143°F Thermostat for Johnson/Evinrude Outboards – Replaces 436195, 0436195

Product Details

This 143°F (62°C) marine thermostat is an aftermarket replacement for selected Johnson/Evinrude outboard cooling systems. It is intended for the applications listed below and replaces the specified original-equipment and aftermarket reference numbers.

The thermostat is designed to begin opening at approximately 143°F (62°C), helping the engine reach and maintain its intended operating temperature. Confirm the thermostat reference number and the complete engine application before ordering.

• 143°F (62°C) opening temperature.
• Aftermarket replacement thermostat for selected Johnson/Evinrude outboards.
• Application coverage includes selected 9.9–15 HP Big Bore, 40/48/50 HP, 3-cylinder, and 90° V4 engines.
• Thermostat only; no gasket or additional installation hardware is listed as included.

Part Number Matrix

The following numbers are reference identifiers associated with this replacement thermostat. Verify the number stamped on your original part or listed in your service information before purchase.

Engine Compatibility

Company fitment information identifies the following application groups. Because compatibility can vary by model designation and production configuration, match the engine model, year, stroke, and existing thermostat reference whenever possible.

Technical Specifications

Product Type

Marine engine thermostat

Product Configuration

Single replacement thermostat

Opening Temperature

143°F (62°C)

Application Brand

Johnson/Evinrude outboard applications listed above

Installation

Replacement installation in the existing thermostat housing

What's in the Box

• 1 x 143°F marine thermostat

Not included: A thermostat housing gasket, seals, or other installation hardware are not listed as included. Replace sealing components as required for your engine.

Installation Notes

1. Refer to the engine service information and allow the engine to cool completely before beginning work.
2. Disconnect the battery if required by the manufacturer's service procedure.
3. Locate the thermostat housing and place a suitable drain pan beneath the work area.
4. Remove the housing cover and note the orientation of the original thermostat.
5. Remove the old thermostat and clean loose corrosion or gasket material from the mating surfaces without damaging them.
6. Install the replacement thermostat in the same orientation as the original part.
7. Install a suitable new gasket or seal if required for your specific engine. The gasket is not listed as included with this product.
8. Reinstall the housing cover and tighten the fasteners according to the engine manufacturer's specified procedure and torque.
9. Run the engine according to the service procedure and inspect the housing area for leaks while monitoring engine temperature.

Troubleshooting & FAQ

Safety & Important Information

• Work only on a fully cooled engine and follow the engine manufacturer's service procedures.
• Do not rely on horsepower alone to confirm fitment; model, year, stroke, and engine configuration must also match.
• Inspect the cooling system for blockage, corrosion, leaks, and water-pump problems if the engine has experienced overheating.
• Professional installation is recommended when the correct procedure or torque specification is unavailable.

About Sea Sierra

• Marine Replacement Parts — Practical replacement components for selected marine applications.
• Application-Focused Listings — Reference numbers and fitment details are provided to support correct part selection.
• Installation Awareness — Always verify the complete engine application and replace related sealing components when required.