Volvo Penta MD30A / MD40A Marine Diesel Engine Thermostat – 170°F (77°C), Replaces 3831425
Volvo Penta MD30A / MD40A Marine Diesel Engine Thermostat – 170°F (77°C), Replaces 3831425 is backordered and will ship as soon as it is back in stock.
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Volvo Penta MD30A / MD40A Marine Diesel Engine Thermostat – 170°F (...
Volvo Penta MD30A / MD40A Marine Diesel Engine Thermostat – 170°F (77°C), Replaces 3831425 is backordered and will ship as soon as it is back in stock.
Product Details
This aftermarket marine engine thermostat is designed for specified Volvo Penta diesel engines in the MD series. It is a single thermostat with a nominal opening temperature of 170°F (77°C), helping the engine maintain its intended operating temperature in the fresh-water cooling circuit.
The thermostat is intended for Volvo Penta MD30A and MD40A applications. The MD30A requires two thermostats; the MD40A requires one thermostat. Confirm the engine model and the existing part reference before ordering.
- Single replacement thermostat.
- Nominal opening temperature: 170°F (77°C).
- For specified Volvo Penta MD30A and MD40A marine diesel engines.
- Aftermarket replacement for the listed manufacturer and aftermarket reference numbers.
Part Number Matrix
Use these reference numbers to compare the thermostat with the part being replaced. Reference numbers do not replace confirmation of the exact engine application.
| Reference Type | Part Number |
|---|---|
| Volvo Penta reference | 1544097 |
| Volvo Penta reference | 1544297 |
| Volvo Penta reference | 3831425 |
| Volvo Penta reference | 467014 |
| Volvo Penta reference | 875787 |
| Volvo Penta reference | 875789 |
| Sierra aftermarket reference | 18-3660 |
Engine Compatibility
Fitment is limited to the applications identified below. Year, serial-number and engine-configuration details were not provided, so verify the model and reference number against the engine service information before installation.
| Brand | Engine Model | Fuel | Opening Temperature | Quantity Required |
|---|---|---|---|---|
| Volvo Penta | MD30A | Diesel | 170°F (77°C) | 2 thermostats |
| Volvo Penta | MD40A | Diesel | 170°F (77°C) | 1 thermostat |
Technical Specifications
- Product Type
- Marine engine thermostat
- Cooling System Application
- Fresh-water cooling circuit
- Engine Type
- Volvo Penta marine diesel engine
- Opening Temperature
- 170°F (77°C)
- Product Quantity
- 1 thermostat
- Installation
- Replacement installation in the original thermostat housing
What's in the Box
- 1 x Thermostat
Gaskets, seals and other installation hardware are not confirmed as included. Reuse or replacement of these items should be determined from the engine service procedure and the condition of the original parts.
Installation Notes
- Allow the engine and coolant to cool completely before beginning work.
- Disconnect the battery and drain the coolant as required by the engine service procedure.
- Remove the thermostat housing and note the orientation of the existing thermostat.
- Remove the old thermostat and clean the mating surfaces without damaging the housing or engine components.
- Install the replacement thermostat in the same orientation as the original part.
- Inspect the gasket or seal and replace it if required by the service procedure or if it is damaged. A gasket or seal is not confirmed as included with this product.
- Reinstall the housing and tighten the fasteners to the engine manufacturer's specified torque.
- Refill and bleed the cooling system using the correct coolant and procedure for the engine.
- Start the engine, allow it to warm up, and check the thermostat housing and cooling system for leaks.
Troubleshooting & FAQ
How do I know if the thermostat may be failing?
Possible symptoms include overheating, an engine that runs below its normal temperature, slow warm-up, or unstable temperature readings. These symptoms can also be caused by coolant, pump, sensor or circulation problems, so diagnose the complete cooling system.
What temperature is this thermostat rated for?
The listed opening temperature is 170°F (77°C). This is the thermostat opening specification and is not a guarantee that every engine operating condition will remain at exactly that temperature.
How many thermostats do I need?
The specified MD30A application requires two thermostats, while the specified MD40A application requires one. This listing contains one thermostat.
Does this product include a gasket?
A gasket or seal is not confirmed as included. Check the engine service procedure and replace sealing components as required for a leak-free installation.
Is this an OEM thermostat?
This listing is for an aftermarket replacement thermostat. The manufacturer and aftermarket reference numbers shown in the part-number matrix are provided for identification and compatibility checking.
Is this thermostat suitable for another Volvo Penta model?
Do not assume fitment for models not listed on this page. Confirm the exact engine model and the reference number in the engine service documentation before ordering.
Safety & Important Information
- Work only on a completely cool engine and cooling system.
- Use appropriate personal protective equipment when handling coolant and engine components.
- Dispose of drained coolant in accordance with local regulations.
- Verify the engine model, cooling-system configuration and reference number before purchase.
- Professional installation is recommended when the correct procedure or torque specifications are uncertain.
About This Replacement Part
This replacement thermostat is supplied for the specified Volvo Penta marine diesel applications and is intended to restore temperature control when the original thermostat is worn, stuck or no longer operating correctly.
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