – E34

The E34 in the USA

Checking out an E34

E34 overview


Overhauling and repairs - quick maintenance guide


Cooling System






Wheels and Tyres



E34 Specifications

E34 M5 Specifications

Chapter 4 E24 – 6 Series

Wheels and Tyres

Engine and gearbox

Suspension and brakes



The US market 6 Series


Useful addresses



It is now 40 years since the first BMW 5 Series went down the production lines at Dingolfing. Back in 1972, only the BMW executives with the greatest of foresight could have predicted that in 2012, the 5 Series would still be in production and still be the class leader - and it's amusing to note that the latest model - the F10 520i - is also a two litre four cylinder just as those first Fives were.

BMW occupies a unique position in the hearts of car buyers and enthusiasts for no other marque of car has such a wide fan base. From what are probably the finest range of cars in the world to an enjoyable secondhand car, through to concours events, track days to drifting championships plus huge clubs and countless forums, no other manufacturer has such a huge and diverse following as BMW. The large numbers of the first three generations of the 5 Series that still survive attest to that, and this book is aimed at owners wanting to know more and pick up some useful maintenance, repair and restoration tips.

BMW for their part have not quietly forgotten their older cars - for too many manufacturers, once a car has been discontinued and all examples sold, that tends to mark the end of any interest. BMW though have an enviable reputation for maintaining parts stocks and the fact that they still supply the majority of essential parts for a 40 year old car speaks volumes. Their BMW Classic (formerly Mobile Tradition) division is going from strength to strength and only Porsche and Mercedes Benz can equal them in terms of parts supply.

Thanks are due to so many people and BMW AG themselves for allowing the use of so much of their invaluable copyright technical information. Hopefully this book will result in more parts sales!

For photos, thanks are due to Richard Baxter, Morrison Yinusa, Ian Ewen, Mark Lawless, Dan Kelly, Tony Chamberlain, Tris Foulds, Paul Wager, Craig Sterry, Matt Woods, Steve Bostock, Nick O'Kane and Derin Oloyede. Thanks are also due to Kos Loizou from the BMW Car Club for photos of his red 1986 635CSi and for pictures of the grey Motorsport Highline. Peter Walsh, Phil Crouch of CPC Performance Engineering and Parkside Garage also helped out. Also requiring a hefty mention are Dutch classic car specialists Auto Ruyl who have a healthy trade in classic BMW's and allowed us use of their E12 and E28 photos - many thanks for that.

Finally, to my late Father, Geoff Everett who was BMW GB's technical manager in 1982-4. Had it not been for that gleaming new E28 520i whispering up the gravel drive to pick me up from school in November 1982, my own passion for the blue and white propeller may never even have started.

Andrew Everett

Chapter 1


The E12 arrived in late 1972 as a replacement for the long running Neue Klasse (new class) models that had pretty much run out of steam. The New Class started life at the 1961 Frankfurt show as a 1500, went into production the following year and became a 1800 in 1963, a 1600 joined it in 1964 and the 2000 arrived in 1966.

The New Class was a very good car but it was a bit small and narrow - whilst it was never really a competitor to the 190-200 Mercedes, BMW took the opportunity to make its successor longer and wider and thus be more of a competitor to the 1968 ‘New generation’ Mercedes cars.

The E12 was a clever repackaging of existing BMW parts and the engines were revised versions of the existing 2000 four cylinder and ‘E3’ six cylinder units.

The E3 was BMW’s larger saloon introduced in 1968, and the E12 borrowed much of it’s suspension and brakes.

The E12 was introduced in late 1972 with a UK launch in March 1973. There were only two models initially, both four cylinder. The 520 was a replacement for the BMW 2000 and it featured a carburettored 1990 cc M10, the engine that powered both the 2000 and the smaller two door 2002. For the E12 though, BMW revised the combustion chambers and the piston tops and the new E12 engine was also fitted to the 2002 from late 1972 onwards. The obvious difference though was in the 520’s carburation. Rather than use the twin choke Solex from the 2002, BMW elected to use a pair of Stromberg CDET 175 carburettors which gave the revised two litre a power output of 115 bhp - just enough to haul the new 1235 kilo 520 along at a respectable rate of knots.

The compression ratio was 9:1, and power was fed through a four speed Getrag 242 gearbox and a 4.1 ratio final drive. Tyres were 175 SR × 14 radials on 5 inch wide steel wheels and of course, these cars were pretty basic. No power steering or electric windows, but it had a rev counter, a clock built into the rotary heater fan control (later replacing the rev counter), heated rear window, cloth velour trim, electric screen washers and a laminated windscreen.

With 115 bhp, performance was okay if not startling. 0-60 came up in 11.3 seconds with an 18 second quarter mile and a screaming top speed of 109 mph. At £2995 in 1973, the 520 was not a cheap car. A 4.2 litre XJ6 was only £72 more and a lot of faster 2 litre cars were much cheaper with a Cortina 2000GXL being half the price.

If the 520 was too much money for not enough go, the 520i was even more expensive at an eye watering £3499. Heart of the 520i was the fuel injection engine from the 2002Tii with mechanical Kugelfischer injection and 130 bhp The same four speed 242 gearbox was used, but the final drive ratio was usefully raised to 3.91. Tyres were the same 175 profile but were now an HR rating radial and the wheels were now 5.5 inches wide to reduce side wall flex. A slightly uprated front anti roll bar (22 mm, up from 21 mm of the 520) and standard 16 mm rear anti roll bar were used but the same Boge dampers were fitted - apart from that though, the 520i was the same as the 520. Performance was notably better with another 15 bhp - 0-60 took 10.5 seconds, the 1/4 mile took 17.5 seconds and top speed was up to 116 mph at 6270 rpm. You’d recognise a 520i not only by the extra i’ on the boot badge, but also by the ‘520i’ badge on the grille - the 520 only had a boot badge.


Revised E12 rear end from Sept 1976


Maroon E12 Auto 34 - Malaga red 520 Auto from 1973 (Ruyl)

Sales in the UK were okay but unspectacular, and in those days BMW were not chasing huge volumes.

Later in 1973 saw the first of the six cylinder models, the 525. The 2494 cc M30 engine from the 2500 E3 saloon was a decently tight fit in the engine bay and it used stronger front springs and dampers along with 520i anti roll bars, a wide but slim radiator similar to an E3 unit and 2500’s Getrag 262 four speed gearbox. The engine was rated at 145 bhp, 5 bhp less than the 2500 saloon even though the 9:1 compression ratio, camshaft profile and twin 35/40 INAT carburettors were the same. A 3.64 final drive unit from the 2500 was fitted along with the wheels and tyres from the 520i plus rear disc brakes. The 525 had chrome model insignia front and rear like the 520i. Whilst the 525 was never a popular model in the E12 range, it was a nice car with a distinct character. With the taller final drive and extra torque - plus that lovely six cylinder growl that BMW’s were famous for - the 525 was a much nicer every day car for owners who used their cars on longer trips. At £4024 though, it had serious competition although it has to be said, it was a much better car than the much slower and much thirstier Mercedes 250 that was also £400 more.


Maroon E12 Auto Carbs - Early 520 Stromberg carburettors in detail (Ruyl)


Malaga Red E12 520 Automatic

In pure performance terms, the 117 mph 525 wasn’t much faster than the 520i - the actual figures were very similar and it was only 2 seconds faster to 90 mph. The taller gearing made it slightly more economical though to the tune of 1 mpg, and the tall gearing meant that 80-90 mph cruising was far less rackety.

Late 1974 brought the model everyone was waiting for, the 528 that was launched in the UK in January 1975. With 170 bhp to propel it along on the same 3.64 final drive, the 528 was usefully fast - 122 mph, 9 seconds to 60 mph and 16.9 seconds to cover the quarter mile. An automatic version with a Borg Warner Model 65 autobox was almost as fast on paper although the gearbox was not especially good. 195/70 × 14 tyres on 6 inch wide wheels gave it more grip and uprated suspension tightened it up a tad with standard power steering from October 1975 making it easier to drive - PAS was also made standard on the 525. Inside all was the same as the 525, but the 528 buyer was given matt wood trim strips on the doors to match the ones on the dashboard.


Early 520 facia with clock - This Shot of a ’79 520 Shows the heater controls

At £4989 it was very expensive of course, but BMW were offering something you couldn’t buy anywhere else - a four door that was genuinely fast with good road manners and reasonable economy. Mercs with similar performance were a lot more money and Jaguars were heavy on fuel and plagued with reliability and build quality problems.

1974 was the era of the fuel crisis that claimed the 3.0CSL and the 2002 Turbo, BMW’s two shining stars. In their place came the 518.

The 518, launched in the UK in January 1975, was BMW’s economy special which was really nothing of the sort. What it represented was BMW injecting some life into the 4 cylinder E12 sales, which it did nicely.

To look at, the 518 was like the 520 with just the boot badge betraying the 1800 engine (actually 1766 cc).

This engine was lifted from the 1802 (not sold in the UK) and early versions until July 1975 used a single choke Solex 40 PDSI carburettor that resulted in a very sluggish car. After that they were fitted with a twin choke 32/32 DIDTA carburettor which added a bit of sparkle.

To reduce the cost, the 518 was fitted with a clock rather than a rev counter (the 520 was also given a standard clock at around this time), the rear anti roll bar was deleted and a cheaper type of trim was used. To keep acceleration around town up to scratch, a 4.44 final drive ratio was used but this made the 518 hopelessly undergeared on the open road - by 60 mph it was very busy and even 80 mph required more than 5000 rpm.

1975 didn’t see any noticeable changes, but from July the 520 used the revised M10 engine from the new E21 320 - mainly cylinder head and piston crown changes plus rejetted CDET carburettors and a revised exhaust rear box. October 1975 saw the final end to Kugelfischer injection as the 520i took on the E21 320i engine with it’s revised cylinder head, pistons and Bosch K Jetronic electro-mechanical injection system and revised exhaust. Slight revisions were made to the 242 manual gearbox, but nothing worth getting too excited about, and the old 3HP12 (4 cyl), 3HP20 (525) and BW65 autoboxes were replaced by the all new 3HP22. February 1976 saw a change to the front struts with the threaded damper collar ring changed from M50 to M48.

But later in 1976 saw the E12’s one and only facelift that was announced in September. The most noticeable change was at the rear where the rear lights were now much wider and chunky looking. The fuel filler flap was moved from the rear panel to the offside rear quarter panel (requiring a new fuel tank) and the bonnet was restyled with a raised centre ridge and the front grille was made taller with the top sitting in a raised cutout in the bonnet.

520 and 520i cars remained similar mechanically, but the 525 and 528 lost their two INAT carbs, replaced by a new four barrel Solex 4A1. All cars had an improved ventilation system with four extra dash vents and a new one piece four spoke steering wheel replaced the similar looking original which had a shiny rim and removable centre pad. The 525 and 528 cars were now available with an optional leather steering wheel from the new 6 Series. An electric door mirror was now standard and the sunroof revised, now having both tilt and slide.

1977 was another year of big change. August / September is when it all happened and we might as well start with the 520 and 520i. These four cylinder cars were both discontinued (as were the four cylinder E21 320 and 320i) and replaced by the new six cylinder 520.

Under the bonnet was the all new M60 1990 cc engine, a straight six unit with an iron block and alloy head not dissimilar in design to the other BMW engines, but with a rubber toothed belt to drive the cam and a four barrel Solex 4A1 similar (but not the same) to the one used on the 525/528 cars.

The new engine gave 122 bhp putting it right between the old 520 and 520i four cylinder cars, and whilst it wasn’t the fastest thing on earth it made the 520 a very smooth and lovely sounding car that was now a world apart from the Mercedes 200 with which it competed. A new version of the Getrag 242 was fitted with a revised bellhousing pattern, and the 3.91 final drive from the old 520i was used.


Late 1976 520 shows revised front end and early wheels


1977 520 shows the revised tail lights for September ‘76


Shot of a Reseda Green 1979 520 - note raised grille


Facia in a 1979 520 Automatic - no rev counter


E12 528i M528i engine bay


Late E12 518 engine bay - note brake linkage

After a year with the Solex 4A1 - a move which never really worked - the 528 was given Bosch L Jetronic fuel injection and became the 528i. The old 528 was a nice car but the 4A1 carb didn’t give any more power and was detrimental to fuel consumption. Not only that, but cars like the Rover SD1 3500 were catching up and BMW needed to give it a shot in the arm. The 528i was certainly a huge improvement. L Jetronic gave the 2.8 litre M30 superb throttle response, and 177 bhp was not to be sniffed at. Aided by a taller 3.45 final drive, the 528i was a very fast car back in the day and would rocket to 60 mph in 8.7 seconds and go on to 130 mph. A Sport gearbox with the ‘dogleg’ gearchange pattern (where first gear is over to the left and back) was available as an option but it was very rare - the standard car was fast enough. To complement it’s new performance BMW not only offered this gearbox, but also Bilstein sport suspension and a limited slip diff. These options had in fact been introduced with the face lifted 528 in August 1976 but were ‘pushed’ more with the 528i that was a fast and good handling car which could still catch the unwary - especially in the wet. The big four wheel discs (with vented fronts) were carried over from the 528 and proved to be more than up to the job.

September and August 1977 also saw a couple of cosmetic changes. The steel wheels were replaced with new design open lug wheels from the E23 7 Series, the E23 style steering wheel with ribbed horn buttons and smooth centre section was phased in, the bootlid badges lost the black plastic backing and the ‘automatic’ badge fitted to auto equipped cars was finally discontinued.

1978 came and went with no noticeable changes to the E12, but there were a few detail changes. In August 1978, the 518, 520 and 525 finally lost the twin servo brakes and were fitted with an E21 style single master cylinder with a vacuum servo, mounted on a long box section mount with pushrod operation. The 520, 525 and 528i also got transistorised electronic ignition the same month, meaning that only the 518 retained the old points and condenser type ignition until 1980.

August 1979 saw the end of the analogue clock that lived in the centre of the heater blower switch - from now on it was a digital unit, standard on the 525 and 528i and optional on the 518 and 520. Also changed were the seat runners, changed from a side release catch to a conventional front lever.

1980 was the last full year for the European E12, but a few changes were made. For the 1980 model year, electric drivers mirrors, seat mounted seat belt stalks, rear seat area heating and rear lap belts were standardised for all cars. A five speed close ratio Sport gearbox was introduced as an option for the 520. A five speed overdrive box became an option on the 525 and 528i cars.

April 1980 was the month for the big news though, the M535i. BMW Motorsport created this by fitting the running gear from the full Sport specification 635CSi into a 528i shell - the 218 bhp 3453 cc engine with L Jetronic (the Motronic version from late 1980 was never used), close ratio sport gearbox, 3.07 ratio limited slip diff with an extra oil carrier/cooler and suspension with Bilstein dampers and uprated springs.

In Europe these were available as a standard version with chrome front and rear bumpers, but when the RHD production started, the UK versions all had the plastic one piece front bumper with integral spoiler which had been an M Technic accessory spoiler since August 1976 but was rarely seen. All cars came with a three spoke sports steering wheel as standard, either the standard fit version with three horn buttons on the spokes or an optional smaller one from the E21 3 Series with a centre horn push. Recaro sports seats were also standard on the M535i as were 14 inch Mahle BBS cross spoke ‘lattice’ alloy wheels.

Standard tyres were 195/70 VR 14 on 6.5 inch wide wheels, but an optional 7 inch wide ‘Motorsport’ wheel was available with longer wheel bolts. Most M535i cars had a chunky rear boot spoiler whose badge position seems to vary. Some cars had no badges, some had the BMW roundel in the centre and others had either the M badge, the 535i script or sometimes both…..

September 1980 saw the old DIDTA carburettor on the 518 replaced by the new Solex Pierburg 2B4 with an electric idle solenoid and vacuum control for the second choke along with TCLi electronic ignition, and a five speed gearbox fitted with a synchronised reverse gear on the 525 and 528i. M10 and M30 engines also began to change over from the duplex timing chain to a single row chain. At this point, the M10 engines used a different distributor (the electronic ignition type) that worked the other way around and cannot be interchanged - you won’t have any ignition advance!


1979 E12 528i with E28 Spoiler

By 1981, the writing was on the wall for the E12 and the last cars were built in June 1981 as the next generation E28 was about to take over. The final changes came in January 1981 with the 520 gaining standard power steering and a rev counter as well as central locking - this would appear to be mainly the automatic model for some reason.

The E12 started off as an expensive, undergeared car with superb build quality, and ended its life as a very thoroughly sorted car which could have run for another two or three years. BMW build quality was well known by that point and even a basic late model 518 with power steering and the optional five speed box was a pleasant thing to drive. The late 520’s with electronic ignition were very smooth and quite punchy, the 525 was a bit lost and the 528i and 535i cars were serious cars for the keen driver. Most E12’s were built in the Dingolfing factory which is around 40 miles North of Munich, with the earliest 520 cars being built in the Milbertshofen plant on the Munich ring road.


The 14 inch Mahle BBS Wheel as fitted to E12, E24 and E28

The E12 was also built in some numbers in South Africa however with production beginning at the Rosslyn plant . BMW’s main factories in Germany supplied CKD kits (CKD means Completely Knocked Down, or a kit of parts) to be assembled there. This was to solve the high import taxes in South Africa as well as providing employment. Once the E12 ceased production in Germany in 1981, the body presses were shipped to South Africa where the E12 continued in production until September 1985. Some E28 parts such as the dashboard were used to update the car which was known as the E12/8.

As well as South Africa, BMW also set up CKD assembly facilities in Thailand (Bangkok), Uruguay in South America, Portugal and Indonesia to build E12’s and other BMW’s for local markets.

The E12 in The USA

Building cars in the USA in the seventies was a hard business due to very strict emissions and safety laws. Laden with emissions equipment and massive impact absorbing bumpers, previously proud chariots now needed 5 or 6 litres to get perhaps 200 bhp

BMW had done well with the E3 saloon (the Bavaria) in the US but the E12 5 Series was not imported until 1975. Production of the USA-only 530i began in September 1974 and ran until August 1978 when it was replaced by the 528i.

Basis of the 530i was a 525 saloon complete with solid brake discs all round (upgraded to vented fronts in September 1976 as part of the E12 facelift) and M30 running gear. Because of the extra emissions equipment and the detrimental effect on power, BMW chose to use the 3.0 engine to give it a fighting chance. To get it past the emissions regulations though, BMW went about it in a rather odd way. Rather than use catalytic converters, they chose instead to use thermal reactors so that the car could run on leaded petrol.

These are basically rather crude catalytic converters that are integral with the exhaust manifolds, and they run very hot. To make them even hotter, the ignition timing was retarded, but saved from overheating and detonation by using a richer than normal fuel mixture. This was supplied by a very strange, almost ‘prototype’ version on Bosch L Jetronic - even BMW’s own parts system doesn’t list the full pre September 1976 system.

As a result of the emissions modifications, the 530i was nothing like a European 528 with lethargic town performance and shocking urban fuel consumption of 12 mpg EPA. Original cars were ‘fifty state’ and later ones were 49 state with the California market cars the worst of the lot. The heat from the thermal reactors caused cylinder head cracking problems and whilst it fared okay in new car road tests, the 530i gained itself a less than glowing reputation.

From July 1975, the old Borg Warner Model 65 - never a particularly great unit in the E12 - was replaced by the new ZF 3HP22 that was a huge improvement. The September 1976 facelift was another step in the right direction with the revised L Jetronic engine from the 630CSi, ZF3HP22 automatic option and vented front brakes. For 1978, the 20 spoke alloy wheels were made standard along with air conditioning, electric windows and power steering.

In Autumn 1978, the 528i replaced the 530i. Gone were the awful thermal reactors and exhaust gas re-circulation and in came a three way catalytic converter with lambda control. This 8.2:1 compression engine gave 169 bhp as well as decent fuel economy. The big bumpers remained but the 528i could run on unleaded fuel and all in all, the car was a huge improvement.


USA 530i emissions equipment (BMWAG)


USA 530i emissions equipment (BMWAG)

These days, the E12’s are a pretty rare sight in America despite so many being sold - BMW built 27,870 530i’s and a lot more 528i’s. The problems in old age are just the same as with any other E12, although cars that have lived in hot climates at least won’t be rusty.

The 530i engine was and is a pain, and very few (if any) new parts are available for the emissions equipment - depending of course on where you live, ripping it all out and replacing it with 528i equipment is always the best course of action.


The last European E12 was built at Dingolfing in June 1981 which, at the time of writing, is just over 31 years ago. These were a tremendously well made car - solid, strongly built, impeccably finished and probably better than the Mercedes 115 series. But time and rust have no respect for a badge and you’ll be lucky to find an E12 that’s never seen the hot end of a welder’s torch.

BMW built the bodies well from good steel and they were painted and rust-proofed to the highest standards of the day - but that excluded wax injection into box sections and galvanising, neither of which were very common. Porsche tried galvanising with mixed results and Jaguar’s much vaunted wax injection didn’t stop them from rusting to bits in 10 years so overall, BMW had it about right.


Are you sure you want an E12? Most things the E12 does are done better by the later E28 which looks very similar and which is far more common. The E28 has a better ride and noise suppression, taller final drives and either five speed manuals four speed auto-boxes. An E28 still feels relatively modern and practical to drive and the E12 feels old. But for all that, an E12 makes a great ‘hobby’ car, something to tinker about with and use on the weekends and a nice one is now a bit of a head turner. Just be prepared to either get your hands dirty fixing and improving it, or pay someone else! To be fair, that’s the same remit with all three generations of 5 Series we’re covering but the E12 is more of a challenge because it’s older and parts are harder to find.

The E12 is also a seventies design so you’re into funny old electrics without printed circuit boards and mechanical speedo cables - there’s nothing advanced about an E12.


The really sought after E12 is the M535i, and rightly so. It’s a proper old school BMW - fast, raucous and in the wrong hands, a bit dangerous as well with a bite every bit as sharp as an old 911. The trouble is, they rust just the same as any other E12 and the vast majority were very well used and abused with the result that very few remain in nice condition. Values have yet to take off and so it’s not yet been worthwhile to restore a rough one although a few enthusiasts have carried out some lovely restorations.

Like all E12’s, BMW still supply a huge amount of parts such as panels and some trim, and most mechanical parts are available. The yellow Bilstein dampers are in fluctuating supply and when BMW have none in stock, you either wait until Mobile Tradition get Bilstein to make some more or you hunt around - be aware that the pre May 1982 6 Series is based on an E12 platform and you’ll find the Bilstein B6 and B8 dampers for such a 6 Series will do the job - when available.

These cars also used the original 635CSi 3453 cc engine with a separate distributor and Bosch L Jetronic injection - first generation with the big heavy black ECU. Most of these engines are tired out and need a rebuild, and the later 3430 cc unit introduced for the second generation 635CSi in May 1982 is a bit of a job to fit requiring you to fit a non Motronic camshaft and front timing cover. Used M535i parts are fairly easy to come by because the majority of these cars were broken up due to accidents and rust.

528 and 528i

Before the M535i came along, these were the Top Dog in fast saloons. Whilst a 3.0 Granada wheezed along on a supposed 138 bhp, these had 170 or 177 bhp and even today, a good one is a lively old thing.

Many were automatics with the old 3 speed ZF and whilst they’re quick off the mark, they’re nothing like as good as the four speed manual or the mega rare 5 speed.

Like any E12, there are now very few left and any E12 that’s lasted this long should have been looked after.

Like the 535i, these have the twin servo brakes that require caution because they are an old and complex system with a lot of bits to go wrong. But of the E12’s, the 528i is the one to look out for.


These were always in no mans land. They were pleasant to drive but with 150 bhp, were never road rockets. Most survivors are the post September 1976 facelift cars with that damned Solex 4A1 carb which is a real piece of work, and the post 9/76 cylinder heads were known to crack on these and the 528.


The 2494 cc M30 engine is the smoothest of all the M30 series though, and anyone used to modern cars will like the crisp throttle response, the light gearchange or the noticeable upward gear changes of the ZF 3HP autobox. Now very rare because they weren’t great sellers when new, a nice 525 is still a pleasant old car to cruise around in.

The 520’s.

The four cylinder cars aren’t quite extinct, but there are very, very few left - I’d be surprised if there are ten left on the road in the UK although they are more common in mainland Europe. The 520i was dropped for the UK market in 1977, but continued until June 1979 in some European markets.

The carburettor versions are somewhat leisurely, and like the fuel injection 520i, is in dire need of either a five speed gearbox or a taller ratio final drive from a 525. With skinny 175 tyres and soft suspension they really do feel old but if you accept it for what it is, they’re pleasant and slightly comedic.

Like a W115 Mercedes, an E12 520 is a car for cruising, not getting anywhere in a hurry. Carburettor parts aren’t easy to come by for the 520, and the Kugelfischer injection for the 520i requires specialist knowledge (or a good brain for mechanics and a manual) to set up, although good used parts like pumps and injectors aren’t silly expensive.

Of the 520’s the one to have is the six cylinder. They’re not much quicker but the two litre straight six is a lovely sounding engine when on song and a good uptogether example drives well.


You’ve got to be keen, and you’ve got to really want an E12. With just 90 bhp to push it along, the 518 is a slow car which desperately needs a five speed gearbox to make it useable - without this, they are just too revvy at speed. 518’s also make do without power steering (as do most 520’s). As a result of being so underpowered, most are pretty tired now but on the other had, good 1766 cc carburettor engines still seem to be cheap and plentiful.

Like the 520 and 525, you need to buy a 518 on condition. Forget about restoring a rough one as nobody will thank you for it, but bought in nice condition at the right price, a 518 could be worthwhile.


The E12 was very well made, but they’re old now so you need to know what to look for, what’s easily and cheaply fixable and what’s going to be a nightmare. Here’s the low down...

E12’s were never rust buckets but anything made out of mild steel will rust eventually. Front wings rust well, and they rust along the top along the horizontal surface, at the front adjacent to the headlights and down the back seam and at the bottom where the wing wraps over the sill. BMW still supply new wings and you might just find some unused pattern wings somewhere. They are bolt on and easy enough to fit although undoing the bumper to wing bolts can be a real pain.

The front panel can rot at the bottom of the valance, and the chassis legs need a good prod with a stout screwdriver as well. The inner wings aren’t too prone, but you’ll need to jack the car up at the front and have a good poke at the ‘rifle butt’ inner wing reinforcing panels. The bonnet lasts well but a line of rust along the lower edge means there’s rot bursting out on the seam where the bonnet skin wraps over the frame.

The bonnet is pretty much scrap at this point as unless you do some very skilled metal work, the rust will always be in there and always come back. Good used bonnets are not easy to find, especially pre facelift cars where there are two types for four and six cylinder cars.

Doors like to rust at the front, both on the frame and where the skin folds over. They also rust along the bottom as well, but later E28 doors can be adapted to fit if a mint E12 door can’t be found. Rust also finds its way into the scuttle panel under the screen and is a difficult repair. Moving back, the rear arches are a rot hot spot and an expensive repair because to do it right, you need to weld in repair section - E28 arches can be adapted if E12 ones can’t be found. The rear valances aren’t too bad on later cars, but early ones (pre facelift) are hard to find. Boot lids very rarely rust, and used ones aren’t too hard to find.

Structural rust used to be the death knell, but as long as it’s not falling to bits and the outer shell of the car is okay, you can get sills replaced and floor sections welded in. Check the entire length of the sills, the front floorpans, the floor to sill joint and the rear inner sill by the rear axle beam mounts. M535i’s had a problem where ‘spirited’ driving would fracture the floor where the differential rear mount bolts in.

BMW used to make a repair/reinforcing panel for this, but now you’ll have to make your own. It’s not unknown for a 528i to need this repair but it’s pretty rare and the others haven’t got enough power to do it. The rear turrets can also rot where the rear struts fit and repair is a fairly simple welding job - it’s double skinned in places though.

Good chrome is important on an E12 because although BMW can still supply new bumper sections, they’re pretty expensive - you can easily spend £500 building a new bumper from parts. The steel is good and thick though so they can be rechromed if it works out cheaper. Rear lights had removable lenses and there are plenty of good used ones about, but headlights are very rare in good secondhand condition. Again, they are available new from BMW, and the surprise is that they’re not that expensive. These are inserts which fit into the cupped light holders and the lights come out once you’ve removed the outer ring.


Typical patched-up E12 Inner Wing


Rear Arch Corrosion Behind Bumper Corner


E12 Inner Wing Rot - caused by moisture in the double skinning


The same area after Tony Chamberlain has repaired it properly

Like the body, old age is the enemy of the engines and most of them have done a few miles now. The three engine series used are the M10 four cylinder, the M60 six cylinder in the 520 and the M30 in the three engine series used are the M10 four cylinder, the M60 six cylinder in the 520 and the M30 in the 525, 528, 528i and M535L


Typical E12 inner wing rust, and previous nasty repair job

Starting with the M10, this is an iron block/alloy head single cam unit that goes back to 1962 and the BMW 1500. The 2 litre first appeared in 1965 in the 2000 Coupe and the 1966 2000 saloon, and the 1766 cc unit goes back to 1963. It was already an old engine when it appeared in the 5 Series but it was such a good unit and ahead of its time that it lasted until 1988.

The oil light needs to go out pretty much from the moment it starts. An oil light that lingers for a few seconds could be tiredness in the crank bearings - check for horrible black smelly oil and harshness once it’s hot.

An oil light that takes maybe ten seconds to go out on an engine that sounds nice when it’s gone out could be a blown oil seal where the oil pick up pipe meets either the oil pump or the block. It’s not an expensive repair, but it means removing the crank pulley, dropping the sump and removing the upper and lower timing covers. A good days work and a few quid for gaskets, plus a good opportunity to clean the sump pan out. A noisy top end on an old M10 is general cam and rocker wear and is caused by neglect. Given 6000 mile oil changes, yearly valve clearance checks and ensuring the spray bar oil holes are clear and the banjo securing bolts are tight, the cam and rockers will do 250,000 miles if not more. Changing a cam on an M10 or M30 is unfortunately a cylinder head off job.

Post September 1980 cars went from a Duplex to a single row timing chain, and it made a difference to chain life on the 518, causing wear to the camshaft sprocket and they can wear so badly that the chain eats down into the sprocket and the tensioner is no longer able to take up the chain slack. Fitting a new sprocket is quite an easy job though.

Tired and rattly 518 engines are best removed and thrown away. The 1766 cc M10 was used until 1988 in the E30 316 and there are still plenty of decent engines from these about for next to nothing. They really are unwanted so rather than spending money rebuilding a worn out engine, it makes far more sense to just replace it with a nice used one.

The same can’t be said for the 4 cylinder 520, because once they were replaced by the six in 1977, that was the end of them. You might be lucky and find a decent one in a terminally rusty 2002 (which needs to be a 1973 or later car), but the chances of that are very slim - this is one engine which will need to be stripped and rebuilt when it’s worn out.

E12 518’s and 520’s used various different carbs as well. The twin choke Solex used on the 518 is pretty reliable and they are easily stripped and overhauled as long as the throttle spindle wear isn’t too bad. If you have real aggro with the twin Strombergs on the 520, you could consider fitting a different set up - either conventional 175CD units as fitted to Triumphs or SU’s. You could in theory fit a twin choke Solex from a 2002 or early 320 but you would lose about 10 bhp which is important. So if a 520 doesn’t run very well, budget for some possibly expensive carburettor work.

The M60 used in the later 520 is a nice engine when it’s right. These engines were later recoded M20 for use in the 1983 model E28 and E30 cars and they’re generally reliable. They were known for cracking heads though, and it’s fairly safe to assume that any head that’s lasted this long will be okay. Actual head gasket failure is rare on the M60 and any mixing of oil and water will be the dreaded crack under the camshaft from the water gallery upwards. All BMW engines have a date cast into the side of the head so you’re looking for a two digit number in a circle - ‘78’ would indicate that it was cast in 1978 for example.

All E12 520 cars with the M60 engine will have the original type cambelt with square teeth, and these are now available from BMW. That apart, the 520 M60 engine is pretty good, but it’s blighted with the Solex 4A1 carburettor. These are a nightmare of vacuum pipes, solenoids and flaps, and when they go wrong, they really go wrong. Many cars were converted to run a 38DGAS Ford 3 litre V6 carburettor which isn’t a bad conversion at all. It should start straight away from cold, idle at 1200 and slowly drop to around 750 - 800 as it warms up. If it chugs like a steam train and the idle is variable, then the carb is in trouble.

The M30 engine first appeared in 1968, and it’s a bit of a classic. The early E12 versions used what was basically an E3 engine complete with the twin Solex twin choke INAT carbs but these are rare now. From late 1976 both the cylinder head and the carburation were revised to clean up the emissions, and introduced a whole set of problems. The 4A1 Solex needs no introduction as a truly awful carburettor - with this fitted the M30 made no more power than before and used more fuel. The later head casting was also prone to cracking and many cars either had new cylinder heads or the existing castings welded up at as low as 50,000 miles. M30 heads are also prone to alloy corrosion if they do not get yearly anti freeze changes - the alloy used in these engines does not like being left in old stewing anti freeze, and particles of corroded alloy will lodge in the base of the radiator and cause overheating.

Fuel injection engines may have had a lifetime of abuse, but they can be replaced with later E28 units with mods we’ll go into later. The L Jetronic system is in its first generation here - it goes back to 1976 and the 3.0Si and 633CSi cars. It’s a reliable system but you need to make sure it runs nicely as it should. There aren’t any particular weak spots but the parts are unique to this early system.

Exhausts are available still from BMW - at a price. However, with some work to reshape the tailpipes and repositioning the hanger brackets, E28 systems can be adapted to fit.

The suspension was quite advanced for it’s time but is basic and simple now. At the back you’ve got heavily built trailing arms on a girder like axle beam with bolted on end bushes. Rear dampers rarely wear out and they bolt into a bracket on top of the trailing arm. At the front, there is a McPherson strut with a simple location setup with an anti roll bar at the front and track control arms. Front shocks are a common casualty on any old 5 Series and the E12 is no different. They’re still available new although the yellow Bilsteins used on Sport suspension cars and the M535i can be hard to find and are often on back order from BMW. A few words of caution on changing these later on. Power steering was standard on the 528, 528i and M535i, optional (but common) on the 525 and rare on the four cylinder cars. The steering boxes last well enough and any free play at the wheel will be the column adjuster nut needing a tighten, a bit of play in the box or a worn ball joint in either the centre tie rod or either of the track rods.

Without the Bilstein sport suspension, the E12 will feel quite soft even when in good condition. If it feels really wandery or the front end rises and falls like a ship at sea, then it’s going to need a bit of work.

Apart from the 1978-81 518, 520 and 525 cars, the RHD E12’s used the twin servo system inherited from the RHD E3 saloon. BMW used this system because there wasn’t room for a normal vacuum servo on the bulkhead with the steering column there, so they came up with this idea. When it was new, it was great, but now it’s old, it’s a liability. You have a master cylinder on the bulkhead operated directly by the pedal, and this feeds fluid into two more hydraulic cylinders, each with a vacuum servo and each feeding two opposed wheels because it’s a split hydraulic system.

The problem is that without knowing it, one of the remote cylinders can be leaking brake fluid into a servo body and the first you know of it is when you’ve got no brakes. So make very sure the brake fluid level warning light works. New servos are just not available, but like some 2002 owners have done, you can adapt two new Lucas Girling servos to fit. You can also convert to the later post 1978 system.

E12’s have good old fashioned multi piston calipers and it should pull up good and straight. Dragging brakes indicate failing flexy brake hoses, and any E12 with the originals must have them replaced.

What about the electrics? Apart from the occasional sunroof and electric windows, these were very basic in this department. There is no ABS, no circuit boards for instruments, no on board computer. Many E12’s have a funny habit of the temperature gauge needle flicking up a few degrees when the heater blower fan is turned on. They just do that - nothing to worry about as such.

Any E12 in good condition is going to need some work to keep it that way. Rust-proofing fluids like Waxoyl and Dinitrol are good. Keeping the car as clean as possible underneath is the best way



The M10 powered the 518, 520 and 520i. It’s a great engine capable of a lot of miles but they are of course old now and most have done those miles. The main problems are low oil pressure, camshaft wear and general tiredness, and many will be in need of a rebuild.

The pre 1976 cars (9/75 build) used the 2002 series engines, those made after that used E21 3 Series units. Around 1979, the M10 distributors were altered to run backwards - BMW revised the cam so that the drive gear worked the other way....nobody knows why. What that means is, you must use the right camshaft during a top end rebuild if you use a new 2002 cam, you will also need a 2002 distributor to go with it. You cannot just swap the plug leads around, because if the distributor turns the wrong way, the advance weights will not centrifuge outwards and the car will have dismal performance.

The 2 litre M10’s used in the 520 and 520i used a forged steel crank and the 518 did not. That doesn’t make much of a difference in real life, but if they need a regrind the 2 litre cranks may need to be heat treated if seriously reground and the 1.8 crank is best thrown in the skip and replaced with a good used one as they are very plentiful.