Thermostat Kit – Fits Volvo Penta 4.3L, 5.0L, 5.7L, 8.1L Engines (Replaces 3831426)

Thermostat Kit – Fits Volvo Penta 4.3L, 5.0L, 5.7L, 8.1L Engines

This thermostat kit is designed for a wide range of Volvo Penta marine engines, including the 4.3L, 5.0L, 5.7L, and 8.1L V6/V8 models manufactured between 2001 and 2009. It covers various series such as Gi, GXi, OSi, OSXi, and designated V6/V8 models.

This kit serves as a direct replacement for Volvo Penta part number 3831426.

• Compatibility: Designed for gasoline/petrol engines.
• Installation: Direct replacement for a hassle-free installation.
• Key Feature: Includes a thermostat rated at 160°F (71°C) with an integrated rubber gasket for a leak-free seal.

Part Number Cross-Reference

Use this table to confirm equivalent part numbers.

Compatible Engine Models

Confirm your engine model/year in the table below.

Technical Specifications

Package Contents

• 1 × 160°F Thermostat with integrated rubber gasket (Replaces 3831426)

Installation Guide

1. Ensure the engine is completely cool before beginning. Disconnect the battery's negative terminal for safety.
2. Locate the thermostat housing on the engine. It is typically found where the main coolant hose connects to the engine block.
3. Place a drain pan under the housing to catch any spilled coolant. Loosen the hose clamp and detach the coolant hose.
4. Unscrew the bolts holding the thermostat housing in place and carefully lift it off, noting the orientation of the old thermostat.
5. Remove the old thermostat and gasket. Clean both mating surfaces on the engine and the housing to remove all debris.
6. Install the new thermostat in the same orientation as the old one. The new unit includes an integrated gasket for a secure seal.
7. Re-position the thermostat housing and tighten the bolts to the manufacturer's recommended torque specifications.
8. Reconnect the coolant hose and secure the clamp, then top off the coolant level in the system.
9. Reconnect the battery terminal. Start the engine and let it run, checking carefully for any leaks around the thermostat housing.
10. Monitor the engine temperature gauge to ensure it stays within the normal operating range.

Troubleshooting & FAQ

Q: How do I confirm this thermostat kit fits my engine?

A: This kit is designed for Volvo Penta 4.3L, 5.0L, 5.7L, and 8.1L Gi, GXi, OSi, OSXi, V6, and V8 series engines from 2001-2009. Please check the "Compatible Engine Models" table to verify that your specific model is listed. It is a direct replacement for OEM part number 3831426.

Q: What are the signs of a failing thermostat?

A: Common symptoms include engine overheating, the temperature gauge reading unusually low, or significant fluctuations in engine temperature. A stuck-open thermostat will prevent the engine from reaching operating temperature, while a stuck-closed one will cause overheating.

Q: What is the temperature rating of this thermostat?

A: This thermostat is rated to open at 160°F (71°C), which is the standard specification for the compatible Volvo Penta engines to ensure optimal performance and fuel efficiency.

Q: OEM vs. Aftermarket?

A: 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.

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

A: 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.

Q: What is your warranty and return policy?

A: 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.