How to remove and install an alternator on BMW Z4?

Removal begins with disconnecting the cable(s) from the negative battery terminal(s). Next, remove the air filter housing and the mass airflow (MAF) sensor. The engine cooling fan should be removed next. On automatic transmission models, remove the cooling fan and viscous coupling. The drivebelt should then be removed. Reach beneath the alternator and pull the air cooling hose down and off of the alternator rear cover. Proceed to remove the alternator cover rear mounting nuts and the rear cover. Remove the fasteners and disconnect the wiring from the rear of the alternator. To disconnect the alternator wiring, remove the rubber cover, unscrew the nut then unplug the connector. Remove the upper and lower alternator securing bolts. Finally, withdraw the alternator from the engine. For installation, it is a reversal of removal, bearing in mind the following points. When installing the tensioner idler pulley, ensure that the lug on the rear of the pulley assembly engages with the corresponding cut-out in the mounting bracket. Install all parts in the reverse order of removal.

Genuine BMW Z4 Alternator

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13 Alternators found

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BMW Z4 Alternator
Part Number: 12318634167
$1041.74 MSRP: $1551.03
You Save: $509.29 (33%)
Ships in 1-3 Business Days
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Product Specifications
- Replaces: 12-31-8-689-830, 12-31-8-654-280, 12-31-8-689-832, 12-31-8-689-831, 12-31-8-634-166
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2019-2025 BMW Z4 | 4 Cyl 2.0 L GAS, 6 Cyl 3.0 L GAS, M40i(G29), sDrive30i(G29)
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BMW Z4 Alternator
Part Number: 12317605478
$740.91 MSRP: $1088.38
You Save: $347.47 (32%)
Ships in 1-3 Business Days
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Product Specifications
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2012-2016 BMW Z4 | sDrive28i(E89)
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BMW Z4 Exchange Alternator
Part Number: 12317605479
$744.72 MSRP: $1190.94
You Save: $446.22 (38%)
Ships in 1-3 Business Days
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Product Specifications
- Other Name: Exchange Generator
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2012-2016 BMW Z4 | sDrive28i(E89)
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BMW Z4 Exchange Alternator
Part Number: 12317519620
$753.03 MSRP: $944.57
You Save: $191.54 (21%)
Ships in 1-3 Business Days
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Product Specifications
- Other Name: Exchange Compact Generator; Alternator
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2003-2005 BMW Z4 | 2.5i(E85), 3.0i(E85)
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BMW Z4 Alternator
Part Number: 12317558167
$771.18 MSRP: $1133.45
You Save: $362.27 (32%)
Ships in 1-3 Business Days
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Product Specifications
- Replaces: 12-31-7-558-218
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2009-2016 BMW Z4 | sDrive35i(E89), sDrive35is(E89)
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BMW Z4 EXCH. GENERATOR
Part Number: 12318689832
$1041.74 MSRP: $1551.03
You Save: $509.29 (33%)
Ships in 1-3 Business Days
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Product Specifications
- Replaced by: 12318634167
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2019-2020 BMW Z4 | M40i(G29), sDrive30i(G29)
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BMW Z4 Exchange Alternator
Part Number: 12317543083
$527.91 MSRP: $753.57
You Save: $225.66 (30%)
Ships in 1-3 Business Days
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Product Specifications
- Other Name: Exchange Generator; Alternator
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2006-2008 BMW Z4 | Coupe 3.0si(E86), Roadster 3.0i(E85), Roadster 3.0si(E85)
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BMW Z4 Rmfd Generator
Part Number: 12318689831
$1041.74 MSRP: $1551.03
You Save: $509.29 (33%)
Ships in 1-3 Business Days
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Product Specifications
- Replaced by: 12318634167
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2019-2020 BMW Z4 | M40i(G29), sDrive30i(G29)
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BMW Z4 EXCH. GENERATOR
Part Number: 12318689830
$1041.74 MSRP: $1551.03
You Save: $509.29 (33%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Replaced by: 12318634167
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2019-2020 BMW Z4 | M40i(G29), sDrive30i(G29)
View related parts
BMW Z4 Exchange Alternator
Part Number: 12317558218
$771.18 MSRP: $1133.45
You Save: $362.27 (32%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Other Name: Exchange Generator; Alternator
- Replaced by: 12317558167
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2009-2016 BMW Z4 | sDrive35i(E89), sDrive35is(E89)
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BMW Z4 Exchange Alternator
Part Number: 12317552816
$771.18 MSRP: $1133.45
You Save: $362.27 (32%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Other Name: Exchange Generator
- Replaced by: 12317552815
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2009-2011 BMW Z4 | sDrive30i(E89)
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BMW Z4 Alternator
Part Number: 12317552815
$771.18 MSRP: $1133.45
You Save: $362.27 (32%)
Ships in 1-3 Business Days
ADD TO CART
Product Specifications
- Other Name: Rp Alternator
- Replaces: 12-31-7-552-816
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2009-2011 BMW Z4 | sDrive30i(E89)
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BMW Z4 Alternator
Part Number: 12317605061
Product Specifications
- Warranty: This genuine part is guaranteed by BMW's factory warranty.
Fits the following Vehicles:
- 2012-2016 BMW Z4 | sDrive28i(E89)

BMW Z4 Alternator

BMW Z4 Alternator supplies a steady electricity to keep the sports car's battery charged and its lights, infotainment, and engine controls fueled. Inside a compact aluminum shell, a belt on the front of the engine rotates a pulley on a shaft, rotating the rotor inside stationary stator windings. This motion produces alternating current that diodes in the Alternator convert to direct current that can be applied right away and can also be applied to top up the battery. To prevent dim lights or blown fuses, a voltage regulator, which though it was once a separate unit is now typically monitored by the powertrain computer, causes the field current to be fine-tuned so that output is not too high or too low. Early BMW Z4 roadsters shared the same brushed, air-cooled Alternator design as the rest of the BMW, but later model years adopted revised regulators integrated with engine management for faster response while maintaining the same fan-cooled, two-bearing layout that are all familiar with. Regardless of generation, the Alternator is mounted in front of the inline-six or four-cylinder engines and uses a serpentine belt instead of gears, making it a simple task to replace and increasing Alternator service life. The primary difference between versions lies in the sophistication of the electronics control rather than the basic level of mechanical construction because it keeps the Z4's electronics stable and allows each and every BMW Z4 to have consistent voltage and spirited performance.

If you are looking for OEM BMW Z4 Alternator, we highly recommend to shop with us. Not only do we offer budget friendly prices, but we also provide fast delivery. In addition, we have a hassle-free return policy on all genuine BMW Z4 Alternator that come backed by the manufacturer's warranty.

BMW Z4 Alternator Parts Questions & Experts Answers

Exchange Alternator
12317519620
Q:
How to remove and install an alternator on BMW Z4?
Posted by Jared J.
A:
Removal begins with disconnecting the cable(s) from the negative battery terminal(s). Next, remove the air filter housing and the mass airflow (MAF) sensor. The engine cooling fan should be removed next. On automatic transmission models, remove the cooling fan and viscous coupling. The drivebelt should then be removed. Reach beneath the alternator and pull the air cooling hose down and off of the alternator rear cover. Proceed to remove the alternator cover rear mounting nuts and the rear cover. Remove the fasteners and disconnect the wiring from the rear of the alternator. To disconnect the alternator wiring, remove the rubber cover, unscrew the nut then unplug the connector. Remove the upper and lower alternator securing bolts. Finally, withdraw the alternator from the engine. For installation, it is a reversal of removal, bearing in mind the following points. When installing the tensioner idler pulley, ensure that the lug on the rear of the pulley assembly engages with the corresponding cut-out in the mounting bracket. Install all parts in the reverse order of removal.
Answered by BMW Parts Specialist Javier / Apr 17, 2023