Marine Thermostat 143° – Fits Johnson/Evinrude Outboard Motors (Replaces 436195)

Marine Thermostat 143° – Fits Johnson/Evinrude Outboard Motors (Replaces 436195)

This thermostat is designed to fit a wide range of Johnson/Evinrude 2-Stroke outboard engines from 5 to 300 HP (1993–2007) and select Yamaha 30–40 HP 4-Stroke models. It ensures your engine maintains the correct operating temperature for optimal performance and fuel efficiency.

This component is a direct replacement for multiple OEM and aftermarket part numbers, including BRP 0436195, 436195, 0777837; Sierra 18-79970, 18-3561; Mallory 9-43023; GLM 13150; and Yamaha 6BG-13915-00-00.

• Operating Temperature: Opens at a factory-set 143°F (61.7°C).
• Installation Type: Direct replacement for a hassle-free installation.
• Included Parts: Comes with one thermostat ready for installation.

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Compatible Engine Models

Confirm your engine model/year in the table below. For Johnson/Evinrude owners, here’s a guide to help you identify your engine’s serial/model: Johnson/Evinrude Serial Number Guide.

Confirm your engine model/year in the table below. For Yamaha owners, here’s a guide to help you identify your engine’s serial/model: Yamaha Serial Number Guide. You can also review exploded diagrams to verify part numbers: Yamaha Parts Diagrams & Catalog.

Technical Specifications

Package Contents

• 1 x Thermostat (436195)

Installation Guide

1. Disconnect Battery: Ensure the engine is off and disconnect the negative battery terminal.
2. Drain Coolant: Drain the engine cooling system into a suitable container.
3. Locate Housing: Find the thermostat housing, typically on the top of the engine or near the cylinder heads.
4. Remove Cover: Loosen and remove the bolts securing the thermostat housing cover.
5. Remove Old Thermostat: Carefully lift out the old thermostat and its gasket or seal.
6. Clean Surfaces: Thoroughly clean the mating surfaces of the housing and its cover, removing any old gasket material or corrosion.
7. Install New Thermostat: Place the new thermostat into the housing, ensuring it is oriented correctly.
8. Replace Cover: Position the new gasket, replace the housing cover, and hand-tighten the bolts.
9. Torque Bolts: Tighten the bolts evenly to the manufacturer's recommended torque specification.
10. Refill Coolant: Refill the cooling system with the appropriate coolant.
11. Reconnect Battery: Reconnect the negative battery terminal.
12. Check for Leaks: Start the engine, let it reach operating temperature, and carefully check for any coolant leaks around the housing.

Troubleshooting & FAQ

How do I confirm this fits my engine?

A: First, check the Part Number Cross-Reference table to see if your old part number is listed. Next, review the Compatible Engine Models table to find your engine's HP, stroke, and year range. For precise verification, use the linked serial number guides to match your exact model.

What are the signs of a failing thermostat?

A: Common signs of a faulty thermostat include the engine overheating, running too cool and never reaching normal operating temperature, erratic temperature gauge readings, increased fuel consumption, or poor overall engine performance.

How often should I replace my outboard's thermostat?

A: For preventative maintenance, it is recommended to inspect your thermostat annually and replace it every 2-3 years or approximately 300 hours of use. Always replace it immediately if you notice any signs of failure.

OEM vs. Aftermarket?

A: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

How fast do you ship and how much does it cost?

A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

What is your warranty and return policy?

A: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.