Sierra Thermostat Kit 18-3669 - Replaces OMC 396987 - Evinrude V-6 Crossflow Outboards

The Sierra Thermostat Kit 18-3669 is built for Evinrude V-6 Crossflow outboard engines and provides the components needed to restore proper cooling system temperature regulation. The kit is designed to work with thermostat 18-3543 and includes the thermostat components required for a complete, reliable repair rather than a single replacement part on its own.

Inside the kit, the thermostat identified as 18-3557 corresponds to O.E. Number 396987, giving buyers a direct cross-reference to the original equipment part it replaces. A second thermostat component, 18-2548, is also included as part of the kit contents, rounding out what is needed for the job. Because the parts are packaged together as a kit, installers do not need to source individual thermostats separately when servicing the cooling system on a compatible V-6 Crossflow outboard.

At 0.17 pounds, the kit is compact and easy to handle, making it a straightforward addition to routine outboard maintenance or a cooling system troubleshooting repair. This kit is intended specifically for Evinrude V-6 Crossflow applications, so confirming your engine matches this configuration before ordering is recommended.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-3669
• Product Name: Thermostat Kit
• Weight: 0.17 pounds
• UPC: 030999563071
• Compatible Thermostat: Uses thermostat 18-3543
• Kit Contents: Thermostat 18-3557 (O.E. 396987), Thermostat 18-2548

Fitment

• Evinrude V-6 Crossflow outboard engines

Replaces (OEM)

• 396987

Frequently Asked Questions

What engines is the Sierra 18-3669 thermostat kit designed for? This kit is designed for Evinrude V-6 Crossflow outboard engines and is built to work with thermostat 18-3543.

Does the 18-3669 kit replace an OEM part number? Yes, the thermostat included in this kit (Sierra 18-3557) corresponds to O.E. Number 396987, making 18-3669 a direct replacement option for that original equipment thermostat.

What is included in the Sierra 18-3669 thermostat kit? The kit contains two thermostat components: 18-3557, which corresponds to O.E. Number 396987, and 18-2548.

How much does the Sierra 18-3669 thermostat kit weigh? The kit weighs 0.17 pounds.

Is the 18-3669 kit compatible with thermostat 18-3543? Yes, this kit is specified to be used with thermostat 18-3543 on compatible V-6 Crossflow outboard engines.

Is this an aftermarket or genuine part? The 18-3669 kit is a Sierra-branded thermostat kit manufactured as a replacement part; it is not sold as a genuine OEM Evinrude part, though its included thermostat corresponds to OEM number 396987.

What is the UPC for the Sierra 18-3669 thermostat kit? The UPC for the Sierra Thermostat Kit 18-3669 is 030999563071.

Can I use this kit on any V-6 outboard engine? No, the 18-3669 kit is specified for Evinrude V-6 Crossflow outboard engines rather than V-6 outboards in general.

Does the kit include both thermostats needed for the engine? The 18-3669 kit includes two thermostat components, 18-3557 and 18-2548, packaged together for the applicable V-6 Crossflow outboard.

What category of part is the Sierra 18-3669? Sierra 18-3669 is a thermostat kit, part of the thermostats and gaskets category for outboard cooling system maintenance.