Alternator Genuine Porsche part 911603155AU

Alternator 12V 75A – Internal Regulator

Restore dependable charging performance with this OEM Supplier 12V 75A Alternator, equipped with an internal voltage regulator. Manufactured by an Original Equipment supplier, this alternator is produced to the same demanding standards as the component originally fitted by Porsche, providing the quality, reliability and fitment expected from factory-specification electrical components.

Fits:

• Porsche 911 1978-1983 3.0L / SC
• Porsche 911 1975-1977 3.0L Turbo (930)
• Porsche 911 1978-1983 3.3L Turbo (930) 

The alternator is one of the most important components of the vehicle's electrical system. While the engine is running, it generates electricity to power essential systems including the ignition, lighting, fuel injection, instruments, heating and ventilation controls, whilst simultaneously recharging the battery. A failing alternator can quickly lead to a discharged battery, poor engine performance and complete electrical failure.

This unit is manufactured for precise fitment and dependable long-term operation, making it an ideal replacement for worn or failed original alternators during routine maintenance or restoration.

What Does the Alternator Do?

The alternator converts mechanical energy from the engine into electrical energy.

Its primary functions include:

• Charging the vehicle battery.
• Supplying electrical power whilst the engine is running.
• Maintaining a stable charging voltage.
• Supporting ignition and fuel systems.
• Powering lighting and electrical accessories.
• Preventing battery discharge during normal driving.

The internal voltage regulator continuously controls the alternator output, ensuring the battery and electrical components receive the correct charging voltage without overcharging.

Why Replace the Alternator?

Alternators are subjected to constant heat, vibration and high rotational speeds throughout their service life.

Common causes of failure include:

• Worn bearings.
• Failed internal voltage regulator.
• Worn brushes.
• Damaged slip rings.
• Internal winding faults.
• Diode pack failure.
• Corrosion.
• Age-related wear.

Replacing a worn alternator restores reliable charging performance and helps prevent unexpected breakdowns.

Symptoms of a Failing Alternator

Common signs include:

• Battery warning light illuminated.
• Battery repeatedly going flat.
• Slow engine cranking.
• Dim or flickering headlights.
• Unstable voltage.
• Electrical accessories operating poorly.
• Intermittent charging.
• Bearing noise from the alternator.
• Burning electrical smell in severe cases.

Ignoring these symptoms can eventually leave the vehicle unable to start once the battery becomes fully discharged.

Important Installation Information

This alternator is suitable for Porsche 911 models (1978-1983) using an internal voltage regulator.

For Porsche 911 turbo 3.0ltr (1975-1977) applications, the following additional components are required:

• Resistor 91164198100 × 1
  
• Air Deflector 91110603305 × 1
  
• Cable Connector 111971511 × 2       

Voltage: 12V
Power: 75 Amp.
Direction of rotation: Clockwise (CW)
Attachment: 6 bolts, Radius 135 mm
Controller: internal
Pulley: no

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

91160312004

The product you are viewing cross references to these numbers

12 Volt 90 Amp Alternator 

The Porsche Alternator is a high-quality 12 Volt 90 Amp charging system component designed for Porsche 911 and Porsche 911 turbo models. As one of the most important electrical components on the vehicle, the alternator generates electrical power while the engine is running and continuously recharges the battery to maintain reliable operation of the vehicle's electrical systems.

Fits:

• Porsche 911 1984-1986 3.2L
• Porsche 911 1987-1989 3.2L G50
• Porsche 911 1978-1989 3.3L Turbo (930)

From powering the ignition system and fuel delivery components to supporting lighting, instrumentation, heating and other electrical accessories, the alternator plays a crucial role in the day-to-day reliability and performance of your Porsche. Without a properly functioning alternator, the battery will gradually discharge, leading to starting difficulties, electrical faults and eventually complete vehicle shutdown.

Overall length: 173mm
Voltage: 12V
Power: 90Amp
Direction of rotation: clockwise (CW)
Fixing: 6 studs
Controller: internal
Pulley: not supplied

Whether you're maintaining an air-cooled Porsche 911, servicing a Porsche 911 turbo or carrying out a restoration project, replacing a worn alternator helps ensure dependable performance and protects the vehicle's electrical system.

What Does an Alternator Do?

The alternator converts mechanical energy generated by the engine into electrical energy. Driven by the engine belt system, it supplies power to the vehicle while simultaneously charging the battery.

The alternator is responsible for:

Recharging the battery while driving Powering electrical systems and accessories Maintaining stable system voltage Supporting ignition and fuel system operation Ensuring reliable starting performance

A healthy alternator is essential for keeping every electrical system operating correctly.

Symptoms of Alternator Wear or Failure

Alternators operate continuously whenever the engine is running and are subjected to heat, vibration and electrical load. Over time, internal components such as bearings, brushes, voltage regulators and diodes can wear or fail.

Common symptoms of alternator failure include:

Battery warning light illuminated Repeated flat batteries Slow or difficult engine starting Flickering headlights Dimming dashboard lights Electrical accessories operating intermittently Low charging voltage Unusual whining or grinding noises Burning electrical smell Vehicle stalling due to insufficient voltage

In many cases, alternator failure develops gradually before progressing to complete charging system failure.

Why Alternator Replacement Matters

A faulty alternator can leave the battery unable to recharge properly, eventually causing loss of electrical power and unexpected breakdowns.

Replacing a worn alternator helps:

Restore correct battery charging Improve electrical system reliability Prevent roadside breakdowns Maintain stable voltage output Extend battery life Protect sensitive electrical components Eliminate charging system warning lights Improve overall vehicle dependability

For classic and performance Porsche models, maintaining a healthy charging system is essential for reliable operation and long-term ownership enjoyment.

Features & Benefits

• 12 Volt, 90 Amp output
• Provides reliable battery charging
• Maintains stable electrical system voltage
• Supports ignition and fuel system operation
• Durable construction for long service life
• Ideal for maintenance, repairs and restoration projects       

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

91160312005

The product you are viewing cross references to these numbers

Fits:
Porsche 911 1984-89 3.2L
Porsche 930 1978-89 3.3L

Voltage: 12 V
Alternator Charge Current: 90 A
Plug Type ID: B+, B-, D+
Number of ribs: 0
Pulleys: without belt pulley
Plug Type: Ring Connector

Please note:
Reconditioned Alternators are sold on an exchange basis, A surcharge of £200.00 will be held and then refunded when the old one is returned.

PLEASE NOTE:

• The surcharge for this reconditioned part will be refunded when the exchange unit is received and approved by us and the relevant manufacturer.
• Please note, surcharge refunds often take an average of 6 to 8 weeks to be approved by the manufacturer.
• Acceptance of the exchange part is at the manufacturer's discretion, based on the part being fit for reconditioning.
• All surcharges and exchanges are subject to our terms and conditions.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

91160312005

The product you are viewing cross references to these numbers

Alternator nut protecting cap

Fits:
Porsche 911 1984-89

Diagram ref no 13

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Related, superseded, cross reference or alternative numbers for comparison.

91160312701

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Alternator.
Keep your Porsche's charging system operating reliably with this OE Match Alternator, manufactured as a direct replacement. Produced to OE-style specifications, this alternator is designed to generate electrical power while the engine is running, supplying electricity to the vehicle's electrical systems and maintaining the battery at the correct state of charge.

Fits:

• Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
• Porsche 911 1978-1983 3.0L / SC  

The alternator is a vital component that powers everything from the ignition and lighting system to fuel delivery, instrumentation, and charging functions. Over time, internal bearings, brushes, voltage regulation components, or windings can wear through continuous operation, heat, and age, leading to reduced charging performance or complete failure. Replacing a worn alternator restores dependable electrical output and helps ensure reliable starting and operation. This OE Match component is ideal for routine maintenance, electrical system repairs, and Porsche restoration projects.  

What This Product Does:

• Generates electrical power while the engine is running.
• Charges the vehicle's battery during operation.
• Supplies power to the ignition and electrical systems.
• Maintains consistent charging voltage.
• Supports reliable engine starting and vehicle operation.
• Replaces worn or failing original alternators.
• Provides an OE-style fit and dependable quality.

Symptoms Of Wear Or Failure:

• Battery warning light illuminated.
• Battery repeatedly losing charge.
• Dim or flickering headlights.
• Electrical accessories operating intermittently.
• Whining, grinding, or bearing noise from the alternator.
• Difficulty starting due to low battery charge.
• Low or inconsistent charging voltage.
• Visible damage or excessive wear to the alternator.

Why Replacement Matters:

• The alternator is responsible for supplying electrical power to the vehicle while simultaneously recharging the battery. A failing alternator can lead to poor charging performance, battery drain, unreliable starting, and the eventual loss of essential electrical systems, potentially leaving the vehicle unable to operate.
• Replacing the alternator restores the correct charging capacity, ensuring dependable electrical performance and protecting the battery from unnecessary strain. Manufactured as a direct replacement and produced to OE-style specifications, this OE Match alternator provides the correct fit, dependable quality, and long-lasting durability, making it an excellent choice for Porsche maintenance, electrical system repairs, and restoration projects.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

91160312002

The product you are viewing cross references to these numbers

Alternator 14V, Alternator charge current: 115A
new unit.



Fits:
Porsche 964 1989-94
Porsche 993 1994-98

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96460315601

The product you are viewing cross references to these numbers

Alternator 12V-55A.
Replace: 91160310600, 90160311400, 90160311300.



This is a NEW part not an exchange part, so no old part is required. This alternator is usable for all old "small" type alternator stand.

Fits
Porsche 911 65-77 with internal regulator.

For Installation Instructions please CLICK HERE

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901603106DX

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Alternator 14V 60A.

Fits:
Porsche 911 1965-74

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91160312000

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Alternator 12V 75A – Internal Regulator

Keep your Porsche's charging system operating reliably with this OE Match 12V 75A Alternator, equipped with an internal voltage regulator. Manufactured to OE specifications, this replacement alternator provides dependable charging performance, helping maintain battery health and ensuring all electrical systems receive a stable power supply.

Fits:
Porsche 911 1978-1983 3.0L / SC
Porsche 911 1975-1977 3.0L Turbo (930)
Porsche 911 1978-1983 3.3L Turbo (930)

The alternator is one of the most important components of the vehicle's electrical system. While the engine is running, it generates electricity to power essential systems including the ignition, lighting, fuel injection, instruments, heating and ventilation controls, whilst simultaneously recharging the battery. A failing alternator can quickly lead to a discharged battery, poor engine performance and complete electrical failure.

This OE Match unit is manufactured for precise fitment and dependable long-term operation, making it an ideal replacement for worn or failed original alternators during routine maintenance or restoration.

What Does the Alternator Do?

The alternator converts mechanical energy from the engine into electrical energy.

Its primary functions include:

• Charging the vehicle battery.
• Supplying electrical power whilst the engine is running.
• Maintaining a stable charging voltage.
• Supporting ignition and fuel systems.
• Powering lighting and electrical accessories.
• Preventing battery discharge during normal driving.

The internal voltage regulator continuously controls the alternator output, ensuring the battery and electrical components receive the correct charging voltage without overcharging.

Why Replace the Alternator?

Alternators are subjected to constant heat, vibration and high rotational speeds throughout their service life.

Common causes of failure include:

• Worn bearings.
• Failed internal voltage regulator.
• Worn brushes.
• Damaged slip rings.
• Internal winding faults.
• Diode pack failure.
• Corrosion.
• Age-related wear.

Replacing a worn alternator restores reliable charging performance and helps prevent unexpected breakdowns.

Symptoms of a Failing Alternator

Common signs include:

• Battery warning light illuminated.
• Battery repeatedly going flat.
• Slow engine cranking.
• Dim or flickering headlights.
• Unstable voltage.
• Electrical accessories operating poorly.
• Intermittent charging.
• Bearing noise from the alternator.
• Burning electrical smell in severe cases.

Ignoring these symptoms can eventually leave the vehicle unable to start once the battery becomes fully discharged.

Important Installation Information

This alternator is suitable for Porsche 911 models (1978-1983) using an internal voltage regulator.

For Porsche 911 turbo 3.0ltr (1975-1977) applications, the following additional components are required:

• Resistor 91164198100 × 1
  
• Air Deflector 91110603305 × 1
  
• Cable Connector 111971511 × 2       

Voltage: 12V
Power: 75 Amp.
Direction of rotation: Clockwise (CW)
Attachment: 6 bolts, Radius 135 mm
Controller: internal
Pulley: no

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

91160312004

The product you are viewing cross references to these numbers