Cooling System | Suzuki Outboard

Pro Marine Aftermarket Cooling System Components

Pro Marine 17670 Thermostat - 60°C / 140°F

The Pro Marine 17670 Thermostat is a 60°C (140°F) aftermarket replacement thermostat for select Suzuki four-stroke outboard engines and Suzuki-based Johnson/Evinrude four-stroke outboards.

Compatible Suzuki applications include specified DF70A, DF75A, DF80A, DF90, DF90A, DF100, DF100B, DF100C, DF115, DF115B, DF140, DF140B, DF150, DF175, DF200, DF225, DF250 and DF300 engine families.

This thermostat replaces the specified Suzuki OEM 17670-90J00 and 17670-90J01 thermostat references and cross references Johnson/Evinrude 5033721 and 0769254.

The thermostat helps regulate engine operating temperature by controlling coolant flow through the outboard's cooling system. Maintaining the correct thermostat operation is important for proper engine warm-up and temperature regulation.

Product Information

• Pro Marine Part Number: 17670
• Brand: Pro Marine
• Product Type: Aftermarket Engine Thermostat
• Temperature Rating: 60°C / 140°F
• Suzuki OEM References: 17670-90J00, 17670-90J01
• Johnson/Evinrude References: 5033721, 0769254
• Engine Type: Four-Stroke Outboard
• Suzuki Applications: Select DF70-DF300 Engines
• Johnson/Evinrude Applications: Select 90-225 HP Four-Stroke Models
• Application: Engine Cooling System Temperature Regulation

OEM and Cross Reference Numbers

Pro Marine 17670 is an aftermarket replacement for the following specified OEM thermostat part numbers.

OEM numbers are provided for identification and cross-reference purposes. This product is a Pro Marine aftermarket replacement, not a Genuine Suzuki or Johnson/Evinrude OEM thermostat.

What This Part Is Used For

The thermostat is a temperature-controlled valve within the engine cooling system. It regulates the flow of cooling water as engine temperature changes during operation.

A properly functioning thermostat helps the engine reach and maintain its intended operating temperature. When the engine is cold, the thermostat restricts cooling water flow through the controlled passage. As temperature increases, the thermostat begins opening to permit additional cooling water flow.

Common Service Applications

• Replacement of a thermostat that is stuck open
• Replacement of a thermostat that is stuck closed
• Cooling system maintenance and inspection
• Engine operating temperature troubleshooting
• Thermostat replacement during engine service
• Cooling system repairs following overheating
• Marine repair shop and dealership maintenance

Important Fitment Information

This thermostat is not compatible with every Suzuki engine between 70 and 300 HP.

Suzuki uses different thermostat configurations across engine generations. The compatibility tables below distinguish earlier models, newer B-series engines, and model-specific identification references.

Temperature rating matters. This is a 60°C / 140°F thermostat. Confirm that the engine requires this temperature rating before ordering.

Always verify fitment using the complete engine model, identification number and applicable OEM parts diagram.

Compatible Suzuki Outboard Applications

The following tables summarize the specified Suzuki four-stroke applications. Production years are combined where consecutive, while individual model variations and identification references are retained.

Suzuki 70-140 HP Four-Stroke Outboards

Suzuki 150-300 HP Four-Stroke Outboards

Newer Suzuki Four-Stroke Applications - 2020-2026

The following applications retain the newer Suzuki model suffixes and identification references supplied for this thermostat. The year suffixes _020 through _026 correspond to the specified model-year designations and should not be interpreted as universal compatibility across all engines of the same horsepower.

The identification references above are retained from the supplied fitment information. They are not intended to establish unrestricted serial-number ranges or compatibility with unlisted engine variants.

Compatible Johnson and Evinrude Four-Stroke Applications

Pro Marine 17670 is also listed for the following Suzuki-based Johnson and Evinrude four-stroke engine models. The exact model numbers are retained to support accurate fitment identification.

Common Symptoms of a Faulty Thermostat

A thermostat that is stuck open, stuck closed, or not operating correctly may contribute to engine temperature problems.

• Engine operating temperature remaining unusually low
• Engine taking longer than normal to reach operating temperature
• Engine overheating when cooling water flow is restricted
• Inconsistent engine operating temperature
• Temperature-related warning indicators or alarms
• Corrosion or deposits affecting thermostat operation
• Thermostat valve sticking or failing to move properly

These symptoms can also result from water pump, cooling passage, sensor or other cooling system problems. Diagnose the cause before replacing parts.

Installation and Service Tips

Follow the applicable Suzuki or Johnson/Evinrude factory service manual when inspecting or replacing an engine thermostat.

• Verify the correct thermostat and 60°C / 140°F rating.
• Allow the engine to cool before opening the cooling system.
• Locate the thermostat housing using the OEM service manual.
• Inspect the existing thermostat for corrosion, deposits or sticking.
• Inspect the thermostat housing and sealing surfaces.
• Replace the thermostat gasket or seal when required.
• Install the thermostat in the correct orientation.
• Tighten housing fasteners to the manufacturer's specifications.
• Verify cooling water circulation after reassembly.
• Confirm normal engine operating temperature during testing.

Key Features and Benefits

• Pro Marine Aftermarket Replacement: An alternative to the original equipment thermostat for the specified applications.
• 60°C / 140°F Temperature Rating: Designed for applications requiring this thermostat temperature specification.
• Engine Temperature Regulation: Helps regulate cooling water flow as engine operating temperature changes.
• Broad Suzuki Application Coverage: Fits the specified DF70 through DF300 four-stroke engine models and generations.
• Johnson/Evinrude Compatibility: Fits the listed Suzuki-based 90 through 225 HP four-stroke outboard models.
• OEM Cross References: Associated with Suzuki 17670-90J00, 17670-90J01 and Johnson/Evinrude 5033721 and 0769254.
• Maintenance and Repair: Suitable for cooling system service where this thermostat is specified.

Frequently Asked Questions

Is Pro Marine 17670 a Genuine Suzuki thermostat?

No. This is a Pro Marine aftermarket replacement thermostat for the specified Suzuki and Johnson/Evinrude applications.

What temperature is this thermostat rated for?

The thermostat is rated at 60°C / 140°F. Confirm this is the correct temperature specification for your engine.

What Suzuki OEM numbers does this thermostat replace?

The supplied Suzuki cross references are 17670-90J00 and 17670-90J01.

What Johnson/Evinrude numbers cross reference this thermostat?

The supplied references include 5033721 and 0769254.

Does this thermostat fit Suzuki DF90 and DF90A?

Yes. The specified applications include older DF90 models and later DF90A, DF90AT and selected newer DF90 model variations.

Does it fit Suzuki DF115 and DF140?

Yes. The supplied fitment includes specified earlier DF115 and DF140 engines along with newer DF115B and DF140B model families.

Does it fit Suzuki DF150 and DF175?

Yes. The specified applications include DF150 and DF175 models from 2006-2011, along with listed TX and ZX variations from 2006-2007.

Does it fit Suzuki DF200, DF225 and DF250?

Yes. The supplied fitment includes specified DF200, DF225 and DF250 models and identification references, including selected newer T, Z and ST variations.

Does it fit Suzuki DF300?

Yes. The supplied applications include Suzuki DF300 models from 2007-2010. Other DF300 generations should be verified separately.

Does this thermostat fit newer Suzuki engines?

Yes. The supplied compatibility data includes specified 2020-2026 Suzuki engine model designations. Confirm the exact model suffix and engine identification before ordering.

Does it fit Johnson and Evinrude four-strokes?

Yes. It is listed for the specified Suzuki-based Johnson and Evinrude 90, 115, 140, 200 and 225 HP four-stroke engine models.

Can a bad thermostat cause overheating?

Yes. A thermostat that remains closed or does not open correctly can restrict cooling water flow and contribute to overheating. Other cooling system problems can produce similar symptoms.

Can a thermostat stuck open cause problems?

Yes. A thermostat that remains open may prevent the engine from reaching its intended operating temperature under some conditions.

Is a thermostat gasket included?

Check the product listing or contact Pro Marine USA to confirm included components. Replace associated seals or gaskets as required by the factory service procedure.

How do I verify fitment?

Use the complete engine model and identification number to confirm the correct OEM thermostat in the applicable parts diagram.

Dealer Discounts & Store Policies

Wholesale Marine Parts Pricing

Pro Marine USA supplies Pro Marine aftermarket parts along with Genuine Mercury, Yamaha, Suzuki, BRP and Tohatsu marine engine parts for professional marine repair shops, dealerships, technicians and retail customers.

Qualified marine businesses can apply for a Pro Marine dealer account to access wholesale pricing on eligible parts.

Apply for Dealer Pricing

Shipping Information

• Free shipping on qualifying orders over $100 within the continental United States. Oil and oversized items are excluded.
• In-stock orders placed before 5:30 PM EST ship the same business day, Monday-Friday.
• Shipping options are available through UPS, USPS and FedEx.
• Typical delivery time is 1-5 business days, depending on destination and shipping service.

30-Day Return Policy

• Eligible returns are accepted within 30 days.
• Parts must be new, unused and in original packaging.
• Installed parts are not returnable.
• OEM electrical items are not returnable.
• Return authorization is required before returning merchandise.

Need Help Confirming Fitment?

If you are unsure whether Pro Marine 17670 is correct for your Suzuki or Johnson/Evinrude outboard, contact Pro Marine USA with the complete engine model and identification information.

Contact Pro Marine USA or call 941-721-3000.

Searchable Part Numbers

17670, 17670-90J00, 1767090J00, 17670-90J01, 1767090J01, 5033721, 0769254, 769254

Searchable Terms

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