Alternator belt. Porsche 911 / 914

Alternator belt, Narrow V-belt.
Belt size: 10 x 713 mm
The V-belt runs between the crankshaft pulley and the alternator/fan pulley. It’s the primary mechanical link that spins the alternator to charge the battery and, on air-cooled 911s and 914-6 models, turns the engine cooling fan.

Fits:
Porsche 911 1965 - 1973
Porsche 911 Turbo 1976 >>
Porsche 911 SC 1974 - 1979 (Check Size of your Belt)
Porsche 911 SC 1980 - 1983
Porsche 911 3.2L 1984 - 1989
Porsche 914 1970 - 1976

Please note: Always confirm against the belt size currently fitted and pulley setup before ordering.

Why Replacement Matters - With age and mileage, belts:
• Crack, glaze, or harden, reducing grip
• Stretch, making correct tension impossible
• Begin to slip, causing charging issues and, on air-cooled engines, reduced cooling fan speed

A slipping or failing belt can lead to battery discharge, warning lights, overheating, or being stranded. Fitting a fresh belt restores reliable alternator and fan drive, protecting both the engine and electrical system.

When to Replace - Consider replacing the alternator belt if:
•  You see cracks, fraying, glazing, or missing chunks in the belt rubber
•  The belt squeals on startup or under load
•  The belt has stretched and can’t be tensioned correctly
•  You’re doing routine service on a classic 911 / 914-6 or preparing for a long trip
•  The car is undergoing engine-out work or restoration

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Related, superseded, cross reference or alternative numbers for comparison.

9991921765A

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