Thermostat for Suzuki DF2.5, DF4, DF5, DF6, DF9.9B, DF15A & DF20A 4-Stroke Outboards – Replaces 17670-91J00, 17670-91J01, 17670-91J02 & Johnson/Evinrude 5033385
Thermostat for Suzuki DF2.5, DF4, DF5, DF6, DF9.9B, DF15A & DF20A 4-Stroke Outboards – Replaces 17670-91J00, 17670-91J01, 17670-91J02 & Johnson/Evinrude 5033385 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 for Suzuki DF2.5, DF4, DF5, DF6, DF9.9B, DF15A & DF2...
Thermostat for Suzuki DF2.5, DF4, DF5, DF6, DF9.9B, DF15A & DF20A 4-Stroke Outboards – Replaces 17670-91J00, 17670-91J01, 17670-91J02 & Johnson/Evinrude 5033385 is backordered and will ship as soon as it is back in stock.
Product Details
This aftermarket 122°F (50°C) thermostat is listed for Suzuki 4-stroke outboard engines including the DF2.5, DF4, DF5, DF6, DF9.9B, DF15A and DF20A. The Suzuki applications listed by the manufacturer are DF2.5 models from 2006, DF4/DF5/DF6 models from 2002 onward, and DF9.9B/DF15A/DF20A models from 2013 onward.
It is also listed as a replacement for Johnson/Evinrude/OMC thermostat part number 5033385, including applicable 2, 4 and 5 HP outboard applications. Always confirm the original thermostat number and the complete engine model before ordering.
- Aftermarket replacement thermostat for specified outboard applications.
- Temperature rating: 122°F (50°C).
- Helps regulate engine operating temperature within the range specified for the listed applications.
Part Number Matrix
Use the following manufacturer part numbers to compare the thermostat in your engine before purchase.
| Brand | Manufacturer or Reference Part Number |
|---|---|
| Suzuki | 17670-91J00, 17670-91J01, 17670-91J02 |
| Johnson/Evinrude/OMC | 5033385 |
| Aftermarket reference | 18-S91J |
Engine & Model Compatibility
Fitment is based on the engine model, year, stroke and original thermostat number. Verify all applicable details before installation.
| Brand | Model | Rated HP | Stroke | Year or Year Range | Reference Part No. | Notes |
|---|---|---|---|---|---|---|
| Suzuki | DF2.5 | 2.5 | 4-Stroke | 2006 | 17670-91J00, 17670-91J01, 17670-91J02 | Confirm the exact model designation and serial range. |
| Suzuki | DF4 | 4 | 4-Stroke | 2002 and newer | 17670-91J00, 17670-91J01, 17670-91J02 | Confirm the original thermostat number. |
| Suzuki | DF5 | 5 | 4-Stroke | 2002 and newer | 17670-91J00, 17670-91J01, 17670-91J02 | Confirm the original thermostat number. |
| Suzuki | DF6 | 6 | 4-Stroke | 2002 and newer | 17670-91J00, 17670-91J01, 17670-91J02 | Confirm the original thermostat number. |
| Suzuki | DF9.9B | 9.9 | 4-Stroke | 2013 and newer | 17670-91J00, 17670-91J01, 17670-91J02 | Confirm the exact model and year. |
| Suzuki | DF15A | 15 | 4-Stroke | 2013 and newer | 17670-91J00, 17670-91J01, 17670-91J02 | Confirm the exact model and year. |
| Suzuki | DF20A | 20 | 4-Stroke | 2013 and newer | 17670-91J00, 17670-91J01, 17670-91J02 | Confirm the exact model and year. |
| Johnson/Evinrude/OMC | Applicable models using 5033385 | 2, 4 or 5 | As specified for the engine | Model- and year-specific | 5033385 | Match the original thermostat number and engine model before ordering. |
Technical Specifications
- Product Type
- Outboard engine thermostat
- Temperature Rating
- 122°F (50°C)
- Construction
- Aftermarket replacement component
- Installation
- Replacement installation; follow the engine service manual
- Fuel Type
- Gasoline outboard applications
What’s in the Box
- 1 x 122°F (50°C) outboard engine thermostat
Gaskets, seals and additional hardware are not listed as included. Reuse or replace related sealing components according to the engine service manual.
Installation Notes
- Allow the engine to cool completely and follow the safety procedures in the service manual.
- Disconnect the battery if required by the engine manufacturer before beginning work.
- Locate the thermostat housing and place a suitable drain pan beneath the work area.
- Remove the housing cover carefully and note the orientation of the old thermostat.
- Remove the old thermostat and inspect the housing, sealing surfaces and related gasket or seal.
- Clean the mating surfaces without damaging them.
- Install the new thermostat in the orientation specified by the engine service manual.
- Install the required gasket or seal, refit the housing cover and tighten the fasteners to the manufacturer’s specified torque.
- Restore the cooling-water supply, reconnect the battery if applicable, run the engine according to the service procedure and check for leaks and proper water flow.
Troubleshooting & FAQ
How do I confirm fitment for my engine?
Match your engine brand, model, horsepower, stroke and year to the compatibility information above, then compare the thermostat in your engine with the listed manufacturer part number. If the model or original part number differs, consult the engine service manual or a qualified marine technician.
What is the temperature rating?
The manufacturer lists this thermostat at 122°F (50°C).
What are common signs of a thermostat problem?
Possible symptoms include abnormal operating temperature, overheating, running cooler than intended, inconsistent temperature behavior or an engine warning. Check the cooling system and follow the manufacturer’s diagnostic procedure before replacing parts.
Does this listing include a gasket?
The package contents list one thermostat only. A gasket or seal is not listed as included, so inspect the existing component and obtain the correct replacement if required by the service procedure.
Is this an OEM part?
No. This is an aftermarket replacement thermostat. The listed manufacturer part numbers are reference numbers used to help confirm application.
How often should the thermostat be replaced?
Follow the maintenance schedule and inspection procedure in your engine service manual. Replacement may also be necessary when testing shows incorrect operation or when the thermostat has been affected by contamination, corrosion or overheating.
Safety & Important Information
- Verify the complete engine model, year, stroke and original thermostat number before purchase.
- Do not rely on horsepower alone to confirm fitment.
- Use the correct gasket or seal and follow the manufacturer’s torque and installation instructions.
- This is an aftermarket replacement component, not an OEM part.
- Professional installation is recommended when the correct procedure or engine-specific requirements are unknown.
About Sea Sierra
- Marine Replacement Parts — We supply aftermarket components for common marine repair and maintenance applications.
- Application-Focused Information — Product details are organized around manufacturer part numbers and engine fitment information.
- Support for Installation Planning — Always compare the original component and consult the engine service manual before installation.
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