Sierra 18-7748 Carburetor Kit for 5.7L Mercruiser Alpha 350 V-8 Weber 9665S Carburetors

The Sierra 18-7748 Carburetor Kit is a carburetor rebuild kit built to service Weber 9665S carburetors used on 5.7L Alpha 350 cubic inch V-8 marine engines. It is designed for engines falling within two specific serial number ranges: F000455 to F273497 (1993-1994) and F273498 to F600999 (1994-1995). The kit is also compatible with MCM/MIE/Tow Sports 350 Mag and 5.7L/LX engines running 9665 and 9781 Weber carburetors, and with MCM/MIE 454 Mag 7.4L and 8.2L engines.

Because carburetors wear internally long before the outer housing does, a rebuild kit restores correct fuel metering and idle performance without the expense of a full carburetor replacement. The 18-7748 kit corresponds directly to the original Weber carburetor part numbers used on these engines and cross-references to a wide range of Carter/Weber, Mallory, and Mercruiser OEM carburetor numbers, making it straightforward to match against an existing carburetor tag or an old kit part number.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-7748
• Product Type: Carburetor Rebuild Kit
• Carburetor Compatibility: Weber 9665S (also fits 9665 and 9781 Weber carburetors)
• Engine Compatibility: 5.7L Alpha 350 V-8; MCM/MIE 350 Mag and 5.7L/LX engines; MCM/MIE 454 Mag 7.4L and 8.2L engines
• Serial Number Range (1993-1994): F000455 to F273497
• Serial Number Range (1994-1995): F273498 to F600999
• Weight: 0.3 pounds
• Unit Count: 1 kit

Fitment

• 5.7L Alpha 350 V-8, serial numbers F000455 to F273497 (1993-1994), Weber 9665S carburetor
• 5.7L Alpha 350 V-8, serial numbers F273498 to F600999 (1994-1995), Weber 9665S carburetor
• MCM/MIE/Tow Sports 350 Mag and 5.7L/LX engines with 9665 and 9781 Weber carburetors
• MCM/MIE 454 Mag 7.4L and 8.2L engines

Replaces (OEM)

• 3310-806761A1
• 3310-806761A3
• Carter/Weber 9600, 9662, 9663, 9665, 9666, 9772, 9773, 9774, 9776, 9777, 9780, 9782, 9665S, 9772SA, 9776S, 9776SA, 9776SB, 9779S, 9780S
• Mallory 9-37639
• Mercruiser 809064, 8M0120193, 808697

Frequently Asked Questions

What does the Sierra 18-7748 carburetor kit fit? The Sierra 18-7748 fits 5.7L Alpha 350 V-8 engines with a Weber 9665S carburetor in two serial number ranges: F000455 to F273497 (1993-1994) and F273498 to F600999 (1994-1995). It also fits MCM/MIE/Tow Sports 350 Mag and 5.7L/LX engines with 9665 and 9781 Weber carburetors, and MCM/MIE 454 Mag 7.4L and 8.2L engines.

How do I know if my engine falls in the correct serial number range for 18-7748? Check the serial number tag on your engine block: the 18-7748 kit covers F000455 through F273497 for 1993-1994 engines and F273498 through F600999 for 1994-1995 engines. If your serial number falls outside these ranges, a different Sierra carburetor kit will be the correct match.

Is the 18-7748 kit compatible with OEM Weber and Mercruiser carburetor part numbers? Yes, the 18-7748 kit cross-references to original Weber carburetor part numbers 3310-806761A1 and 3310-806761A3, along with Mercruiser numbers 809064, 8M0120193, and 808697.

Does this kit work with Carter/Weber carburetor model numbers other than 9665S? The 18-7748 kit is also listed as compatible with a range of Carter/Weber carburetor models including 9600, 9662, 9663, 9665, 9666, 9772, 9773, 9774, 9776, 9777, 9780, 9782, 9772SA, 9776S, 9776SA, 9776SB, 9779S, and 9780S.

How much does the Sierra 18-7748 carburetor kit weigh? The Sierra 18-7748 carburetor kit weighs 0.3 pounds.

Will this kit fit a 454 Mag engine? Yes, in addition to 5.7L Alpha 350 V-8 applications, the 18-7748 kit fits MCM/MIE 454 Mag 7.4L and 8.2L engines.

Is Mallory carburetor part 9-37639 covered by this Sierra kit? Yes, Mallory part number 9-37639 is one of the OEM cross-reference numbers covered by the Sierra 18-7748 carburetor kit.

Is the Sierra 18-7748 an OEM part or an aftermarket kit? The 18-7748 is a Sierra-manufactured aftermarket carburetor rebuild kit engineered to service and cross-reference the original Weber 9665S carburetor and related OEM carburetor part numbers.

Does the Sierra 18-7748 carburetor kit come with a warranty? Yes, the 18-7748 carburetor kit is covered under Sierra's customer satisfaction warranty, as are all Sierra parts.

What is included with the Sierra 18-7748 carburetor kit? The Sierra 18-7748 is supplied as a single carburetor rebuild kit, sold as one unit count, for servicing the applicable Weber carburetor.