Sierra 18-2193 Rear Engine Mount, Replaces Mercury Marine 99297A1, Fits Alpha and Bravo Drives

The Sierra 18-2193 Rear Engine Mount is a machined rear engine mount built to support MerCruiser sterndrive engines through the rear of the flywheel housing. It is engineered as a direct replacement for the OEM rear mount, providing the correct mounting interface for engines paired with Alpha and Bravo drives. Rear engine mounts absorb engine vibration and torque loading while holding the block securely in place at the transom end, so a worn, cracked, or collapsed mount can lead to excess vibration, misalignment, or drivetrain stress if left unaddressed.

This mount is manufactured with a machined exterior finish for a precise, consistent fit against the mounting hardware. It is designed to fit MCM flywheel housings used with Alpha and Bravo drives, and covers a broad range of MerCruiser applications including 120/140 HP engines from S/N 6229717 and up, all 224 CID blocks, 200, 228, 230, 260, 300, and 320 HP engines, and all 350-454 Magnum engines. Sierra parts are backed by Sierra's customer satisfaction warranty, giving boat owners a dependable aftermarket option when the original engine mount needs replacement.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-2193
• Category: Mercruiser Gearcase & Drive Parts
• UPC: 030999562517
• Weight: 0.16 pounds
• Product Dimensions: 0.39 x 0.39 x 0.39 inches
• Exterior Finish: Machined
• Drive Compatibility: MCM flywheel housing with Alpha and Bravo drives
• OEM Cross Reference: 33149, 99297A1, 99297A2

Fitment

• 120/140 HP, S/N 6229717 & up
• All 224 CID blocks
• All 898, 200, 228, 230, 260, 300 & 320 HP engines
• All 350-454 Magnum engines
• MCM flywheel housing with Alpha and Bravo drives

Replaces (OEM)

• 33149
• 99297A1
• 99297A2

Frequently Asked Questions

What engines does the Sierra 18-2193 rear engine mount fit? The Sierra 18-2193 fits 120/140 HP engines from S/N 6229717 and up, all 224 CID blocks, 200, 228, 230, 260, 300, and 320 HP engines, and all 350-454 Magnum engines with an MCM flywheel housing paired with Alpha or Bravo drives.

Is the 18-2193 mount compatible with Alpha and Bravo drives? Yes, the Sierra 18-2193 rear engine mount is designed for MCM flywheel housings used with both Alpha and Bravo drives.

Which OEM part numbers does the Sierra 18-2193 replace? This rear engine mount replaces OEM numbers 33149, 99297A1, and 99297A2.

Is the Sierra 18-2193 the same as Mercury Marine 99297A1? The Sierra 18-2193 is an aftermarket equivalent to Mercury Marine 99297A1 and is built to replace that OEM part directly.

What finish does the 18-2193 rear engine mount have? It has a machined exterior finish for a precise fit at the mounting interface.

How much does the Sierra 18-2193 rear engine mount weigh? The Sierra 18-2193 weighs 0.16 pounds.

What are the dimensions of the 18-2193 rear engine mount? The rear engine mount measures 0.39 x 0.39 x 0.39 inches.

Does a worn rear engine mount need to be replaced? Yes, a worn, cracked, or collapsed rear engine mount like the position filled by the Sierra 18-2193 should be replaced to prevent excess vibration and misalignment at the flywheel housing.

Is the Sierra 18-2193 covered by a warranty? The Sierra 18-2193 rear engine mount is covered under Sierra's customer satisfaction warranty.

Does the 18-2193 fit 224 CID block engines? Yes, the Sierra 18-2193 rear engine mount fits all 224 CID blocks.

Does the 18-2193 fit 350-454 Magnum engines? Yes, this rear engine mount fits all 350-454 Magnum engines.