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Fluid level checks BMW 3-Series 2008 - 2012 Diesel 325d - 3.0

OnDemand step-by-step maintenance & repair BETA

BMW 3-Series 2008 - 2012  | 325d - 3.0 Fluid level checks

  • time 5 to 30 minutes
  • difficulty 1

Underbonnet check points

2.0 litre petrol (N43) engine A Engine oil filler cap B Coolant expansion tank C Brake and clutch fluid reservoir (under the plastic cover) D Screenwasher fluid reservoir
2.0 litre diesel (N47T) engine A Engine oil level dipstick B Engine oil filler cap C Coolant expansion tank D Brake and clutch fluid reservoir (under the plastic cover) E Screenwasher fluid reservoir

Engine oil level

1 • Make sure that the car is on level ground.
2 • Check the oil level before the car is driven, or at least 5 minutes after the engine has been switched off.
HINT: If the oil is checked immediately after driving the vehicle, some of the oil will remain in the upper engine components, resulting in an inaccurate reading on the dipstick.

The correct oil

3 Modern engines place great demands on their oil. It is very important that the correct oil for your car is used.
Engine oil grade:
  Petrol engines BMW Long-life 01, 01-FE or 04. SAE 0W-40 or SAE 5W-30 (fully synthetic)
  Diesel engines:
    M57TU 6-cylinder engines BMW Long-life 01 or 04. SAE 0W-40 or SAE 5W-30 (fully synthetic). The lower viscosity oil is recommended in countries where the outside temperature frequently falls below -20° C
    N47 (4-cylinder) and N57 (6-cylinder) engines BMW Long-life 04. Note: This oil is specifically designed for engines with a particulate filter. SAE 0W-40 or SAE 5W-30 (fully synthetic)

Car care

4 • If you have to add oil frequently, you should check whether you have any oil leaks. Remove the engine undershield, place some clean paper under the car overnight, and check for stains in the morning. If there are no leaks, the engine may be burning oil, or the oil may only be leaking when the engine is running. Note that petrol models, and some 4-cylinder diesel engines, do not have a traditional oil level dipstick. Instead the level is shown on the instrument cluster. On other engines, the oil level is checked using a traditional dipstick.

Models without a dipstick

5 • Start the engine, lightly push the button on the indicator stalk up or down until the word OIL is shown in the instrument cluster display. Press the button on the end of the indicator stalk and the oil level will be displayed. If necessary, stop the engine and add engine oil until the level is correct. Refer to the owners handbook for details of the electronic oil level monitor.

Models with a dipstick

6 • Always maintain the level between the upper and lower dipstick marks, shown in photo 3. If the level is too low, severe engine damage may occur. Oil seal failure may result if the engine is overfilled by adding too much oil.
The dipstick top is often brightly-coloured for easy identification (see Underbonnet check points for exact location). Withdraw the dipstick.
Using a clean rag or paper towel remove all oil from the dipstick. Insert the clean dipstick into the tube as far as it will go, then withdraw it again.
Note the oil level on the end of the dipstick, which should be between the upper maximum mark (1) and lower minimum mark (2). Approximately 1.0 litre of oil will raise the level from the lower mark to the upper mark.
Oil is added through the filler cap. Unscrew the cap and top‑up the level; a funnel may help to reduce spillage. Add the oil slowly, checking the level on the dipstick often. Don’t overfill (see Car care).
- Close + Open

Engine oil and filter change

1 Frequent oil and filter changes are the most important preventative maintenance work which can be undertaken by the DIY owner. As engine oil ages, it becomes diluted and contaminated, which leads to premature engine wear.
2 Before starting this procedure, gather together all the necessary tools and materials. Also make sure you have plenty of clean rags and newspapers handy, to mop-up any spills. Ideally, the engine oil should be warm, as it will drain better, and more built-up sludge will be removed with it. Take care, however, not to touch the exhaust or any other hot parts of the engine when working under the car. To avoid any possibility of scalding, and to protect yourself from possible skin irritants and other harmful contaminants in used engine oils, it is advisable to wear gloves. Access to the underside of the car will be improved if it can be raised on a lift, driven onto ramps, or jacked up and supported on axle stands. Whichever method is chosen, make sure the car remains level, or if it is at an angle, so that the drain plug is at the lowest point. Where necessary remove the undershield from under the engine. On vehicles equipped with front reinforcement plate between the front suspension lower control arms, access to the sump plug is via a removable flap in the plate (see illustration) .
Rotate the fastener to access the sump drain plug
3 Working in the engine compartment, locate the oil filter housing on the left-hand side of the engine, in front of the intake manifold. Undo the bolts (M57T2 engines only) and remove the plastic acoustic cover from the top of the engine (see illustrations) .
On M57T2 engines, undo the 2 bolts and lift and pull the plastic cover from the top of the engine. Note the locating lugs at the rear (arrowed)
On N47 and N57 engines, pull up the front edge, and slide the plastic cover forwards
4 Place a wad of rag around the bottom of the oil filter housing to absorb any spilt oil.
5 Using a spanner or socket, unscrew and remove the cover, complete with filter cartridge (see illustration) . The oil will drain from the housing back into the sump as the cover is removed.
Unscrew the cover and remove it complete with filter element
6 Recover the O-rings from the cover.
7 Using a clean rag, wipe the mating faces of the housing and cover.
8 Fit new O-rings to the cover (see illustration) .
On all engines, renew the cover cap O-ring seal. Where applicable, also renew the cover centre O-rings
9 On M57T2 engines, fit the new filter cartridge into the cover (see illustration) . On N47 and N57 engines, fit the new filter element into the filter housing, ensuring the lug on the base of the element aligns with the locating hole in the housing (see illustration) .
Fit the new element to the cover – M57T2 engines
Align the lug on the base of the filter element . . .
12.9c . . . with the locating hole in the housing – N47 and N57 engines
10 Smear a little clean engine oil on the O-rings, refit the cover and tighten it to 25 Nm (18 lbf ft) if using the special filter removal tool, or securely if using a strap wrench.
11 Working under the car, slacken the sump drain plug about half a turn (see illustration 12.2) . Position the draining container under the drain plug, then remove the plug completely. If possible, try to keep the plug pressed into the sump while unscrewing it by hand the last couple of turns. Note that on some models, it will be necessary to rotate the fastener and open the drain plug access flap in the engine undershield.
12 Recover the drain plug sealing ring.
13 Allow some time for the old oil to drain, noting that it may be necessary to reposition the container as the oil flow slows to a trickle.
14 After all the oil has drained, wipe off the drain plug with a clean rag. Renew the plug sealing washer. Clean the area around the drain plug opening, then refit and tighten the plug to the specified torque (see illustration) .
Renew the sump drain plug washer
Engine sump oil drain plug: Nm Ibf ft
  M12 plug 25 18
  M18 plug 35 26
  M22 Plug 60 44
15 Remove the old oil and all tools from under the car, then lower the car to the ground (if applicable).

Models without a dipstick

16 Add a little less than the correct amount of oil to the engine through the oil filler cap orifice, using the correct grade and type of oil. An oil can spout or funnel may help to reduce spillage.
Engine oil quantity:
  4-cylinder engines 5.2 litres
  6-cylinder engines 7.5 litres
Engine oil grade:
  M57TU 6-cylinder engines BMW Long-life 01 or 04. SAE 0W-40 or SAE 5W-30 (fully synthetic). The lower viscosity oil is recommended in countries where the outside temperature frequently falls below -20° C
  N47 (4-cylinder) and N57 (6-cylinder) engines BMW Long-life 04. Note: This oil is specifically designed for engines with a particulate filter. SAE 0W-40 or SAE 5W-30 (fully synthetic)
17 Start the engine and run it for 3 minutes; check for leaks around the oil filter seal and the sump drain plug. Note that there may be a delay of a few seconds before the oil pressure warning light goes out when the engine is first started, as the oil circulates through the engine oil galleries and the new oil filter, before the pressure builds-p.
18 Lightly push the button on the indicator up or down until the work OIL is shown in the instrument cluster display. Press the button on the end of the indicator stalk and the oil level will be displayed. If necessary, stop the engine and add engine oil until the level is correct (see illustration) . Refer to the owners handbook for details of the electronic oil level monitor.
Oil level display in the instrument cluster

Models with a dipstick

19 Remove the dipstick then unscrew the oil filler cap from the cylinder head cover. Fill the engine, using the correct grade and type of oil as described previously in this Section. An oil can spout or funnel may help to reduce spillage. Pour in half the specified quantity of oil first, then wait a few minutes for the oil to run to the sump. Continue adding oil a small quantity at a time until the level is up to the lower mark on the dipstick. Finally, bring the level up to the upper mark on the dipstick. Insert the dipstick, and refit the filler cap.
20 Start the engine and run it for a few minutes; check for leaks around the oil filter seal and the sump drain plug. Note that there may be a delay of a few seconds before the oil pressure warning light goes out when the engine is first started, as the oil circulates through the engine oil galleries and the new oil filter, before the pressure builds-up.
21 Switch off the engine, and wait a few minutes for the oil to settle in the sump once more. With the new oil circulated and the filter completely full, recheck the level on the dipstick, and add more oil as necessary.

All models

22 Dispose of the used engine oil safely.
- Close + Open

Engine oil and filter change

1 Frequent oil and filter changes are the most important preventative maintenance work which can be undertaken by the DIY owner. As engine oil ages, it becomes diluted and contaminated, which leads to premature engine wear.
2 Before starting this procedure, gather together all the necessary tools and materials. Also make sure you have plenty of clean rags and newspapers handy, to mop-up any spills. Ideally, the engine oil should be warm, as it will drain better, and more built-up sludge will be removed with it. Take care, however, not to touch the exhaust or any other hot parts of the engine when working under the car. To avoid any possibility of scalding, and to protect yourself from possible skin irritants and other harmful contaminants in used engine oils, it is advisable to wear gloves. Access to the underside of the car will be improved if it can be raised on a lift, driven onto ramps, or jacked up and supported on axle stands. Whichever method is chosen, make sure the car remains level, or if it is at an angle, so that the drain plug is at the lowest point. Where necessary remove the undershield from under the engine. On vehicles equipped with front reinforcement plate between the front suspension lower control arms, access to the sump plug is via a removable flap in the plate (see illustration) .
Rotate the fastener to access the sump drain plug
3 Working in the engine compartment, locate the oil filter housing on the left-hand side of the engine, in front of the intake manifold. Undo the bolts (M57T2 engines only) and remove the plastic acoustic cover from the top of the engine (see illustrations) .
On M57T2 engines, undo the 2 bolts and lift and pull the plastic cover from the top of the engine. Note the locating lugs at the rear (arrowed)
On N47 and N57 engines, pull up the front edge, and slide the plastic cover forwards
4 Place a wad of rag around the bottom of the oil filter housing to absorb any spilt oil.
5 Using a spanner or socket, unscrew and remove the cover, complete with filter cartridge (see illustration) . The oil will drain from the housing back into the sump as the cover is removed.
Unscrew the cover and remove it complete with filter element
6 Recover the O-rings from the cover.
7 Using a clean rag, wipe the mating faces of the housing and cover.
8 Fit new O-rings to the cover (see illustration) .
On all engines, renew the cover cap O-ring seal. Where applicable, also renew the cover centre O-rings
9 On M57T2 engines, fit the new filter cartridge into the cover (see illustration) . On N47 and N57 engines, fit the new filter element into the filter housing, ensuring the lug on the base of the element aligns with the locating hole in the housing (see illustration) .
Fit the new element to the cover – M57T2 engines
Align the lug on the base of the filter element . . .
12.9c . . . with the locating hole in the housing – N47 and N57 engines
10 Smear a little clean engine oil on the O-rings, refit the cover and tighten it to 25 Nm (18 lbf ft) if using the special filter removal tool, or securely if using a strap wrench.
11 Working under the car, slacken the sump drain plug about half a turn (see illustration 12.2) . Position the draining container under the drain plug, then remove the plug completely. If possible, try to keep the plug pressed into the sump while unscrewing it by hand the last couple of turns. Note that on some models, it will be necessary to rotate the fastener and open the drain plug access flap in the engine undershield.
12 Recover the drain plug sealing ring.
13 Allow some time for the old oil to drain, noting that it may be necessary to reposition the container as the oil flow slows to a trickle.
14 After all the oil has drained, wipe off the drain plug with a clean rag. Renew the plug sealing washer. Clean the area around the drain plug opening, then refit and tighten the plug to the specified torque (see illustration) .
Renew the sump drain plug washer
Engine sump oil drain plug: Nm Ibf ft
  M12 plug 25 18
  M18 plug 35 26
  M22 Plug 60 44
15 Remove the old oil and all tools from under the car, then lower the car to the ground (if applicable).

Models without a dipstick

16 Add a little less than the correct amount of oil to the engine through the oil filler cap orifice, using the correct grade and type of oil. An oil can spout or funnel may help to reduce spillage.
Engine oil quantity:
  4-cylinder engines 5.2 litres
  6-cylinder engines 7.5 litres
Engine oil grade:
  M57TU 6-cylinder engines BMW Long-life 01 or 04. SAE 0W-40 or SAE 5W-30 (fully synthetic). The lower viscosity oil is recommended in countries where the outside temperature frequently falls below -20° C
  N47 (4-cylinder) and N57 (6-cylinder) engines BMW Long-life 04. Note: This oil is specifically designed for engines with a particulate filter. SAE 0W-40 or SAE 5W-30 (fully synthetic)
17 Start the engine and run it for 3 minutes; check for leaks around the oil filter seal and the sump drain plug. Note that there may be a delay of a few seconds before the oil pressure warning light goes out when the engine is first started, as the oil circulates through the engine oil galleries and the new oil filter, before the pressure builds-p.
18 Lightly push the button on the indicator up or down until the work OIL is shown in the instrument cluster display. Press the button on the end of the indicator stalk and the oil level will be displayed. If necessary, stop the engine and add engine oil until the level is correct (see illustration) . Refer to the owners handbook for details of the electronic oil level monitor.
Oil level display in the instrument cluster

Models with a dipstick

19 Remove the dipstick then unscrew the oil filler cap from the cylinder head cover. Fill the engine, using the correct grade and type of oil as described previously in this Section. An oil can spout or funnel may help to reduce spillage. Pour in half the specified quantity of oil first, then wait a few minutes for the oil to run to the sump. Continue adding oil a small quantity at a time until the level is up to the lower mark on the dipstick. Finally, bring the level up to the upper mark on the dipstick. Insert the dipstick, and refit the filler cap.
20 Start the engine and run it for a few minutes; check for leaks around the oil filter seal and the sump drain plug. Note that there may be a delay of a few seconds before the oil pressure warning light goes out when the engine is first started, as the oil circulates through the engine oil galleries and the new oil filter, before the pressure builds-up.
21 Switch off the engine, and wait a few minutes for the oil to settle in the sump once more. With the new oil circulated and the filter completely full, recheck the level on the dipstick, and add more oil as necessary.

All models

22 Dispose of the used engine oil safely.

Coolant level

Warning: Do not attempt to remove the expansion tank pressure cap when the engine is hot, as there is a very great risk of scalding. Do not leave open containers of coolant about, as it is poisonous.

Car Care

7 • With a sealed-type cooling system, adding coolant should not be necessary on a regular basis. If frequent topping-up is required, it is likely there is a leak. Check the radiator, all hoses and joint faces for signs of staining or wetness, and rectify as necessary.
8 • It is important that antifreeze is used in the cooling system all year round, not just during the winter months. Don’t top up with water alone, as the antifreeze will become diluted.
Antifreeze type Long-life ethylene glycol based antifreeze*
* Refer to your BMW dealer for brand name and type recommendations
The coolant expansion tank incorporates a float device which indicates the level of coolant. When the upper end of the float protrudes no more than 20 mm above the filler neck, the level is correct. See the information on the expansion tank adjacent to the filler neck.
If topping-up is necessary, wait until the engine is cold. Slowly unscrew the expansion tank cap, to release any pressure present in the cooling system, and remove it.
Add a mixture of water and antifreeze to the expansion tank until the level of the coolant is just below the Kalt/Cold mark on the expansion tank, or until the top of the indicator float protrudes no more than 20 mm above the filler neck. Refit the cap and tighten it securely. Should you need to replace the coolant, click below
- Close + Open

Coolant replacement

Warning: Wait until the engine is cold before starting this procedure. Do not allow antifreeze to come in contact with your skin, or with the painted surfaces of the car. Rinse off spills immediately with plenty of water. Never leave antifreeze lying around in an open container, or in a puddle in the driveway or on the garage floor. Children and pets are attracted by its sweet smell, but antifreeze can be fatal if ingested.
1 With the engine completely cold, cover the expansion tank cap with a wad of rag, and slowly turn the cap anti-clockwise to relieve the pressure in the cooling system (a hissing sound may be heard). Wait until any pressure in the system is released, then continue to turn the cap until it can be removed.
2 Raise the front of the vehicle and support it securely on axle stands. Remove the engine undershield (see illustration) .
Engine undershield fasteners
3 Undo the fasteners and remove the undershield beneath the radiator.

N47 and N57 engines

4 Release the clamps, and disconnect the intercooler intake and outlet hoses (see illustration) . Examine the hose seals and renew if necessary.
Prise out the clip and disconnect the intercooler hoses
5 Unscrew the 2 retaining bolts and lower the intercooler from place (see illustration) .
Undo the bolt each side and lower the intercooler

All engines

6 On N47T engines, remove the engine undershield, and panel beneath the intercooler/radiator. No drain plug/tap is fitted to the radiator.
7 Bleed screws may be fitted to the EGR cooler, the coolant return hose and the coolant expansion tank (see illustrations) . Undo the screws (where applicable), remove the plastic cover from the top of the engine and open the bleed screws.
Coolant bleed screws may be located on the coolant expansion tank . . .
. . . the return hose . . .
. . . and the EGR cooler according to model
8 Position a suitable container beneath the drain plug(s) on the base of the radiator (where fitted). Unscrew the drain plug(s) and allow the coolant to drain into the container (see illustration) . On models without a radiator drain plug, release the clamp and disconnect the radiator lower hose.
Slacken the radiator drain plug
9 To fully drain the system, also unscrew the coolant drain plug from the right-hand side of the cylinder block and allow the remainder of the coolant to drain into the container (see illustration) . Access to the plug is extremely limited.
The cylinder block drain plug is located on the right-hand side
10 BMW insist that the cooling system is not filled with used coolant.
11 Once all the coolant has drained, fit a new sealing washer to the block drain plug and tighten it to 25 Nm (18 Ibf ft).

Cooling system flushing

12 If the antifreeze mixture has become diluted, then in time the cooling system may gradually lose efficiency, as the coolant passages become restricted due to rust, scale deposits, and other sediment. The cooling system efficiency can be restored by flushing the system clean.
13 The radiator should be flushed independently of the engine, to avoid unnecessary contamination.

Radiator flushing

14 To flush the radiator, disconnect the top and bottom hoses and any other relevant hoses from the radiator.
15 Insert a garden hose into the radiator top inlet. Direct a flow of clean water through the radiator, and continue flushing until clean water emerges from the radiator bottom outlet.
16 If after a reasonable period, the water still does not run clear, the radiator can be flushed with a good proprietary cooling system cleaning agent. It is important that their manufacturer’s instructions are followed carefully. If the contamination is particularly bad, insert the hose in the radiator bottom outlet, and reverse-flush the radiator.

Engine flushing

17 To flush the engine, remove the thermostat, then temporarily refit the thermostat cover. On models where the thermostat is integral with the housing, remove the housing to allow the water to flow out.
19 On completion of flushing, refit the thermostat and reconnect the hoses.
18 With the top and bottom hoses disconnected from the radiator, insert a garden hose into the radiator top hose. Direct a clean flow of water through the engine, and continue flushing until clean water emerges from the radiator bottom hose.

Cooling system filling

20 Where applicable, refit the intercooler, and the engine undershield.
21 Before attempting to fill the cooling system, make sure that all hoses and clips are in good condition, and that the clips are tight and the radiator and cylinder block drain plugs are securely tightened. Note that an antifreeze mixture must be used all year round, to prevent corrosion of the engine components (see following sub-Section).
Coolant quantity:
  4-cylinder engines:
    Manual transmission 7.5 litres
    Automatic transmission 7.9 litres
  6-cylinder engines:
    Manual transmision 7.8 litres
    Automatic transmission 8.2 litres
Antifreeze type Long-life ethylene glycol based antifreeze*
* Refer to your BMW dealer for brand name and type recommendations
22 Slacken the bleed screw(s).
23 Turn on the ignition, and set the heater control to maximum temperature, with the fan speed set to ‘low’. This opens the heating valves.
24 Remove the expansion tank filler cap. Fill the system by slowly pouring the coolant into the expansion tank to prevent airlocks from forming.
25 If the coolant is being renewed, begin by pouring in a couple of litres of water, followed by the correct quantity of antifreeze, then top-up with more water.
26 As soon as coolant free from air bubbles emerges from the bleed screw(s), tighten the screw(s) securely.
27 Once the level in the expansion tank starts to rise, squeeze the radiator top and bottom hoses to help expel any trapped air in the system. Once all the air is expelled, top-up the coolant level until the float in the expansion tank rises to indicate the maximum level, then refit the expansion tank cap (see illustration) .
The float indicates the coolant level. Refer to the markings on the top of the expansion tank
28 Start the engine and run it until it reaches normal operating temperature, then stop the engine and allow it to cool.
29 Check for leaks, particularly around disturbed components. Check the coolant level in the expansion tank, and top-up if necessary. Note that the system must be cold before an accurate level is indicated in the expansion tank. If the expansion tank cap is removed while the engine is still warm, cover the cap with a thick cloth, and unscrew the cap slowly to gradually relieve the system pressure (a hissing sound will normally be heard). Wait until any pressure remaining in the system is released, then continue to turn the cap until it can be removed.

Antifreeze mixture

30 Always use an ethylene-glycol based antifreeze which is suitable for use in mixed-metal cooling systems.
31 Before adding antifreeze, the cooling system should be completely drained, preferably flushed, and all hoses checked for condition and security.
32 After filling with antifreeze, a label should be attached to the expansion tank, stating the type and concentration of antifreeze used, and the date installed. Any subsequent topping-up should be made with the same type and concentration of antifreeze.
Caution: Do not use engine antifreeze in the windscreen/tailgate washer system, as it will damage the vehicle paintwork. A screenwash additive should be added to the washer system in the quantities stated on the bottle.
- Close + Open

Coolant replacement

Warning: Wait until the engine is cold before starting this procedure. Do not allow antifreeze to come in contact with your skin, or with the painted surfaces of the car. Rinse off spills immediately with plenty of water. Never leave antifreeze lying around in an open container, or in a puddle in the driveway or on the garage floor. Children and pets are attracted by its sweet smell, but antifreeze can be fatal if ingested.
1 With the engine completely cold, cover the expansion tank cap with a wad of rag, and slowly turn the cap anti-clockwise to relieve the pressure in the cooling system (a hissing sound may be heard). Wait until any pressure in the system is released, then continue to turn the cap until it can be removed.
2 Raise the front of the vehicle and support it securely on axle stands. Remove the engine undershield (see illustration) .
Engine undershield fasteners
3 Undo the fasteners and remove the undershield beneath the radiator.

N47 and N57 engines

4 Release the clamps, and disconnect the intercooler intake and outlet hoses (see illustration) . Examine the hose seals and renew if necessary.
Prise out the clip and disconnect the intercooler hoses
5 Unscrew the 2 retaining bolts and lower the intercooler from place (see illustration) .
Undo the bolt each side and lower the intercooler

All engines

6 On N47T engines, remove the engine undershield, and panel beneath the intercooler/radiator. No drain plug/tap is fitted to the radiator.
7 Bleed screws may be fitted to the EGR cooler, the coolant return hose and the coolant expansion tank (see illustrations) . Undo the screws (where applicable), remove the plastic cover from the top of the engine and open the bleed screws.
Coolant bleed screws may be located on the coolant expansion tank . . .
. . . the return hose . . .
. . . and the EGR cooler according to model
8 Position a suitable container beneath the drain plug(s) on the base of the radiator (where fitted). Unscrew the drain plug(s) and allow the coolant to drain into the container (see illustration) . On models without a radiator drain plug, release the clamp and disconnect the radiator lower hose.
Slacken the radiator drain plug
9 To fully drain the system, also unscrew the coolant drain plug from the right-hand side of the cylinder block and allow the remainder of the coolant to drain into the container (see illustration) . Access to the plug is extremely limited.
The cylinder block drain plug is located on the right-hand side
10 BMW insist that the cooling system is not filled with used coolant.
11 Once all the coolant has drained, fit a new sealing washer to the block drain plug and tighten it to 25 Nm (18 Ibf ft).

Cooling system flushing

12 If the antifreeze mixture has become diluted, then in time the cooling system may gradually lose efficiency, as the coolant passages become restricted due to rust, scale deposits, and other sediment. The cooling system efficiency can be restored by flushing the system clean.
13 The radiator should be flushed independently of the engine, to avoid unnecessary contamination.

Radiator flushing

14 To flush the radiator, disconnect the top and bottom hoses and any other relevant hoses from the radiator.
15 Insert a garden hose into the radiator top inlet. Direct a flow of clean water through the radiator, and continue flushing until clean water emerges from the radiator bottom outlet.
16 If after a reasonable period, the water still does not run clear, the radiator can be flushed with a good proprietary cooling system cleaning agent. It is important that their manufacturer’s instructions are followed carefully. If the contamination is particularly bad, insert the hose in the radiator bottom outlet, and reverse-flush the radiator.

Engine flushing

17 To flush the engine, remove the thermostat, then temporarily refit the thermostat cover. On models where the thermostat is integral with the housing, remove the housing to allow the water to flow out.
19 On completion of flushing, refit the thermostat and reconnect the hoses.
18 With the top and bottom hoses disconnected from the radiator, insert a garden hose into the radiator top hose. Direct a clean flow of water through the engine, and continue flushing until clean water emerges from the radiator bottom hose.

Cooling system filling

20 Where applicable, refit the intercooler, and the engine undershield.
21 Before attempting to fill the cooling system, make sure that all hoses and clips are in good condition, and that the clips are tight and the radiator and cylinder block drain plugs are securely tightened. Note that an antifreeze mixture must be used all year round, to prevent corrosion of the engine components (see following sub-Section).
Coolant quantity:
  4-cylinder engines:
    Manual transmission 7.5 litres
    Automatic transmission 7.9 litres
  6-cylinder engines:
    Manual transmision 7.8 litres
    Automatic transmission 8.2 litres
Antifreeze type Long-life ethylene glycol based antifreeze*
* Refer to your BMW dealer for brand name and type recommendations
22 Slacken the bleed screw(s).
23 Turn on the ignition, and set the heater control to maximum temperature, with the fan speed set to ‘low’. This opens the heating valves.
24 Remove the expansion tank filler cap. Fill the system by slowly pouring the coolant into the expansion tank to prevent airlocks from forming.
25 If the coolant is being renewed, begin by pouring in a couple of litres of water, followed by the correct quantity of antifreeze, then top-up with more water.
26 As soon as coolant free from air bubbles emerges from the bleed screw(s), tighten the screw(s) securely.
27 Once the level in the expansion tank starts to rise, squeeze the radiator top and bottom hoses to help expel any trapped air in the system. Once all the air is expelled, top-up the coolant level until the float in the expansion tank rises to indicate the maximum level, then refit the expansion tank cap (see illustration) .
The float indicates the coolant level. Refer to the markings on the top of the expansion tank
28 Start the engine and run it until it reaches normal operating temperature, then stop the engine and allow it to cool.
29 Check for leaks, particularly around disturbed components. Check the coolant level in the expansion tank, and top-up if necessary. Note that the system must be cold before an accurate level is indicated in the expansion tank. If the expansion tank cap is removed while the engine is still warm, cover the cap with a thick cloth, and unscrew the cap slowly to gradually relieve the system pressure (a hissing sound will normally be heard). Wait until any pressure remaining in the system is released, then continue to turn the cap until it can be removed.

Antifreeze mixture

30 Always use an ethylene-glycol based antifreeze which is suitable for use in mixed-metal cooling systems.
31 Before adding antifreeze, the cooling system should be completely drained, preferably flushed, and all hoses checked for condition and security.
32 After filling with antifreeze, a label should be attached to the expansion tank, stating the type and concentration of antifreeze used, and the date installed. Any subsequent topping-up should be made with the same type and concentration of antifreeze.
Caution: Do not use engine antifreeze in the windscreen/tailgate washer system, as it will damage the vehicle paintwork. A screenwash additive should be added to the washer system in the quantities stated on the bottle.

Brake and clutch fluid level

Warning: Brake fluid can harm your eyes and damage painted surfaces, so use extreme caution when handling and pouring it.
Warning: Do not use fluid that has been standing open for some time, as it absorbs moisture from the air, which can cause a dangerous loss of braking effectiveness.
HINT: The fluid level in the reservoir will drop slightly as the brake pads wear down, but the fluid level must never be allowed to drop below the MIN mark.

Before you start

9 • Make sure that the car is on level ground.

Safety first!

10 • If the reservoir requires repeated topping-up this is an indication of a fluid leak somewhere in the system, which should be investigated immediately.
11 • If a leak is suspected, the car should not be driven until the braking system has been checked. Never take any risks where brakes are concerned
Release the three clips and remove the lid from the driver’s side lower pollen filter housing.
The MAX and MIN marks are indicated on the side of the reservoir.
If topping-up is necessary, first wipe clean the area around the filler cap to prevent dirt entering the hydraulic system.
Unscrew the reservoir cap and carefully lift it out of position, taking care not to damage the level switch float.
Carefully add fluid, taking care not to spill it onto the surrounding components. Use only DOT 4 fluid; mixing different types can cause damage to the system. After topping-up to the correct level, securely refit the cap and wipe off any spilt fluid.

Power steering fluid level

12 • Park the car on level ground.
13 • Set the steering wheel straight-ahead.
14 • The engine should be turned off.
HINT: For the check to be accurate, the steering must not be turned once the engine has been stopped.

Safety first!

15 • The need for frequent topping-up indicates a leak, which should be investigated immediately.
The reservoir is located near the front of the engine compartment (see Underbonnet check points for exact location). Wipe clean the area around the reservoir filler neck and unscrew the filler cap/ dipstick from the reservoir.
Insert the dipstick into the reservoir (without screwing on the cap), then remove it. The fluid level should be between MIN and MAX. When topping-up, use the specified type of fluid and do not overfill the reservoir. When the level is correct, securely refit the cap.
Power steering fluid Dexron II* or Pentosin CHF11S (marked as ATF or CHF on the reservoir filler cap)
* Refer to your BMW dealer for brand name and type recommendations

Screenwasher fluid level*

16 * On models with a headlight washer system, the screenwasher is also used to clean the headlights.
17 • Screenwash additives not only keep the windscreen clean during foul weather, they also prevent the washer system freezing in cold weather – which is when you are likely to need it most. Don’t top-up using plain water as the screenwash will become too diluted, and will freeze during cold weather.
Caution: On no account use coolant antifreeze in the washer system – this could discolour or damage paintwork.
The screenwasher fluid reservoir is located at the right-hand side.
Unclip the cap. When topping-up, add a screenwash additive in the quantities recommended by the manufacturer. It could also be time to replace the wiper blades. For details, click below
- Close + Open

Wiper blade replacement

1 Check the condition of the wiper blades; if they are cracked or show any signs of deterioration, or if the glass swept area is smeared, renew them. Wiper blades should be renewed annually.
To remove a wiper blade, pull the arm away from the screen until it locks. Release the clip (arrowed) . . .
. . . and remove the plastic cover.
Rotate the blade 90° and disengage it from the arm.
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