160° Thermostat Kit – Fits MerCruiser V6 & V8 4.3L-8.2L Engines (Replaces 807252Q5)

160° Thermostat Kit – Fits MerCruiser V6 & V8 4.3L-8.2L Engines (Replaces 807252Q5)

This 160°F (71°C) thermostat kit is designed for MerCruiser inboard and sterndrive engines with V6 and V8 configurations from 1987 and newer. It is primarily intended for 4.3L, 5.0L, 5.7L, and 7.4L/8.2L engines used in raw water cooled systems.

This kit serves as a direct replacement for multiple OEM and aftermarket part numbers, ensuring a precise fit and reliable performance for compatible models.

• Operating Temperature: Opens at 160°F (71°C) to maintain optimal engine temperature.
• Complete Kit: Includes thermostat, plastic sleeve, gaskets, and an O-ring for a full installation.
• Installation Type: Direct replacement for a straightforward installation process.

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 x Thermostat (807252T2/8072522/8052732)
• 1 x O-ring (25-30224/25-27018)
• 1 x Gasket (27-331792/27-331791)
• 1 x Gasket (27-41812/27-09556)
• 1 x Gasket (27-47510)
• 1 x Gasket (27-33918)
• 1 x Gasket (27-530451/27-53045/27-33179)
• 1 x Plastic Housing Sleeve (23-806922)

Installation Guide

1. Drain the Coolant: Ensure the engine is cool. Place a container under the engine block or heat exchanger and drain the coolant to a level below the thermostat housing.
2. Locate and Open Housing: Locate the thermostat housing, which is typically on top of the engine where the main coolant hose connects. Remove the bolts securing the housing cover.
3. Remove Old Thermostat: Carefully lift the housing cover. Note the orientation of the old thermostat and remove it, along with the old gasket or O-ring.
4. Clean Surfaces: Clean both the housing and cover mating surfaces thoroughly, removing all old gasket material and corrosion.
5. Install New Thermostat: Place the new thermostat into the housing, ensuring it is in the correct orientation. Install the new gasket and/or O-ring as supplied in the kit.
6. Reassemble and Refill: Reattach the housing cover and tighten the bolts to the manufacturer's specified torque. Refill the cooling system with the appropriate coolant.
7. Check for Leaks: Start the engine and let it warm up. Carefully check for any leaks around the thermostat housing and ensure the engine reaches its normal operating temperature.

Troubleshooting & FAQ

Q: How do I confirm this thermostat kit fits my specific engine?

A: The best way to ensure compatibility is to check the "Compatible Engine Models" table on this page. Match your engine's model, year, and especially the serial number range against the listed values. Cross-referencing your old part number with our "Part Number Cross-Reference" table also helps confirm the fit.

Q: What are the common signs of a failing thermostat?

A: A faulty thermostat can cause several issues, including engine overheating (if stuck closed) or the engine taking too long to reach operating temperature (if stuck open). You might notice erratic temperature gauge readings or poor engine performance.

Q: What temperature does this thermostat open at?

A: This is a 160°F (71°C) thermostat. It is designed to start opening at this temperature to allow coolant to circulate and maintain the engine in its optimal temperature range for raw water cooled systems.

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.