Ignition System Specifications (BMW 5 Series E12)

The ignition system is contact, battery ignition. Includes an ignition distributor, ignition coil, spark plugs and low and high voltage wires.

Since model year 1980 on BMW "525", "528i", "535i", from the 1981 model year on the "518" and from the 1982 model year on all BMW 5-series models, a contactless TSZ ignition system with adjustment of the ignition advance and retard angle by a vacuum regulator of the ignition distributor sensor began to be installed.

The order of operation of the cylinders:

• "518", "520" and "520i" 1-3-4-2;
• "525" and "528": 1-5-3-6-2-4.

Battery

The battery is located in the front left part of the engine compartment. The negative terminal of the battery is connected to the vehicle ground.

Nominal voltage, V 12.

Nominal capacity. Ah:

• "518": 36;
• "520", "520i": 55.

Ignition coil

"518", "520" and "520i"

Brand and type: Bosch K12 V.

Average power consumption at 1000 rpm, W: 19.

Ignition voltage, V: 15000.

"525" and "528"

Brand and type: Bosch KW 12 V.

Average power consumption at 1000 rpm, W: 20.

Primary winding resistance at 20°C, Ohm: 1.7-2.1.

Ignition voltage. V: 14000-16000.

Since the 1978 model year, the Bosch ignition coil, catalog no. 0 221 119 017, type KW 12 V, was used on the BMW "525" and "528" only with an additional resistance of 0.9±0.005 Ohm.

The BMW "5281" used a Bosch ignition coil, catalog No. Ne 0 221 122 010, type KW 12 V.

Primary winding resistance, Ohm: 0.4.

Additional resistance Bosch, Ohm: 0.4-0.6.

Beginning with the 1980 model year, the 525 used the 525i ignition coil kit.



The "518" was equipped with a Bosch ignition coil, part number 0 221 119 035.

Primary winding resistance. Ohm: 2.9-3.4.

The additional resistance remained unchanged.

Since the 1981 model year, the "518" was equipped with a Bosch ignition coil, part number 0 221 112 319.

Primary winding resistance. Ohm: 0.82.

From model year 1982 onwards, all models were equipped with a Bosch ignition coil, part number 0 221 122 319 (see above).

Transistor ignition system switch TSZ

Brand and catalog Nb: Bosch 0 227 100 008.

Nominal voltage, V: 12.

Operating voltage, V: 6-15.

When working on a transistor ignition system, be sure to turn off the ignition.

Warning: Do not use ignition coils designed for transistorized ignition systems (TSZ) in contact ignition systems.

Ignition coils for contact ignition systems have the Bosch catalogue number 0 221 119 016, for transistor ignition systems - 0 221 122 607.

If the ignition coils are mixed up, the breaker contacts can quickly burn out, which can cause ignition failures and difficult cold starting of the engine.

Since model year 1980 on BMW "525", "528i" and "535i" was equipped with a Bosch transistor ignition system, catalog number 0 227 100 025.

From the 1981 model year onwards, the "518" and from the 1982 model year onwards, all BMW 5 Series models were equipped with a TSZ Bosch transistor ignition system, part number 0 227 100 111.

"520", "520i" with 6-cylinder engines

Brand and catalog number of ignition coil: Bosch 0 221 122 010.

Primary winding resistance. Ohm: 0.4.



Secondary winding resistance. Ohm: 9.5.

Part number of additional resistor: 0 227 900 101.

Nominal resistance of the additional resistor, Ohm: 0.4 and 0.6.

Since model year 1982, a Bosch ignition coil, part number 0 221 122 319, has been installed.

Primary winding resistance, Ohm: 0.82.

Secondary winding resistance. Ohm: 8.25.

TSZ Transistor Ignition System Switch

Catalog number: 0 227 100 025.

Distributor

Bosch ignition distributor with built-in rotor centrifugal shaft speed limiter (6600 rpm) driven by a helical gear mounted on the end of the camshaft
Catalogue numbers of ignition distributors:

• "518": 0 231 180 004;
• "520": 0 231 180 013*;
• "520" with automatic transmission, "520i": 0 231 151 009** (JF D4);
• "525": 0 231 169 007 (JF UR 6);
• "528": 0 231 309 005 (JF UR 6R).

* From chassis numbers 3 731 732 BMW 520, 3 805 345 BMW 520 A.

** On "520" models with automatic transmission, from December 1975, instead of ignition distributor No.0 231 151 008, which has the same characteristics.

The ignition timing is set by matching the marks on the timing mechanism drive cover and on the crankshaft pulley. In addition, there is a mark or a steel ball with a diameter of 4 mm (pressed into the flywheel) to set the ignition timing using a stroboscope. The mark on the flywheel is visible through the hole in the clutch housing.

Characteristics of ignition distributors

Initial ignition timing angle when set on a non-running engine

• "518": 3° before TDC;
• "520": 8° before TDC;
• "520i": installation at TDC;
• "525", "528": installation at TDC.

Initial ignition timing angle when setting with a stroboscope

• "518": 25° at 1400 rpm;
• "520": 25° at 1800 rpm;
• "520" with automatic transmission, "520i": 25° at 2400;
• "525", "528": 22° at 1700±50 rpm.

On BMW "525" and "528" with Pierburg 4A1 carburetor, a Bosch ignition distributor was installed, catalog No.0 231 309 006 (PFU0 6).

The ignition distributor rotor had a Bosch speed limiter, part number 1 234 332 196, with a 5 kOhm interference suppression resistor.

The "528i" was equipped with a Bosch PGFUD ignition distributor sensor with a contactless sensor, catalog number 0 231 181 017 (JFUDA).

Since the 1980 model year, the following types of distributors or ignition distributor sensors have been installed:

• "518" and "518A": Bosch 0 237 181 017;
• "525" and "525A": Bosch 0 237 302 010;
• "528i" and "528": Bosch 0 23 302 014 and 019;
• "525i" Bosch 0 237 302 008.

Corresponding types of distributor rotors and Bosch ignition distributor sensors:

• "518" and "518A": 1 234 332 208 with 5 kOhm TSZ noise suppression resistor;
• "528i": no changes;
• "535i": 1 234 332 227 with 5 kOhm TSZ noise suppression resistor.

Since the 1981 model year, the BMW "518" was equipped with a Bosch ignition distributor sensor, catalog no. 0 237 011 004, with a Bosch rotor, catalog no. 1 234 332 297 and a TSZ interference suppression resistor of 1 kOhm.

Since the 1982 model year, the BMW "525i/E28" and "528i/E28" were equipped with a Bosch ignition distributor sensor, part number 0 237 302 026, with a 1 kOhm interference suppression resistor, part number 1 234 332 196.

Characteristics of distributors or ignition distributor sensors

Centrifugal ignition timing adjustment

It is installed using a stroboscope with a phase shift, with the vacuum hoses disconnected, on a warm engine. The stroboscope is directed at the TDC (OT) mark on the crankshaft pulley.

Characteristics of the vacuum ignition timing regulator

"520" and "520i" with 6-cylinder engines

Bosch ignition distributor, catalog no. 0 237 301 011.



Ignition distributor rotor, catalog No.1 234 332 196, with interference suppression resistor TSZ with a resistance of 5^+20%_-10% kOhm.

Since the 1982 model year, a Bosch ignition distributor sensor, catalog 0 237 302, was installed, with a rotor, catalog No.1 234 332 313 with a noise suppression resistor with a resistance of 1^+20%_-10% kOhm.

Initial ignition advance angle before TDC, deg.: 11.

TDC sensor

Since model year 1977 on BMW "525", "528" and "528i" a Bosch TDC sensor was installed, catalog Nb 0 335 541 002.

Resistance when measured between terminals, Ohm: 80±10.

Gap between the sensor and the mounting pin, mm: 0.2-2.0.

Spark plugs

Thread of the screw-in part M14 x 125.

Brand and type of spark plugs: Bosch W 175 T 30 (W 145 T 30), Vegi 175/14/3 A (145/14/3 A), Champion N 9 Y (N 11 Y)*.

* With a speed limit of 80-100 km/h for "520" and "520i".

"518": Vegi 200/14/3 A, Bosch W 200 T 30, Champion N 8 Y.

Gap between electrodes, mm: 0.6+0.1.

Spark plugs

Since the 1978 model year, the following types of spark plugs were installed on the BMW "525" and "528": Beru 145/14/ZA (0.60); Bosch W145 T 30 (0.65); Champion N 10 Y (0.60). On "528i": Vega 175/14/ FOR (0.60); Bosch W175T 30 (0,65); Champion N 10 Y (0.60). The gap between the electrodes in mm is given in brackets.

Since the 1980 model year, all models were equipped with the following types of spark plugs: Bosch W 145 T 30; Vegi 145/14/ZA; Champion N 10 Y (except for models with automatic transmission).

Gap between electrodes, mm: 0.6+0.1.

"520" and "5201" with 6-cylinder engines

Brand and type: Bosch W 145 T 30; Vegi 145/14/ZA; Champion N 10 Y (only on cars with automatic transmission).

Gap between electrodes, mm: 0.6+0.1.