V-Belt – Fits Volvo Penta AQ120-AQ170, 230A-251A Marine Engines (Replaces 831524, 834548, 958313, 966694)

V-Belt – Fits Volvo Penta AQ120-AQ170 & 230A-251A Marine Engines

This V-belt is designed for a wide range of Volvo Penta 4-cylinder gasoline inboard and sterndrive engines, including models from the AQ120 through AQ170 series and the 230A through 251A series, typically manufactured between the 1970s and 1990s.

It serves as a direct replacement for multiple OEM and aftermarket part numbers, ensuring a precise fit for your engine's alternator system. Please cross-reference your part number with the table below to confirm compatibility.

• Application: Alternator/Generator Belt for 35-amp systems.
• Material: Durable synthetic rubber with high-strength reinforcement cords.
• Installation Method: External engine accessory belt.

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Compatible Engine Models

Confirm your engine model/year in the table below.

Technical Specifications

Package Contents

• 1 x V-Belt for Alternator (Replaces 831524, 834548, 958313, 966694)

Installation Guide

1. Disconnect the boat's battery to prevent electrical hazards.
2. Locate the alternator and identify the tensioner pulley or adjustment bolt.
3. Loosen the alternator's mounting and adjustment bolts to release tension on the old belt.
4. Carefully remove the old, worn V-belt from the pulleys.
5. Inspect all pulleys for wear, damage, or misalignment before proceeding.
6. Route the new V-belt around the crankshaft, water pump, and alternator pulleys, ensuring it is properly seated in the grooves.
7. Apply tension to the belt by adjusting the alternator's position. Proper tension is typically a 1/2 inch (13mm) of deflection under moderate thumb pressure.
8. Securely tighten the alternator's adjustment and mounting bolts.
9. Reconnect the battery, then start the engine briefly to check for proper belt tracking and listen for any unusual noises.

Troubleshooting & FAQ

How can I be sure this V-belt fits my specific Volvo Penta engine?

Verify your engine model is listed in the 'Compatible Engine Models' table. Crucially, check that your engine uses one of the OEM part numbers this belt replaces: 831524, 834548, 958313, or 966694. This belt is specifically for systems with a 35-amp alternator.

What are the common signs that my alternator V-belt needs replacement?

Common signs include visible cracking, glazing, or fraying on the belt's surface. You may also hear a high-pitched squealing noise during engine operation, especially at startup or when under load, or notice your battery is not charging correctly.

How often should I replace my engine's V-belt?

There is no fixed replacement interval for all engines, but a routine inspection during annual service is recommended. Replace the belt proactively if it shows any signs of wear or damage, or as specified in your engine's service manual.

The length is 1075 mm. Is this the only dimension I need to worry about?

Length is the most critical dimension for fitment and proper tension. While width and profile are also important, this belt is manufactured to match the specific profile required for the listed Volvo Penta applications and replacement part numbers.

OEM vs. Aftermarket?

This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

How fast do you ship and how much does it cost?

We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

What is your warranty and return policy?

This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.