049-903-137-C VW Alternator Belt - Type 2 Bus, 411, 412, Diesel Golf & Jetta

VW Alternator & Fan Belt – 049-903-137-C

Ensure your battery stays charged and your cooling system functions perfectly with this high-quality V-Belt. This specific belt size is engineered to handle the high rotational speeds and heat of both classic air-cooled Type 4 engines and the high-compression 1.6L Diesel engines found in early water-cooled Volkswagens. A worn or slipping belt can lead to dimming lights, a dead battery, or engine overheating, making it a critical maintenance item for any vintage VW.

The 049-903-137-C features a notched (cogged) design that allows the belt to run cooler and wrap more efficiently around small-diameter pulleys. Manufactured from EPDM rubber with high-tensile internal cords, it resists stretching and glazing even under heavy loads. This belt is also the standard choice for Type 3 owners who have performed the popular "Smallternator" conversion, upgrading from the original generator to a modern high-output alternator.

Detailed Vehicle Compatibility This belt fits the following models and engine configurations:

VW 411:

• 1971, 1972

VW 412:

• 1973, 1974

VW Transporter (Type 2 / Bus):

• 1972, 1973, 1974, 1975, 1976, 1977, 1978, 1979

VW Golf (Diesel):

• 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992

VW Jetta (Diesel):

• 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992

Product Highlights & Features Cogged Design: The notched underside increases flexibility and surface area, providing better grip on the pulley and reducing the risk of "belt squeal."

Heat Resistant: Constructed from specialized rubber compounds that withstand the high engine bay temperatures of air-cooled Type 4 and Diesel engines.

Conversion Ready: The perfect fit for VW Type 3 motors (1962-1973) that have been converted to an alternator setup using a "Smallternator" kit.

Exact OE Specs: Built to the 10mm x 965mm factory dimensions for a precise fit that doesn't require over-extending your alternator adjustment bracket.

Technical Specifications Part Number: 049-903-137-C

Dimensions: 10mm Width x 965mm Length

Type: V-Belt (Cogged/Notched)

Material: EPDM Rubber with Polyester Cords

Installation & Maintenance Tips Check Tension Regularly: A new belt will "stretch" slightly during its first few hours of operation. Check the tension after the first 50 miles; you should have about 1/2" of play at the longest span between pulleys.

Pulley Alignment: If your belts are wearing prematurely or "flipping," check the alignment of your alternator pulley. On conversion engines, shim washers may be needed to ensure the belt runs perfectly straight.

Carry a Spare: Because this belt is essential for both charging and (on air-cooled models) engine cooling, it is highly recommended to keep a spare 049-903-137-C in your vehicle's emergency tool kit.

Avoid Over-Tightening: Over-tightening a belt can put excessive side-load on your alternator and water pump bearings, leading to premature component failure.