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Porsche 911 & 912 (1965-1989) Engine Electrical Alternator / Generator

Alternator Pulley / Pulley Nuts

Alternator Pulley / Pulley Nuts

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DISPLAYING 17 to 27 (of 27 products)
1 2
Generator pulley hub. Porsche 356 / 912 - 54709304
3
Generator pulley hub. Porsche 356 / 912
54709311/1
Product Information
Product Information

Generator Pulley Hub

The OE Match Generator Pulley Hub is a replacement component designed for the generator pulley assembly fitted to classic Porsche 356 and 912 engines.

Fits:

  • Porsche 911 1965-1968 912 SWB (F)
  • Porsche 356 1950-55
  • Porsche 356A 1955-59
  • Porsche 356B 1959-63
  • Porsche 356C 1963-65

Diagram ref no 11

The hub supports correct pulley mounting and alignment, helping maintain reliable belt-driven operation of the generator and engine cooling fan.

What Does It Do?

The generator pulley hub provides the mounting connection between the generator shaft and pulley assembly, helping maintain correct positioning and drive-belt alignment.

Why Does It Fail?

Common causes include:

  • Wear around the mounting surfaces
  • Corrosion and age-related deterioration
  • Damage from incorrect installation
  • Excessive vibration or pulley misalignment
  • Wear caused by loose fastening components

When Should It Be Replaced?

Replace if the hub shows excessive wear, cracking, deformation or damage that prevents secure pulley mounting.

Inspect the hub whenever the generator pulley is removed or when investigating pulley wobble and abnormal belt wear.

Checks & Installation

Inspect the generator shaft, pulley halves and associated fastening hardware for damage.

Ensure the hub is correctly seated and the pulley runs true. Adjust belt tension according to the relevant Porsche workshop instructions.

Key Features

  • OE Match replacement generator pulley hub
  • Designed for classic Porsche generator assemblies
  • Supports correct pulley positioning
  • Helps maintain drive-belt alignment
  • Suitable for engine servicing and restoration

Porsche 356 & 912 Generator Pulley Parts

The generator pulley assembly is essential to the belt-driven charging and cooling systems of classic Porsche 356 and 912 engines.

Replacing a worn generator pulley hub helps maintain correct pulley alignment and dependable operation of the generator and cooling fan.



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Related, superseded, cross reference or alternative numbers for comparison.

54709311
54709304

The product you are viewing cross references to these numbers
Inner Generator Pulley I Half. Porsche 356 / 912 - 53909315
3
Inner Generator Pulley I Half. Porsche 356 / 912
53909315
Product Information
Product Information
Inner Generator Pulley I Half. 
Maintain correct alternator and cooling fan belt operation with this OE Match Inner Generator Pulley Half, manufactured as a direct replacement. Produced to OE-style specifications, this pulley half forms part of the generator pulley assembly, providing the correct belt alignment and tension when used with the matching outer pulley half and shims.

Fits:
  • Porsche 911 1965-1968 2.0L / 912 SWB (F)
  • Porsche 356 1950-55
  • Porsche 356A 1955-59
  • Porsche 356B 1959-63
  • Porsche 356C 1963-65  

Diagram Ref No 7

Over time, the original pulley half can become worn, scored, distorted, or corroded through continual belt contact, heat, and engine vibration. Damage or wear can prevent the drive belt from seating correctly, resulting in belt slip, excessive wear, charging issues, or reduced cooling fan performance. Replacing a worn pulley half restores proper belt alignment and reliable operation of the generator and cooling fan drive. This OE Match component is ideal for routine maintenance, engine repairs, and Porsche restoration projects.  

What This Product Does:
  • Forms part of the generator pulley assembly.
  • Supports correct drive belt alignment.
  • Helps maintain accurate belt tension when used with the appropriate shims.
  • Drives the generator and engine cooling fan.
  • Reduces the risk of belt slip and premature belt wear.
  • Replaces worn or damaged original pulley halves.
  • Provides an OE-style fit and dependable quality.

Symptoms Of Wear Or Failure:
  • Scored or worn pulley grooves.
  • Corrosion or pitting on the pulley surface.
  • Bent or distorted pulley half.
  • Drive belt slipping or squealing.
  • Uneven or accelerated belt wear.
  • Difficulty maintaining correct belt tension.
  • Visible damage affecting pulley alignment.

Why Replacement Matters:

  • The inner generator pulley half is a critical component of the generator and cooling fan drive system, ensuring the drive belt runs true and maintains the correct tension. A worn or damaged pulley half can cause belt misalignment, slipping, increased belt wear, reduced charging efficiency, and compromised engine cooling.
  • Replacing the inner generator pulley half restores proper belt alignment and dependable operation of the generator and cooling fan, helping to protect the charging and engine cooling systems from unnecessary wear. Manufactured as a direct replacement and produced to OE-style specifications, this OE Match component provides the correct fit, dependable quality, and long-lasting durability, making it an excellent choice for Porsche maintenance, engine repairs, and restoration projects.



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

53909315
53909315

The product you are viewing cross references to these numbers
Inner generator pulley nut. Porsche 356 / 912 - 54709303
2
Inner generator pulley nut. Porsche 356 / 912
Special Order item
54709303
Product Information
Product Information
Inner generator pulley nut (for 53909315 / 53909316).

Fits:
Porsche 356 1950-65
Porsche 912 1965-69

Diagram ref no 11

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

54709303
54709303

The product you are viewing cross references to these numbers
Inner generator pulley nut. Porsche 356 / 912 - 54709303
3
Inner generator pulley nut. Porsche 356 / 912
54709303/1
Product Information
Product Information

Inner Generator Pulley Nut

The OE Match Inner Generator Pulley Nut is a replacement fastening component for the generator pulley assembly fitted to classic Porsche 356 and 912 models.

Fits:

  • Porsche 911 1965-1968 912 SWB (F)
  • Porsche 356 1950-55
  • Porsche 356A 1955-59
  • Porsche 356B 1959-63
  • Porsche 356C 1963-65

Diagram ref no 11

Designed to replace a worn, damaged or missing original component, it helps maintain secure assembly of the generator pulley and supports reliable operation of the engine's belt-driven accessories.

Check the original pulley assembly and part number before ordering.

What Does It Do?

The inner generator pulley nut forms part of the pulley fastening arrangement, helping secure the components that transmit drive from the crankshaft to the generator and cooling fan.

Why Does It Fail?

Common causes include:

  • Damaged or stripped threads
  • Corrosion and age-related deterioration
  • Incorrect tightening during servicing
  • Wear from repeated removal
  • Damage caused by incorrect tools

When Should It Be Replaced?

Replace if the nut has damaged threads, corrosion or visible deformation, or if it cannot be secured correctly.

Inspect the fastening components whenever the generator pulley or drive belt is removed.

Checks & Installation

Check the condition of the pulley, shaft threads and associated fastening components before fitting.

Ensure correct pulley alignment and belt tension, following the appropriate Porsche workshop instructions.

Key Features

  • OE Match replacement fastening component
  • Porsche part reference 54709303
  • Designed for classic generator pulley assemblies
  • Replaces damaged or missing original hardware
  • Suitable for engine servicing and restoration

Porsche 356 & 912 Generator Pulley Parts

The generator pulley assembly is an important part of the belt-driven charging and cooling system fitted to classic Porsche engines.

Maintaining the correct pulley fasteners helps ensure secure operation and prevents problems caused by damaged or incorrectly fitted components.



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

54709303
54709303

The product you are viewing cross references to these numbers
Outer Generator Pulley II Half. Porsche 356 / 912 - 53909316
2
Outer Generator Pulley II Half. Porsche 356 / 912
53909316
Product Information
Product Information
Outer Generator Pulley II Half.
Maintain reliable generator and cooling fan performance with this OE Match Outer Generator Pulley Half, manufactured as a direct replacement. Produced to OE-style specifications, this outer pulley half works together with the inner pulley half and adjustment shims to provide the correct drive belt alignment and tension, ensuring efficient operation of the generator and engine cooling fan.

Fits:
  • Porsche 911 1965-1968 2.0L / 912 SWB (F)
  • Porsche 356 1950-55
  • Porsche 356A 1955-59
  • Porsche 356B 1959-63
  • Porsche 356C 1963-65  

Diagram Ref No 8

Over time, the original pulley half can become worn, scored, distorted, or corroded through continuous belt contact, heat cycles, and engine vibration. A damaged pulley can prevent the belt from running correctly, leading to belt slip, excessive belt wear, reduced charging performance, or compromised engine cooling. Replacing a worn outer pulley half restores correct belt positioning and dependable operation of the drive system. This OE Match component is ideal for routine maintenance, engine repairs, and Porsche restoration projects.  

What This Product Does:
  • Forms part of the generator pulley assembly.
  • Works with the inner pulley half to secure the drive belt.
  • Helps maintain correct drive belt alignment and tension.
  • Drives the generator and engine cooling fan.
  • Reduces the risk of belt slip and premature belt wear.
  • Replaces worn or damaged original pulley halves.
  • Provides an OE-style fit and dependable quality.

Symptoms Of Wear Or Failure:
  • Scored or worn pulley contact surfaces.
  • Bent or distorted pulley half.
  • Corrosion or pitting on the pulley.
  • Drive belt squealing or slipping.
  • Excessive or uneven belt wear.
  • Difficulty achieving correct belt tension.
  • Visible pulley damage affecting belt alignment.

Why Replacement Matters:

  • The outer generator pulley half is an essential component of the generator and cooling fan drive assembly, ensuring the drive belt is correctly positioned and tensioned for efficient operation. A worn or damaged pulley can cause belt misalignment, slipping, accelerated belt wear, reduced charging efficiency, and diminished cooling fan performance.
  • Replacing the outer generator pulley half restores proper belt alignment and reliable operation of both the generator and engine cooling fan, helping to protect the charging and cooling systems from unnecessary wear. Manufactured as a direct replacement and produced to OE-style specifications, this OE Match component provides the correct fit, dependable quality, and long-lasting durability, making it an excellent choice for Porsche maintenance, engine repairs, and restoration projects.



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

53909316
53909316

The product you are viewing cross references to these numbers
Tensioning cap for Bosch alternator. Porsche 911 - 90160342702
2
Tensioning cap for Bosch alternator. Porsche 911
Special Order item
90160342703
Product Information
Product Information
Tensioning cap for Bosch alternator. White galvanised.

Fits:
Porsche 911 1965-68
*** Only up to engine number 0909000

Diagram ref no 12

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

90160342703
90160342702

The product you are viewing cross references to these numbers
Tensioning cap for Bosch alternator. Porsche 911 / 914 - 90160342702
2
Tensioning cap for Bosch alternator. Porsche 911 / 914
Special Order item
90160342702
Product Information
Product Information
Tensioning cap for Bosch alternator.

Fits:
Porsche 911 1965-73
Porsche 914 1970-76

Diagram ref no 12

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

90160342702
90160342702

The product you are viewing cross references to these numbers
Tensioning cap for Bosch alternator. Porsche 911 / 914 - 90160342702 - URO-012725
3
Tensioning cap for Bosch alternator. Porsche 911 / 914
90160342702/1
Product Information
Product Information
Tensioning cap for cars with Bosch Alternator with M14 centre shaft.

Fits:
Porsche 911 1965-1973
Porsche 914 1970-1973

Diagram ref no 12

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

90160342702
90160342702

The product you are viewing cross references to these numbers
Tensioning cap for Motorola alternator. Porsche 911 / 912 / 914 - 90160342800, 90160342801, 90160342803, 1690150100
2
Tensioning cap for Motorola alternator. Porsche 911 / 912 / 914
Special Order item
90160342803
Product Information
Product Information
Tensioning cap for Motorola alternator.

Fits:
Porsche 911 1965-81
Porsche 912 1965-70
Porsche 914-6 1969-73

Diagram ref no 11

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

90160342803
90160342800
90160342801
90160342803
1690150100

The product you are viewing cross references to these numbers
Tensioning cap for Motorola alternator. Porsche 911 / 912 / 914 / 930 Turbo - 90160342800, 90160342801, 90160342803 - URO-012726, 1690150100
2
Tensioning cap for Motorola alternator. Porsche 911 / 912 / 914 / 930 Turbo
90160342803/1
Product Information
Product Information

OE Match tensioning cap for selected Porsche 911, 912 and 914 Motorola alternator applications. Supplied diagram information also identifies use on specified 911 Turbo assemblies.

Fits

  • Porsche 911 1965-81
  • Porsche 912 1965-70
  • Porsche 914-6 1969-73

Check fitment for your specific vehicle (model, year, engine) before ordering.

Diagram ref no: 11


What This Product Does

This is the tensioning cap used within the specified alternator or generator pulley assembly. It is a separate mechanical component, rather than a complete alternator, voltage regulator or belt.

Technical Details

  • Part reference: 90160342803.
  • Brand: OE Match.
  • Motorola generator identification appears in the supplied 911 1965–69, 911 1970–73 and 914-6 diagrams.
  • CAL exclusions apply to the specified 1974–77 and Turbo 1975–77 diagram applications.

Symptoms of Fault

Loose pulley hardware, belt squeal, vibration or visible pulley wobble warrant inspection of the pulley assembly. These symptoms do not establish that the tensioning cap itself is faulty; belt condition, alignment and adjoining components also need checking.

Why Replacement Matters

Renewing damaged or worn pulley hardware can form part of an alternator repair or classic Porsche restoration. Match the cap to the installed generator and inspect the surrounding assembly rather than selecting it by vehicle model alone.

FAQs

  • Will this fit every alternator on the listed vehicles?
    No universal compatibility is stated. Confirm the generator identification, part reference and applicable diagram notes.
  • Does a charging fault mean this cap needs replacing?
    No. Charging problems require diagnosis; inspect the belt drive, battery, wiring and earth connections before choosing replacement parts.
  • What should be checked during pulley work?
    Inspect belt condition, pulley alignment, retaining hardware and alternator bearing condition.


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

90160342803
90160342800
90160342801
90160342803

The product you are viewing cross references to these numbers
Tensioning cap for Motorola alternator. Porsche 911 65-68 - 90160342802
2
Tensioning cap for Motorola alternator. Porsche 911 65-68
Special Order item
90160342802
Product Information
Product Information
Tensioning cap for Motorola alternator. White galvanised.

Fits:
Porsche 911 F (1965 - 1968)
* Only with Motorola three-phase generator and up to engine number 0909000

Diagram ref no 11

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

90160342802
90160342802

The product you are viewing cross references to these numbers
DISPLAYING 17 to 27 (of 27 products)
1 2
Also found on these pages
About Alternator Pulley / Pulley Nuts

Alternator Pulleys & Pulley Nuts – Reliable Power Delivery for Porsche Performance

Alternator pulleys and pulley nuts are essential components in your Porsche’s drive system. These parts ensure the alternator operates smoothly by transferring power from the engine’s drive belt to the alternator shaft, keeping your electrical and charging systems functioning at peak efficiency. A properly functioning pulley system helps maintain battery charge, power accessories, and prevent belt slippage — vital for both performance and reliability.

At Design911, we offer a complete range of genuine and high-quality alternator pulleys and pulley nuts for Porsche models including 911, Boxster, Cayman, Cayenne, Macan, Panamera and transaxle cars. Each component is precision-engineered for strength, balance, and durability, ensuring consistent rotational efficiency and long service life under demanding driving conditions.

What Do Alternator Pulleys and Pulley Nuts Do?

Alternator pulleys and their corresponding nuts work together to drive the alternator via the serpentine or fan belt. Their primary functions include:

  • Transferring engine power from the drive belt to the alternator shaft.
  • Regulating belt tension and preventing slippage at high RPMs.
  • Absorbing vibration to ensure smooth alternator operation.
  • Maintaining consistent battery charging and electrical performance.

A correctly fitted pulley and nut assembly ensures stable electrical output and prolongs the lifespan of both the alternator and belt system.

Why Do Alternator Pulleys and Nuts Fail?

Although engineered for longevity, pulleys and nuts experience constant mechanical stress and heat, leading to wear or failure over time. Common causes include:

  • Bearing wear or internal corrosion within the pulley.
  • Excessive vibration loosening or damaging the pulley nut.
  • Belt misalignment or over-tensioning accelerating pulley wear.
  • Contamination from dirt or oil affecting rotation balance.
  • Metal fatigue or rust from long-term exposure and age.

Symptoms of pulley or nut failure include belt squeal, uneven alternator speed, battery warning lights, or visible pulley wobble when the engine is running.

Why Replace Faulty Alternator Pulleys and Nuts?

A damaged or unbalanced pulley can cause belt failure, charging issues, and alternator damage. Replacing worn components ensures proper alignment, smooth operation, and optimal charging performance.

Benefits of replacement include:

  • Restored alternator performance and charging efficiency.
  • Prevention of belt slippage or premature wear.
  • Reduced vibration and noise from the drive system.
  • Improved reliability and component longevity.

All pulleys and nuts offered by Design911 are built to meet or exceed exacting engineering standards, using high-grade metals and precision machining to ensure perfect balance, strength, and durability.

FAQ: Porsche Alternator Pulleys & Pulley Nuts

1. What are the signs of a failing alternator pulley on a Porsche?
Common signs of a bad alternator pulley include squealing or chirping noises, belt slippage, visible pulley wobble, or the battery warning light illuminating on the dashboard. You may also notice power fluctuations or reduced charging performance if the pulley or nut is worn or loose.

2. Can I replace a Porsche alternator pulley myself?
While some experienced mechanics and enthusiasts may be able to replace an alternator pulley at home, it often requires specialised tools such as a pulley removal socket or impact wrench. For precise alignment and correct torque settings, it’s recommended to have the replacement done by a qualified technician or Porsche specialist.

3. What causes an alternator pulley or pulley nut to fail?
Alternator pulleys and nuts can fail due to metal fatigue, misalignment, over-tensioned belts, or bearing wear. Exposure to oil or debris, as well as age-related corrosion, can also cause pulleys to seize or wobble. Replacing them promptly prevents further damage to your alternator and drive belt.

4. How often should alternator pulleys and nuts be replaced on a Porsche?
There is no fixed interval, but most Porsche alternator pulleys last between 60,000 and 100,000 miles, depending on driving conditions. Regular inspections during belt or alternator servicing are essential. If you hear noise, experience charging issues, or see visible pulley wear, replacement is recommended.

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