Thermostat Kit – Fits Mercury/Mariner 75-150 HP 4-Stroke EFI Outboards

Thermostat Kit – Fits Mercury/Mariner 75-150 HP 4-Stroke EFI OutboardsThermostat Kit Fits Mercury Mariner 75 150 HP 4 Stroke EFI Outboards (Replaces 892864T06, 892864A06) This thermostat kit is a direct fit replacement for Mercury Mariner 75 150 HP 4 Stroke EFI outboards (2001 2014). It is designed for models with serial numbers 1B366823 2B094995 (75 115 HP) and 1B905505 & Up (150 HP). This assembly replaces Mercury part numbers 892864T06, 8M0090819, and 892864A06, as well as Sierra part number 18 3635 K. It provides a

Thermostat Kit – Fits Mercury/Mariner 75-150 HP 4-Stroke EFI Outboards (Replaces 892864T06, 892864A06)

This thermostat kit is a direct-fit replacement for Mercury/Mariner 75-150 HP 4-Stroke EFI outboards (2001-2014). It is designed for models with serial numbers 1B366823-2B094995 (75-115 HP) and 1B905505 & Up (150 HP).

This assembly replaces Mercury part numbers 892864T06, 8M0090819, and 892864A06, as well as Sierra part number 18-3635-K. It provides a reliable solution for maintaining optimal engine operating temperature.

• Includes the complete assembly with housing, thermostat, O-ring, and clamp.
• Engineered for a direct-fit OEM replacement installation.
• Rated for a 48.8°C/50°C (120°F) operating temperature.

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 Mercury owners, here’s a guide to help you identify your engine’s serial/model: Mercury Serial Number Guide. You can also review exploded diagrams to verify part numbers: Mercury Parts Diagrams & Catalog.

Technical Specifications

Package Contents

• 1 x Thermostat Assembly with Housing (892864T06/8M0090819)
• 1 x O-ring Seal (8M005958)
• 1 x Clamp (888988008)

Installation Guide

1. Safety First: Ensure the engine is off and cool. Disconnect the battery cables.
2. Drain Coolant: Place a container under the engine and drain the cooling system to a level below the thermostat housing.
3. Locate Housing: Identify the thermostat housing on the engine block.
4. Remove Old Assembly: Loosen the clamp and detach the hose. Remove the bolts securing the housing and carefully lift it away.
5. Clean Surface: Thoroughly clean the mating surface on the engine block, removing any old gasket or sealant residue.
6. Install New Thermostat: Place the new thermostat into the housing, ensuring it is correctly oriented. Install the new O-ring seal.
7. Reassemble: Mount the new housing assembly onto the engine block and tighten the bolts to the manufacturer's specified torque.
8. Reconnect Hose: Reattach the coolant hose and secure it with the new clamp.
9. Refill & Check: Refill the cooling system with the appropriate coolant. Start the engine and carefully check for any leaks around the housing.
10. Final Test: Allow the engine to reach operating temperature, monitoring the temperature gauge to ensure it is stable and within the correct range.

Troubleshooting & FAQ

How do I confirm this fits my engine?

Check the compatible models table and verify your engine's serial number falls within the specified range for your model, year, and horsepower. Cross-referencing the part number (892864T06) with your service manual is also recommended.

What temperature does this thermostat operate at?

This thermostat is rated for 48.8°C/50°C (120°F) to ensure your engine maintains its optimal operating temperature for performance and efficiency.

What are common signs of a failing thermostat?

Signs of a faulty thermostat include engine overheating, the engine not reaching normal operating temperature (running too cool), erratic temperature gauge readings, poor engine performance, or increased fuel consumption.

Is this a complete kit for installation?

Yes, this is a complete kit that includes the thermostat, the housing assembly, the required O-ring seal, and the clamp, providing all the necessary components for a standard replacement.

OEM vs. Aftermarket?

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?

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?

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.