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Porsche 928 (1978-1995) 928S4 5.0L 1987-92 Service Parts Belts All Types

Alternator belt. Porsche 964 (965) Turbo  ›  99919234550

Alternator belt. Porsche 964 (965) Turbo - 99919234550 - 1118006100
2
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99919234550/2
Product Information
Product Information

Alternator Belt

OE Match replacement alternator belt for Porsche 964 turbo models, manufactured in the correct 9.5 x 785mm size.

Fits:

  • Porsche 964 (911) TURBO 3.3L 1991-93
  • Porsche 964 (911) TURBO 3.6L 1991-93

Diagram Ref No 13A

The alternator belt is an important service component, transferring engine rotation to the alternator and helping maintain the vehicle's electrical charging system. A worn, cracked or incorrectly tensioned belt can slip or fail, resulting in reduced alternator performance and potentially leaving the vehicle without adequate battery charging.

What Does the Alternator Belt Do?

The alternator belt mechanically drives the alternator from the engine. As the engine runs, the belt transfers rotation to the alternator pulley, allowing the alternator to generate electricity and maintain battery charge.

Correct belt condition and tension are therefore essential for reliable operation of the charging system.

Why Do Alternator Belts Fail?

Drive belts are exposed to continuous movement, heat and changing engine speeds. The rubber material gradually deteriorates with age even on vehicles covering relatively low mileage.

Common causes of failure include:

Age-related rubber deterioration Cracking or splitting Incorrect belt tension Pulley misalignment Oil contamination Excessive heat Worn or damaged pulleys Long periods of vehicle storage

When Should It Be Replaced?

The alternator belt should be replaced if inspection reveals cracking, fraying, glazing, hardening or other deterioration.

Other warning signs can include:

Squealing or slipping noises Charging system problems Visible belt damage Difficulty maintaining correct belt tension Excessive belt movement

On classic Porsche models, periodic visual inspection is advisable regardless of mileage because deterioration can occur simply through age.

Checks During Replacement

When fitting a new alternator belt, also inspect:

Alternator pulley Crankshaft pulley Belt running surfaces Belt alignment Correct belt tension Associated mounting hardware Signs of oil contamination

Correct tension is important: an excessively loose belt can slip, while excessive tension can place unnecessary load on bearings and associated components.



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99919234550
99919234550

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Timing cam belt RD Tooth. Porsche 928 1983-96 - 92810515750 - CT584
2
Timing cam belt RD Tooth. Porsche 928 1983-96
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92810515750
Product Information
Product Information
Timing cam belt RD Tooth.
Cam belt 219 Round Tooth.



Fits:
Porsche 928 S2/S4/GT/GTS 1983-96

Click 'Zoom in' for large parts diagram.
Diagram Ref No 1.

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92810515750
92810515750

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Camshaft tensioner roller. Porsche 928 1983-95 - 92810551212, 04442
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Camshaft tensioner roller. Porsche 928 1983-95
Special Order item
92810551212
Product Information
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Camshaft tensioner roller.



Fits:
Porsche 928 S2 / S4 / GT / GTS 1983-95

Click 'Zoom in' for large parts diagram.
Diagram ref no 9.

Related reference numbers
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92810551212
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04442

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Camshaft idler roller. Porsche 928 1986-95 - 92810557104
4
Camshaft idler roller. Porsche 928 1986-95
92810557104/1
Product Information
Product Information
Camshaft Idler Roller.
The OE Match Camshaft Idler Roller  is a high-quality replacement timing belt guide roller designed to support and direct the camshaft timing belt within the engine timing system. As a critical component of the belt drive assembly, the idler roller helps maintain correct belt alignment, reduces vibration and ensures precise synchronisation between the crankshaft and camshaft.

Fits:
  • Porsche 928S4 5.0L 1987-92
  • Porsche 928GT 5.0L 1989-91
  • Porsche 928GTS 5.4L 1992-95
  
Diagram Ref No 10

Manufactured to OE specifications for fit, performance and durability, this camshaft idler roller is engineered to withstand continuous operation, high rotational speeds and demanding engine conditions. It is an essential service item during timing belt replacement and preventative maintenance, helping to preserve the reliability and accuracy of the engine timing system.  

What This Product Does:
  • Guides and supports the camshaft timing belt.
  • Maintains correct timing belt alignment and routing.
  • Helps reduce belt vibration and movement.
  • Promotes even belt wear and consistent operation.
  • Supports accurate synchronisation between crankshaft and camshaft.
  • Contributes to reliable engine timing and performance.

Symptoms Of Wear Or Failure:
  • Chirping, squealing or grinding noises from the timing belt area.
  • Excessive timing belt vibration.
  • Rough or noisy bearing operation.
  • Visible wear or damage to the roller surface.
  • Timing belt misalignment.
  • Uneven or accelerated timing belt wear.
  • Bearing looseness or excessive play.
  • Increased risk of timing belt failure.

Why Replacement Matters:

  • The camshaft idler roller operates continuously while the engine is running and is subjected to constant rotational forces, heat and bearing loads. Over time, bearing wear, loss of lubrication and material fatigue can reduce the roller's effectiveness and reliability.
  • A failing idler roller can negatively affect timing belt tracking and alignment, causing premature belt wear and placing additional stress on surrounding timing components. In severe cases, bearing seizure or roller failure may result in timing belt damage or loss of engine timing, potentially leading to costly engine repairs.



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

92810557104
92810557104

The product you are viewing cross references to these numbers