Belt Tensioner – Fits Volvo Penta 4.3L, 5.0L, 5.7L, 8.1L Marine Engines (Replaces 3885250, 3587858)

Belt Tensioner – Fits Volvo Penta 4.3L, 5.0L, 5.7L, & 8.1L Marine Engines

This aftermarket serpentine belt tensioner is engineered for a precise fit on a wide range of Volvo Penta marine engines. It maintains the correct tension on the engine's serpentine belt, ensuring that accessories like the alternator, water pump, and power steering pump operate efficiently and reliably.

Designed as a direct replacement, this component matches OEM specifications for straightforward installation and dependable performance. It is compatible with Volvo Penta 4.3L, 5.0L, 5.7L, and 8.1L GL, Gi, GXi, and OSi models, as well as V6 and V8 series engines.

• Installation: Direct replacement for a hassle-free fit.
• Construction: Built with a durable metal housing to withstand the harsh marine environment.
• Compatibility: Replaces multiple Volvo Penta and PCM/Crusader part numbers.

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 Belt Tensioner (3885250)

Explosion Diagram

Installation Guide

1. Safety First: Ensure the engine is off and cool, then disconnect the battery's negative terminal.
2. Locate Tensioner: Identify the serpentine belt tensioner on the front of the engine.
3. Release Tension: Use a wrench or serpentine belt tool on the tensioner's designated bolt or square slot to rotate it against spring pressure, loosening the belt.
4. Remove Belt: While holding the tensioner, carefully slip the serpentine belt off the tensioner pulley.
5. Remove Old Tensioner: Unbolt and remove the old tensioner assembly from the engine block. Note the position of any locating dowels.
6. Install New Tensioner: Position the new tensioner, ensuring it is properly seated, and install the mounting bolts.
7. Torque Bolts: Tighten the mounting bolts to the manufacturer's recommended torque specifications.
8. Reinstall Belt: Route the serpentine belt around all pulleys according to the engine's belt diagram.
9. Apply Tension: Rotate the new tensioner again to create enough slack to slide the belt fully onto the last pulley. Slowly release the tensioner to tighten the belt.
10. Final Check: Reconnect the battery. Start the engine and listen for any unusual noises, and visually confirm the belt is tracking correctly on all pulleys.

Troubleshooting & FAQ

How do I know if my belt tensioner is failing?
Common signs include a persistent squealing, chirping, or rattling noise from the engine bay, especially on startup or during acceleration. You might also notice premature or uneven wear on the serpentine belt, or flickering lights and other issues with belt-driven accessories.

Will this fit my specific Volvo Penta 5.7GXi-H engine?
Yes, this tensioner is designed as a direct replacement for a wide range of Volvo Penta models, including the 5.7GXi-H. To ensure a perfect match, always cross-reference your engine model and original part number with the information provided in our compatibility tables.

Is a special tool required for installation?
For most installations, a standard socket set and a breaker bar or a dedicated serpentine belt tool are sufficient. The tool provides the necessary leverage to safely release the spring tension while you remove and reinstall the belt.

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.