Thermostat Kit – Fits Volvo Penta 4.3-8.2L V6/V8 Engines (Replaces 3831426)

Thermostat Kit – Fits Volvo Penta 4.3-8.2L V6/V8 Engines (Replaces 3831426)

This thermostat kit is designed for a wide range of Volvo Penta gasoline marine engines from 1991 and newer, including 4.3L, 5.0L, 5.7L, 5.8L, 7.4L, 8.1L, and 8.2L models. It ensures reliable temperature control for optimal engine performance and cooling efficiency.

This kit is a direct replacement for Volvo Penta part numbers 3831426, 1544389, 3857962, 824200, 8757880, and Sierra 18-3539.

• Operating Temperature: Maintains a consistent 70°C (160°F) for freshwater cooled engines.
• Complete Kit: Includes the thermostat, O-ring, and gasket for a full replacement.
• Installation: Designed for direct replacement of the original thermostat assembly.

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 Thermostat (3831426)
• 1 x O-Ring
• 1 x Gasket

Installation Guide

1. Safety First: Ensure the engine is completely cool before starting. Disconnect the battery.
2. Drain Coolant: Place a drain pan under the engine block or heat exchanger and drain the coolant to a level below the thermostat housing.
3. Locate Housing: Find the thermostat housing, typically located where the top radiator hose meets the engine.
4. Remove Housing: Loosen and remove the bolts securing the housing cover. You may need to gently tap it to break the seal.
5. Remove Old Thermostat: Note the orientation of the old thermostat before lifting it out. Also, remove the old gasket or O-ring.
6. Clean Surfaces: Thoroughly clean the mating surfaces of the housing and engine block to remove any old gasket material or corrosion.
7. Install New Thermostat: Place the new thermostat into the housing in the correct orientation. Install the new gasket and O-ring as required by your model.
8. Reassemble: Re-install the housing cover and tighten the bolts to the manufacturer's recommended torque specification.
9. Refill Coolant: Refill the cooling system with the appropriate type and amount of coolant.
10. Check for Leaks: Reconnect the battery. Start the engine and let it warm up, carefully checking for any coolant leaks around the thermostat housing.
11. Final Check: Once the engine reaches operating temperature, check the temperature gauge to ensure it is stable within the normal range. Top off coolant if necessary.

Troubleshooting & FAQ

Q: How do I confirm this thermostat fits my specific engine?
A: Please review the "Compatible Engine Models" table on this page. Match your engine's model and year range to ensure compatibility. Comparing the part number to your engine's service manual is also a reliable method.

Q: What temperature is this thermostat rated for?
A: This is a 70°C (160°F) thermostat, intended for freshwater-cooled Volvo Penta gasoline engines. Using the correct temperature thermostat is critical for engine longevity and performance.

Q: What are common signs that my thermostat is failing?
A: A faulty thermostat can cause engine overheating, or the engine may run too cool and never reach proper operating temperature. You might notice erratic readings on your temperature gauge or see coolant leaking from the housing.

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.