MERCURY Mag Engine Flywheel Wheel 7.4 3973457N

( Manufacturer Part Number: 3973457 ), ( Part Type: Engine Flywheel Wheel ), ( Country/region Of Manufacture: United States )

Review MERCURY 7.4 Mag Engine Flywheel Fly Wheel fits MERCRUISER MAGNUM MARINE 454

Introducing the Mercury 7.4 454 Magnum Marine Engine Flywheel (Part Number: 3973457), a high-performance component designed specifically for Mercury's 7.4 liter big-block engines. This flywheel is an essential component of your marine engine's powertrain system, responsible for transferring engine power to the propeller shaft.

Crafted from robust materials, the Mercury 3973457 flywheel is engineered to withstand the rigors of marine applications. It features a heavy-duty steel construction, ensuring durability and reliability even in the harshest marine environments. The flywheel's machined surface is precisely balanced to minimize vibration and optimize power transmission, contributing to a smoother and more efficient operation of your marine engine.

The Mercury 3973457 flywheel is a direct fit for Mercury 7.4 454 Magnum engines. Its dimensions and mounting pattern are specifically designed to match the engine's original flywheel, ensuring a seamless installation process. The flywheel also comes with a new clutch assembly, making it a complete solution for clutch replacement in your marine engine.

Installing the Mercury 3973457 flywheel is a straightforward process, thanks to its precise manufacturing and fitment. The flywheel comes with clear installation instructions to guide you through the process. It is important to note that the installation should be carried out by a qualified marine mechanic to ensure safety and proper function of the engine.

In summary, the Mercury 3973457 flywheel is an essential upgrade for your Mercury 7.4 454 Magnum marine engine. Its heavy-duty steel construction, precise balancing, and direct fit make it a reliable and efficient component for your marine powertrain system. Trust Mercury Marine for high-quality, performance-enhancing parts that will keep your engine running at its best.

Pros and Cons of Buying a Mercury 3973457 Mercruiser 7.4 454 Magnum Marine Engine

a. Power: The Mercury 3973457 Mercruiser 7.4 454 Magnum marine engine delivers impressive power, making it suitable for high-performance applications like water sports, commercial use, or large boats.

b. Durability: This engine is known for its robust construction and long-lasting components. It can withstand harsh marine environments and heavy usage.

c. Reliability: With proper maintenance, the Mercury 3973457 engine can provide years of reliable operation. It also comes with a warranty for added peace of mind.

d. versatility: This engine can be used in both inboard and outboard installations, providing flexibility for various boat configurations.

a. Size and Weight: Compared to smaller engines, the Mercury 3973457 marine engine is larger and heavier, which can make it more challenging to install and transport.

b. Fuel Consumption: Due to its high power output, this engine consumes more fuel than smaller engines, which can result in higher operating costs.

c. Complexity: The Mercury 3973457 engine is more complex than smaller engines, which can make repairs and maintenance more time-consuming and costly.

d. Cost: This engine is more expensive than smaller marine engines due to its increased power output, size, and complexity.

The Mercury 3973457 Mercruiser 7.4 454 Magnum marine engine offers impressive power, durability, and reliability that can cater to high-performance applications and large boats. However, it comes with some drawbacks, such as its size and weight, higher fuel consumption, complexity, and cost. Ultimately, the decision to buy this engine depends on your specific boating needs, budget, and technical expertise.

If you require high power output for water sports, commercial use, or a large boat, the Mercury 3973457 marine engine could be a suitable choice. Ensure you have the necessary resources, including a large boat or a well-equipped shop, to handle the engine's size, weight, and complexity. Additionally, consider the increased fuel consumption and maintenance costs in your budget planning.

Details:

Part was removed from a 1989 MerCruiser 7.4 L 454 Magnum Marine engine. Shelf 29-10-1-A. Condition: Good used condition. Mounting hardware is only included if it shown in the pictures.

Please look at all pictures and read entire before buying. Thanks -Mike. Look at pictures closely and ask any questions, I try to describe parts as best can. What you see in the pictures is what get.

I will do my best to resolve the issue.

part #: 3973457 prices

• $170.00-$200.00

specifications otsterndriv:

• for models: Marine, 454, Mercruiser, Magnum
• for makes: Mercury
• mpn: 3973457
• part type: Engine Flywheel Wheel
• country/region of manufacture: United States

payments otsterndriv:

• wallet: Paypal
• credit card: Discover
• other

general otsterndriv:

• condition: Used
• Boat Parts > Sterndrive Motors Components > Other

returns otsterndriv:

• policy: Returns Accepted
• time: 30 Days
• paid by: Buyer

shipping otsterndriv:

• type: Calculated
• carrier: FedEx, UPS, USPS
• cost: $34.11
• transit: 3-7 Days
• class: Standard, Expedited
• service: FedEx Ground or FedEx Home Delivery, UPS Ground, USPS Ground Advantage, FedEx 2Day

offer otsterndriv:

• availability: In Stock
• options: Ship-to-home
• sold: 0
• quantity: 1
• started: July 14, 2025

seller otsterndriv:

• # reviews: 105901
• rating: 99.2%
• city: Huron, Ohio

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