Tuesday, November 20, 2012



M30 engine (6-cylinder), available on the 525i, 528i, 535i, are the most reliable. If they were properly maintained, you should not consume any oil, even after 300,000 km. Has distribution through chain. Cylinder head needs some help after approx. 500,000 km (seals new valve rectification offices, distribution chain, and so on), but gear can withstand engine block in good condition until at 800,000 Km. Still have antiquated architecture and electronic management is also primitive, with negative effects on power consumption litter of gasoline.

To watch:

- Main problem: camshaft wear. At M30, camshaft lubrication is poor. The smallest problem Circuit lubrication can lead to rapid wear of the cam. Check 12mm bolts attaching the oil platform are properly tightened. Preferably new model with a milling head bolt circle. Check that no pins are worn (not hang nail when they go over the top);

- Like cylinder head gasket changed after approx. 15 .. 18. It does not cost much, but it's laborious. Check the spark plug color. If one (or more) are questionable clean, as would have been in a steam bath, suspected cylinder head gasket problems, or even holes in the cylinder head.

- M30 engine oil should not drink and should not fight. If you see blue smoke in the exhaust is very serious;

- Not worrying if it starts to "Key quarter," but it's not normal to start after more than 3 .. 4 seconds of actuation of the starter;

- Distribution of M30 is noisy. In addition, injectors loony lot. A M30, at idle, it sounds almost Diesel;

- With the engine idling, remove the oil dipstick must cause a noticeable worsening. Otherwise, false means that the engine draw air somewhere;

- Rubber hoses that feed fuel rail must be replaced at about 100,000 km. Check especially rubber hose from the ramp to the cold start injector. This gives the first and, if cracked, can cause a fire;

- M30 engine because of its weight, its supports must be replaced at least every 5 years. Otherwise, you risk becoming too elastic, and the powerful brakes tends to push the radiator fan.

M20 engine (6-cylinder), available on the 520i, 525e, are not as reliable as the M30, but not far from it. Instead, have a more modern design, electronics better and easier to maintain. Recognize them easily by the fact that they cast belt.

To watch:

- Change the belt right after you bought the car, unless you are 100% sure you know when it was changed last time.

M10 engine (4-cylinder) are available on 518 / 518i. Distribution chain. Almost as reliable as the M30 (basically derived from M10 to M30, which were added 2 cylinders).

Given the age engines, change oil filter max. 5000 km (mineral oil / semisynthetic) or 8000 km (synthetic oil), if you want to keep the car. Because engines are designed in the 60's .. 70's internal tolerances are larger and rather more viscous oils.

If you use mineral oil, look for a high quality, 20W50 10W40 in summer and winter. If you use synthetic oil, do not fall below 10W40.

M30 engines feel very good with Castrol RS 10W60 synthetic oil (that's right, very expensive).


Avoid automatic gearbox versions. Automatic transmission on the E28 gives up to 200,000 kilometres.

Sports manual gearbox (those that I step down, then he mated with III and IV to V) have direct and stage V sockets are the most fun to drive, but not crazy about the reliability. Most robust Getrag manual gearbox are 260/6, with direct plug stage IVa and V of overdrive. Recognize them by the fact that they cast clutch housing (Primary) and have longitudinal cooling fins on the bottom of the box.

All boxes Getrag, after 100,000 km, flowing back to the oil seal. Also, all come harder in speed when oil is cold box. Race exchanger is quite long and does not favor rapid changes of speed.

In boxes, just put mineral oil API GL4. GL5 oils contain sulphur and attack synchrony.

Clutches hold well over time. Are actuated hydraulic cylinders so check state master / slave. M30 engines, it is normal for the clutch to require slightly higher down force than a clutch 3 Series E30. There are rare cases in which the support plate clutch master cylinder crack and be welded.

Shaft, especially on models with engines larger than 2.8l, catch couplings game, especially at the rear (the differential). Unfortunately, quality car couplings disappointing, and almost all were playing After 150,000 km, especially on models with powerful engines.

Differentials are strong, but their pads checked. Top of the range models have LSD differential. Differential housings are two types of "small" (has both caps, filling and emptying, back cover) and "large" (filler cap is on the back cover, the drain on the left side). Differential "small" is interchangeable with that of the E30 (just take the back cover and worldwide flanges on the E28) and gives you the opportunity to choose from a wide range of reports. Differential "high" was installed on top of the range model and is less common, so hard to find other reports.