Sierra 18-3648 Thermostat Kit, 160 Degree, for MerCruiser 4.3L, 4.3 LX (262 CID) V-6

The Sierra 18-3648 Thermostat Kit is a complete thermostat replacement kit built for MerCruiser 4.3L and 4.3 LX (262 CID) V-6 sterndrive engines, model 205, serial number F001220 and up. It is designed for engines using a single and 3-point drain system. The kit supplies everything needed to restore correct engine operating temperature in one purchase, rather than sourcing the thermostat and gaskets separately.

Inside the kit is an 18-3649 thermostat rated to open at 160 degrees Fahrenheit, along with an 18-2553 thermostat cover gasket and an 18-2917 thermostat gasket, so the sealing surfaces are replaced along with the thermostat itself for a proper seal on installation. The thermostat housing is white in color. Sierra engineers and manufactures its cooling system parts to meet or exceed the original equipment part it replaces, giving boat owners a dependable, correctly-calibrated replacement without going through a dealer for OEM parts.

This kit cross-references directly to Mallory 9-43100, making it easy to confirm as the correct replacement when comparing part numbers. It is intended for MerCruiser 4.3L V-6 (262 CID) inboard/outboard engines within the specified serial number range.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-3648
• Product Name: Thermostat Kit
• Color: White
• Temperature Rating: 160 degrees Fahrenheit
• Kit Contents: 18-3649 Thermostat, 18-2553 Thermostat Cover Gasket, 18-2917 Thermostat Gasket
• Weight: 0.18 pounds
• UPC: 808282258825

Fitment

• MerCruiser 4.3L, 4.3 LX (262 CID) V-6, Model 205, Serial Number F001220 and Up, single and 3-point drain system

Replaces (OEM)

• Mallory 9-43100

Frequently Asked Questions

What does the Sierra 18-3648 Thermostat Kit include? The kit includes an 18-3649 thermostat rated at 160 degrees Fahrenheit, an 18-2553 thermostat cover gasket, and an 18-2917 thermostat gasket.

What engines does the 18-3648 thermostat kit fit? It fits MerCruiser 4.3L and 4.3 LX (262 CID) V-6 engines, model 205, serial number F001220 and up, with a single and 3-point drain system.

What temperature does the thermostat open at? The thermostat included in the 18-3648 kit is rated to open at 160 degrees Fahrenheit.

Is the Sierra 18-3648 kit interchangeable with any other brand? Yes, the 18-3648 thermostat kit cross-references directly to Mallory 9-43100.

How much does the 18-3648 thermostat kit weigh? The Sierra 18-3648 Thermostat Kit weighs 0.18 pounds.

What color is the 18-3648 thermostat housing? The Sierra 18-3648 Thermostat Kit is white.

Do I need to replace the gaskets when installing a new thermostat? Yes, the 18-3648 kit comes with both an 18-2553 thermostat cover gasket and an 18-2917 thermostat gasket so the sealing surfaces are renewed along with the thermostat.

Is the Sierra 18-3648 an OEM-equivalent part? Sierra manufactures the 18-3648 Thermostat Kit to meet or exceed the original equipment part it replaces.

What serial number range applies to this thermostat kit? The Sierra 18-3648 Thermostat Kit applies to MerCruiser 4.3L (262 CID) V-6 engines with serial number F001220 and up.

Does the 18-3648 kit work on a MerCruiser with a 3-point drain system? Yes, the 18-3648 Thermostat Kit is designed for MerCruiser 4.3L V-6 (262 CID) engines with a single and 3-point drain system.