50°C (122°F) Outboard Thermostat – Fits Suzuki DF40/DF50/DF60/DF70 and DT9.9–DT65; Replaces 17670-93962 and 5030742
50°C (122°F) Outboard Thermostat – Fits Suzuki DF40/DF50/DF60/DF70 and DT9.9–DT65; Replaces 17670-93962 and 5030742 is backordered and will ship as soon as it is back in stock.
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50°C (122°F) Outboard Thermostat – Fits Suzuki DF40/DF50/DF60/DF70 ...
50°C (122°F) Outboard Thermostat – Fits Suzuki DF40/DF50/DF60/DF70 and DT9.9–DT65; Replaces 17670-93962 and 5030742 is backordered and will ship as soon as it is back in stock.
Product Details
This aftermarket 50°C (122°F) outboard thermostat is a single replacement thermostat for selected Suzuki outboard engines and compatible OMC, Johnson, and Evinrude applications. It is intended to regulate cooling-system operation at the specified 50°C (122°F) opening temperature.
The supplier lists this thermostat as a replacement or cross-reference for Suzuki part numbers 17670-93960, 17670-93961, 17670-93962, 17670-93963, 17670-93964 and for OMC, Johnson, or Evinrude numbers 5030742, 5031175, and 0769469. Aftermarket reference 18-S939 is also listed. Always compare the original thermostat and confirm the complete engine model, year or model code, and stroke before ordering.
- 50°C (122°F) opening temperature.
- Replacement thermostat for selected Suzuki, OMC, Johnson, and Evinrude outboards.
- Sold as one thermostat; gasket or O-ring is not included unless specifically stated by the seller.
- Aftermarket replacement, not an OEM-branded component.
Part Number Matrix
These are supplier-listed replacement and cross-reference numbers. A part-number match should be confirmed against the engine model and application before installation.
| Brand or Reference | Part Number |
|---|---|
| Suzuki | 17670-93960 |
| Suzuki | 17670-93961 |
| Suzuki | 17670-93962 |
| Suzuki | 17670-93963 |
| Suzuki | 17670-93964 |
| OMC / Johnson / Evinrude | 5030742 |
| OMC / Johnson / Evinrude | 5031175 |
| OMC / Johnson / Evinrude | 0769469 |
| Aftermarket reference | 18-S939 |
Engine Compatibility
The company fitment information lists selected Suzuki DF and DT applications from 25 to 70 HP, plus OMC, Johnson, and Evinrude J/BJ applications from 70 to 140 HP. Keep the model, year or model code, horsepower, and stroke together when checking compatibility.
| Brand | Model or Application | Rated HP | Stroke | Year or Model Code |
|---|---|---|---|---|
| Suzuki | DF40 | 40 | 4-Stroke | Confirm exact year and model code |
| Suzuki | DF50X-K10 | 50 | 4-Stroke | 1999–2010 as listed |
| Suzuki | DF60 | 60 | 4-Stroke | Confirm exact year and model code |
| Suzuki | DF70W-K9 | 70 | 4-Stroke | 1998–2009 as listed |
| Suzuki | DT9.9K / DT9.9K | 9.9 | 2-Stroke | G–Y and 1986–2000 as listed |
| Suzuki | DT15K / DT15K1-K4 | 15 | 2-Stroke | G–Y and 2001–2004 as listed |
| Suzuki | DT20, DT25, DT30G-Y | 20–30 | 2-Stroke | 1986–2000 as listed |
| Suzuki | DT25, DT30K1-K2 | 25–30 | 2-Stroke | 2001–2002 as listed |
| Suzuki | DT40C-W G-X | 40 | 2-Stroke | 1986–1999 as listed |
| Suzuki | DT40W-K1-K4 | 40 | 2-Stroke | 2001–2004 as listed |
| Suzuki | DT55, DT65J-X | 55–65 | 2-Stroke | 1988–1999 as listed |
| Brand | Application | Rated HP | Stroke | Fitment Note |
|---|---|---|---|---|
| OMC / Johnson / Evinrude | J/BJ outboard applications | 70–140 | Confirm exact stroke | Supplier-listed application; verify model, year, and serial number |
Technical Specifications
- Product Type
- Marine outboard thermostat
- Opening Temperature
- 50°C (122°F)
- Application Range
- Selected Suzuki 25–70 HP applications and selected OMC, Johnson, and Evinrude 70–140 HP applications
- Installation
- Replacement installation in the original thermostat housing
- Product Construction
- Aftermarket replacement; material specification is not provided
- Gasket or O-Ring
- Not included unless specifically stated by the seller
What's in the Box
- 1 x 50°C (122°F) outboard thermostat
- Gasket or O-ring not included
Installation Notes
- Turn the engine off and allow it to cool completely before beginning service.
- Follow the engine manufacturer's service procedure for accessing the thermostat housing.
- Remove the housing cover and note the original thermostat orientation.
- Remove the old thermostat and inspect the housing, sealing surfaces, and related components for corrosion or damage.
- Clean the mating surfaces without damaging the housing.
- Install the replacement thermostat in the same orientation as the original part.
- Install a new gasket or O-ring if required by the engine service procedure; this product does not include one.
- Reinstall the housing cover and tighten the fasteners to the manufacturer's specified torque.
- Run the engine according to the service manual and check for leaks and proper cooling-system operation.
Troubleshooting & FAQ
What temperature is this thermostat rated for?
This thermostat is listed for a 50°C (122°F) opening temperature.
Is this thermostat an OEM part?
No. This listing is for an aftermarket replacement thermostat. The OEM and reference numbers are provided only to help identify compatible applications.
Does the thermostat include a gasket or O-ring?
No. The package contains one thermostat only. Replace the gasket or O-ring separately when required by the engine manufacturer's service procedure.
How do I confirm fitment?
Match the complete engine brand, model, horsepower, stroke, year or model code, and serial-number range where applicable. Also compare the original thermostat and its listed part number before ordering.
What are common symptoms of a faulty thermostat?
Possible symptoms include overheating, slow warm-up, unstable operating temperature, or improper cooling-system performance. Diagnose the complete cooling system before replacing the thermostat.
Safety & Important Information
- Never service a hot engine or pressurized cooling system.
- Verify the exact engine model, year or model code, horsepower, stroke, and serial number before purchase.
- Do not rely on a part number alone when multiple engine versions use different thermostats.
- This is an aftermarket replacement, not an OEM-branded component.
- Professional installation is recommended when the correct service procedure or torque specification is not available.
About Sea Sierra
Sea Sierra supplies aftermarket marine replacement parts for service and repair applications. Please contact support if you need help comparing the listed reference number with your original part.
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