Marine Thermostat Kit 160°F – Fits OMC Cobra & Volvo Penta 3.8L-7.5L V6/V8 Engines (Replaces 383307, 3856961)

Marine Thermostat Kit 160°F – Fits OMC Cobra & Volvo Penta 3.8L-7.5L V6/V8 Engines

This 160°F (71°C) thermostat kit provides all the necessary components, including the thermostat and required gaskets, for a complete installation on a wide range of OMC Cobra and Volvo Penta marine engines. It is designed to restore proper engine operating temperature for optimal performance and efficiency.

Engine compatibility includes OMC Cobra 3.8L to 7.5L V6 and V8 sterndrive models (1969–1988) and Volvo Penta four-stroke V6/V8 engines (4.3L, 5.0L, 5.7L, 5.8L) across the GL, GS, Gi, FL, Fi, and FSi series.

• Engineered for direct OEM replacement, ensuring proper fit and function.
• Maintains a consistent engine temperature of 160°F (71°C).
• Kit includes one thermostat and all gaskets needed 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.

OMC Cobra (Sterndrive & Marine Engines)

Volvo Penta Marine Engines

Technical Specifications

Package Contents

• 1 x Thermostat (383307)
• 1 x O-ring (3852071)
• 1 x Gasket (314809)
• 1 x Gasket (313416)
• 1 x Housing Gasket (3852111)
• 1 x Installation Instructions (when included by manufacturer)

Installation Guide

1. Safety First: Ensure the engine is completely cool and disconnect the battery terminals.
2. Drain Coolant: Place a catch pan under the engine and carefully drain the cooling system.
3. Access Housing: Locate the thermostat housing. It is typically on top of the engine where the main coolant hose attaches. Remove any components blocking access.
4. Remove Old Thermostat: Unscrew the bolts holding the thermostat housing cover. Remove the cover and lift out the old thermostat and its gasket or O-ring.
5. Clean Surfaces: Thoroughly clean any old gasket material or corrosion from both the housing and the engine block mounting surfaces.
6. Install New Kit: Place the new thermostat into the housing, ensuring it is oriented correctly (spring side facing the engine). Position the new gasket or O-ring.
7. Reassemble: Re-attach the housing cover and tighten the bolts evenly to the manufacturer's recommended torque specification. Do not overtighten.
8. Refill and Check: Reconnect all hoses, close the drain plug, and refill the cooling system with the appropriate coolant. Start the engine and check for any leaks around the housing as it comes up to temperature.

Troubleshooting & FAQ

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

A: The best way is to match your existing part number to the ones listed in our cross-reference table. You can also check your engine model and year against the compatibility tables provided for OMC Cobra and Volvo Penta engines. When in doubt, visual comparison with your old part is recommended.

Q: What is the operating temperature of this thermostat?

A: This is a 160°F (71°C) thermostat, which is a standard temperature for many of the listed V6 and V8 marine engines.

Q: What parts are included in the kit?

A: The kit includes the thermostat itself, one O-ring, and three different gaskets to fit various housing applications. This ensures you have the correct components for a successful installation without needing to source parts separately.

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.