Thermostat Kit – Fits Volvo Penta 4.3-8.2L V6/V8 Engines (Replaces Volvo Penta 3831426)
Thermostat Kit – Fits Volvo Penta 4.3-8.2L V6/V8 Engines (Replaces Volvo Penta 3831426) is backordered and will ship as soon as it is back in stock.
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Delivery and Shipping
Delivery and Shipping
Orders are typically processed within 1–2 business days.
U.S. orders usually arrive within 6–15 days, depending on stock location and destination.
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Thermostat Kit – Fits Volvo Penta 4.3-8.2L V6/V8 Engines (Replaces Volvo Penta 3831426) is backordered and will ship as soon as it is back in stock.
Product Details
This Thermostat Kit – Fits Volvo Penta 4.3-8.2L V6/V8 Engines (Replaces 3831426) is designed for a wide range of Volvo Penta gasoline marine engines, including 4.3L, 5.0L, 5.7L, 5.8L, 7.4L, 8.1L, and 8.2L models from 1991 and up. It ensures reliable temperature control for optimal engine performance and cooling efficiency.
It serves as a direct replacement for Volvo Penta part numbers 3831426, 1544389, 3857962, 824200, 8757880, and Sierra 18-3539.
- Engineered as a direct-fit replacement for straightforward installation.
- Features the latest design for improved performance and reliability.
- Kit includes thermostat, O-ring, and gasket for a complete service.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Volvo Penta | 3831426 |
| Volvo Penta | 1544389 |
| Volvo Penta | 3857962 |
| Volvo Penta | 824200 |
| Volvo Penta | 8757880 |
| Sierra | 18-3539 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
Designed for the following Volvo Penta engine models.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| Volvo Penta | 4.3GXi, 4.3GXi-B, 4.3GXi-BF | 4.3L | 4-Stroke | 1991-up | 3831426 | Freshwater cooled engines (70°C) |
| Volvo Penta | 5.0GXi-A | 5.0L | 4-Stroke | 1991-up | 3831426 | |
| Volvo Penta | 5.7Gi-A, 5.7GXi-A, 5.7GXi-B | 5.7L | 4-Stroke | 1991-up | 3831426 | |
| Volvo Penta | 5.7GiI-A, 5.7GXiI-A, 5.7GXiI-B | 5.7L | 4-Stroke | 1991-up | 3831426 | |
| Volvo Penta | 5.7GSiI-A | 5.7L | 4-Stroke | 1991-up | 3831426 | |
| Volvo Penta | 5.8L (All Models) | 5.8L | 4-Stroke | 1991-up | 3831426 | |
| Volvo Penta | 7.4L (All Models) | 7.4L | 4-Stroke | 1991-up | 3831426 | |
| Volvo Penta | 8.1L (All Models) | 8.1L | 4-Stroke | 1991-up | 3831426 | |
| Volvo Penta | 8.2L (All Models) | 8.2L | 4-Stroke | 1991-up | 3831426 | |
| Volvo Penta | MD40A | Diesel | 4-Stroke | 3831426 | ||
| Volvo Penta | TMD40A, TMD40B, TMD40C | Diesel | 4-Stroke | 3831426 | ||
| Volvo Penta | AQD40A | Diesel | 4-Stroke | 3831426 | ||
| Volvo Penta | TAMD40A, TAMD40B | Diesel | 4-Stroke | 3831426 | ||
| Volvo Penta | AD40B | Diesel | 4-Stroke | 3831426 | ||
| Volvo Penta | AQAD40A, AQAD40B | Diesel | 4-Stroke | 3831426 |
Technical Specs
- Product Type
- Thermostat Kit with Gaskets
- Installation
- Direct replacement
- Temperature Rating
- 70°C (158°F) / 160°F
- Fuel Type
- Gasoline
- Connection
- Direct fit
- Fitting Type
- Direct fit with included gaskets
- Operating Temperature
- 70°C (158°F)
- Other Technical Attributes
- Latest version design for improved reliability
What’s in the Box
- 1 x Thermostat (3831426)
- 1 x O-Ring
- 1 x Gasket
Installation Notes
- Ensure the engine is completely cool and disconnect the battery.
- Drain the engine coolant to a level below the thermostat housing.
- Carefully remove the fasteners securing the thermostat housing cover.
- Remove the cover and note the orientation of the old thermostat before taking it out.
- Remove the old gasket or O-ring and thoroughly clean all mating surfaces of any residue.
- Install the new thermostat in the correct orientation as noted earlier.
- Place the new gasket and/or O-ring into position on the housing.
- Re-install the housing cover and tighten fasteners to the manufacturer's recommended torque specification.
- Refill the cooling system with the appropriate coolant.
- Reconnect the battery, start the engine, and carefully check for any leaks as it warms up.
Troubleshooting & FAQ
How do I know if my thermostat is failing?
Common signs of a faulty thermostat include engine overheating, the engine temperature gauge reading unusually low (stuck open), erratic temperature fluctuations, and observed coolant leaks from the thermostat housing area.
What is the correct operating temperature for this thermostat?
This thermostat is rated for 70°C (158°F), often referenced as a 160°F thermostat. This is a common temperature for many freshwater cooled marine engines.
Is this thermostat for raw water or freshwater cooled systems?
This 70°C model is primarily specified for freshwater (closed cooling) systems. Raw water (open cooling) systems typically use a lower temperature thermostat. Always confirm your specific engine's cooling system requirements before installation.
Do I need to use sealant with the included gaskets?
The included O-ring and gasket are designed to create a seal without additional chemical sealants. However, always refer to your engine's official service manual for procedures specific to your model, as some applications may have unique requirements.
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.
Shipping speed & cost
We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
Warranty & returns
Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.
Safety & Important Info
- Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
- This is an aftermarket replacement, not an OEM component.
- Professional installation is recommended for safety and performance.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
- Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
- Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.
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