8M0093561 Thermostat 80°C for Mercruiser 2.8L 4.2L EI ES EJ QSD | JLM Marine

Thermostat 80°C for Mercruiser 2.8L 4.2L EI ES EJ QSD Engines

This 80°C thermostat is designed for Mercruiser Inboard and Stern Drive engines, including 2.8L EI, ES, EJ, and QSD models (170–230 HP) as well as 4.2L QSD engines (270–350 HP). It ensures optimal operating temperature for reliable performance across a wide range of Mercruiser diesel and gasoline applications.

This aftermarket replacement directly replaces Mercruiser part numbers 8M0093561, 879194215, 879194233, 879194231, and 896332148, providing a cost-effective solution without compromising quality.

• Precision-engineered to OEM specifications for accurate temperature control
• Suitable for both inboard and stern drive configurations
• Fits multiple engine families for broad compatibility

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.

Technical Specifications

Package Contents

• 1 × Thermostat 80°C (8M0093561)

Installation Guide

1. Allow the engine to cool completely before beginning work. Relieve system pressure by carefully removing the coolant cap.
2. Locate the thermostat housing on your engine and drain a sufficient amount of coolant into a clean container.
3. Remove the bolts securing the thermostat housing cover and lift it away to expose the old thermostat.
4. Carefully remove the old thermostat and clean all gasket material from both the housing and cover mating surfaces.
5. Install the new 80°C thermostat in the correct orientation (spring side typically faces the engine block). Ensure it seats properly in the recess.
6. Place a new gasket or apply the appropriate sealant to the housing surface as specified by your engine's service manual.
7. Reinstall the thermostat housing cover and tighten bolts to the manufacturer's recommended torque specification in a criss-cross pattern.
8. Refill the cooling system with the proper coolant mixture and bleed any air from the system per manufacturer instructions.
9. Start the engine and allow it to reach operating temperature while monitoring for leaks around the thermostat housing.
10. Check coolant level after the engine has cycled and top off as necessary.

Troubleshooting & FAQ

Q: How do I confirm this thermostat fits my Mercruiser engine?
A: Cross-reference your engine model with the Compatible Engine Models table above. Verify that your current thermostat matches OEM part number 8M0093561, 879194215, 879194233, 879194231, or 896332148.

Q: What are the signs that my thermostat needs replacement?
A: Common symptoms include engine overheating, slow warm-up times, fluctuating temperature gauge readings, or coolant leaks around the thermostat housing. If your engine runs too hot or too cold, the thermostat may be stuck closed or open.

Q: How often should I replace my marine thermostat?
A: Marine thermostats should typically be inspected during annual service and replaced every 3–5 years or whenever you notice temperature regulation issues. Saltwater and harsh marine environments can accelerate wear.

Q: Will this 80°C thermostat affect my engine performance compared to the original?
A: No, this thermostat is manufactured to OEM specifications with the same 80°C opening temperature. It will maintain the same operating temperature range as your factory part.

Q: 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.

Q: 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.

Q: 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.