Bosch 12V Generator (New) | VW Type 1 1967–1973 & Type 2 1967–1968 | No Core Required (98-9031-B)

Bosch 12-Volt Generator (New) | VW Type 1 & Type 2 (1967–1973)

Restore the reliability of your air-cooled charging system with a brand-new Bosch 12-Volt Generator. This is a 100% new unit, not a remanufactured core, ensuring maximum longevity and consistent output for your classic VW. Designed as a direct replacement for the transition-era Type 1 and Type 2 models, it provides the factory-correct fitment and period-correct look that enthusiasts demand.

Because this is a new unit, there is no core charge or return required, saving you the hassle and expense of shipping your old part back.

Vehicle Fitment

• VW Type 1 (Beetle): 1967–1973 (12V)
• VW Type 2 (Bus): 1967–1968 (12V)

Why Choose Bosch?

Built to original equipment specifications for a perfect fit and reliable performance, this genuine Bosch unit is 100% new construction — no used components, featuring all-new bearings, brushes, and windings.

Key Features & Benefits

• Genuine Bosch Quality: Built to original equipment specifications for a perfect fit and reliable performance.
• 100% New Construction: No used components; features all-new bearings, brushes, and windings.
• Direct Fit: Specifically designed for 12V Type 1 (1967–1973) and Type 2 (1967–1968) engines.
• Hassle-Free: No core required—keep your original or save on return shipping.

Technical Specifications

• Type: 12-Volt DC Generator, brand-new (not remanufactured)
• Construction: All-new bearings, brushes, and windings
• Core Charge: None required
• Manufacturer: Bosch
• Part Number: 98-9031-B
• SKU: #E40

Installation

Replacing a generator is a straightforward task, but precision is key to ensuring your belt alignment and tension are correct. Safety First: Always disconnect the battery before beginning any electrical work.

1. Preparation & Removal

1. Disconnect the Battery: Remove the negative terminal to prevent accidental shorts.
2. Remove the Belt: Loosen the nut on the generator pulley. Remove the outer half of the pulley and the fan belt. Keep track of your adjustment shims.
3. Disconnect Wiring: Mark and remove the wires from the terminals (typically D+ and DF). Note the ground wire location if applicable.
4. Remove Components: * Remove the generator strap bolt and pull the strap back.
   • Remove the four bolts securing the fan shroud backing plate to the generator.
   • Carefully pull the generator toward the passenger side (or rear) to slide it out of the fan shroud.

2. Transferring the Fan

• You will need to transfer your original cooling fan and hub to the new unit.
• Important: Inspect the fan for cracks or chips. An unbalanced fan can vibrate and destroy the bearings on your brand-new Bosch unit.
• Torque the fan nut to approximately 40 ft-lbs. Ensure the fan spins freely without hitting the backing plate.

3. Installation

1. Seat the Generator: Slide the generator and fan assembly back into the fan shroud. Ensure the cooling fan is properly centered in the shroud opening.
2. Secure Backing Plate: Reinstall the four screws on the fan shroud backing plate.
3. Tighten the Strap: Position the generator so the terminals are upright and tighten the mounting strap.
4. Wiring: Reconnect the wires to the correct terminals (D+ and DF). Ensure the connections are clean and tight.
5. Set Belt Tension: Reinstall the pulley and belt. Use the shims between the pulley halves to achieve approximately 1/2" (13mm) of deflection in the belt.

   Tip: Extra shims belong on the outside of the pulley, under the nut.

4. Technical Step: Polarizing the Generator

Since this is a brand-new DC generator, it may need to be polarized to ensure it charges in the correct direction.

1. Reconnect the battery.
2. With the engine OFF, use a small jumper wire to momentarily (for about 1 second) connect the B+ (Battery) terminal on the regulator to the D+ terminal on the generator.
3. You should see a small spark; the generator is now polarized.

5. Testing

Start the engine and verify that the "Gen" or "Alt" light on the dashboard turns off. Use a multimeter at the battery; you should see a reading of approximately 13.8 to 14.2 volts while the engine is running at high idle.

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