Alternator Drive Belt – Fits Volvo Penta 4.3GL, 4.3GS & OMC Marine Engines (Replaces 3852504)

Alternator Drive Belt – Fits Volvo Penta 4.3GL, 4.3GS & OMC Marine Engines (Replaces 3852504)

This high-quality aftermarket alternator drive belt is engineered for reliable power transmission in a wide range of Volvo Penta and OMC marine engines. It is specifically designed to fit Volvo Penta 4.3L (262ci) V6 models from 1985–1993 and various OMC Sterndrive engines from 2.3L to 8.2L manufactured between 1982 and 1993.

This v-belt serves as a direct replacement for Volvo Penta part number 3852504 and OMC part numbers 0778031, 0910371, and 3852504. Manufactured from durable neoprene/rubber with polyester/aramid reinforcement, it meets or exceeds OEM specifications for performance and longevity.

• Engineered with a V-belt design for optimal pulley grip and performance.
• Constructed to withstand harsh marine environments with an operating temperature range of -40°C to 100°C.

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.

Volvo Penta

OMC

Technical Specifications

Package Contents

• 1 x Alternator Drive Belt (3852504)

Installation Guide

1. Safety First: Disconnect the boat's battery before beginning work.
2. Locate Belt: Identify the alternator and the existing drive belt routing around the crankshaft and alternator pulleys.
3. Release Tension: Loosen the alternator's adjusting and mounting bolts to create slack in the belt.
4. Remove Old Belt: Carefully slip the old, worn belt off the pulleys.
5. Install New Belt: Route the new belt according to your engine's specific diagram, ensuring it is properly seated in all pulley grooves.
6. Set Tension: Pry the alternator outward to apply tension to the new belt and tighten the adjusting bolt. Proper tension is typically around 1/2 inch of deflection when pushed firmly.
7. Secure Alternator: Once tension is correct, fully tighten all alternator mounting bolts.
8. Final Check: Reconnect the battery, start the engine, and listen for any unusual noises. Ensure the belt is tracking correctly on the pulleys.

Troubleshooting & FAQ

How do I confirm this belt fits my Volvo Penta or OMC engine?
This belt is designed for Volvo Penta 4.3GL, 4.3GS, and 4.3GI V6 engines (1985-1993) and various OMC Sterndrive models from 2.3L to 8.2L (1982-1993). Always cross-reference your engine model and year with our compatibility tables above. The surest method is to match your original part number to one of the replacements: Volvo Penta 3852504 or OMC 0778031, 0910371, 3852504.

What are common signs that my alternator belt needs replacing?
Look for visible signs of wear such as cracking, fraying, glazing (shiny surface), or missing chunks. Audible symptoms include a persistent high-pitched squeal from the engine, especially on startup or when electrical load increases. Dimming lights or a battery/charging warning light on your dashboard also indicate the alternator may not be spinning effectively due to a slipping belt.

How often should I inspect or replace my alternator belt?
It is good practice to visually inspect engine belts at the start of each season and during regular maintenance. While there's no fixed replacement interval, belts should be replaced immediately if they show signs of significant wear or damage, or typically every 3-5 years as a preventative measure depending on usage and conditions.

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.