MARINER/ YAMAHA 1651-9681M Cylinder Lower Unit Gearcase 40

( Brand: Mariner/ Yamaha ), ( Manufacturer Part Number: 1651-9681M ), ( Part Type: Hp Cylinder Unit ), ( Stroke: 2-stroke ), ( Engine Hp : 40 )

Review MARINER/ YAMAHA Stroke Cylinder 40 Hp Lower Unit Gearcase Inch Pn fits 2020

Mariner/Yamaha 1651-9681M Cylinder 40 HP Lower Unit Gearcase 20

Experience unparalleled performance and durability with the Mariner/Yamaha 1651-9681M Cylinder 40 HP Lower Unit Gearcase 20. This high-performance lower unit gearcase is designed for ultimate reliability and efficiency, making it an ideal choice for a wide range of watercraft applications.

Crafted by the renowned Yamaha Marine Group, this lower unit gearcase is engineered with precision and care, ensuring a perfect fit with the Mariner 40 HP outboard engine. The 1651-9681M features a robust and durable construction, built to withstand the rigors of continuous use in various water conditions.

The lower unit gearcase houses a high-capacity, 20-inch (508 mm) pitch propeller, designed to deliver optimal thrust and maneuverability. Its multi-stage, marine-grade gear system offers smooth, quiet operation and exceptional power transfer from the engine to the propeller.

The 1651-9681M also boasts a corrosion-resistant finish, protecting the gearcase from the harsh marine environment. This finish, combined with the unit's high-quality seals and bearings, ensures long-lasting performance and minimal maintenance.

In addition, the lower unit gearcase features a built-in trim system, allowing for easy adjustment of the outboard's tilt angle for optimal performance in different water conditions. The trim system is highly responsive and precise, ensuring a smooth and seamless boating experience.

The Mariner/Yamaha 1651-9681M Cylinder 40 HP Lower Unit Gearcase 20 is a testament to Yamaha's commitment to quality and innovation. Whether you're a seasoned boater or a newcomer to the water, this lower unit gearcase delivers the power, performance, and reliability you need to make the most of your time on the water.

**Mariner/ Yamaha 1651-9681M Cylinder 40 HP Lower Unit Gearcase 20:** A Detailed Analysis

1. **Reputation:** Mariner and Yamaha are well-known brands in the marine industry, ensuring a high-quality product.

2. **Power:** This 40 HP lower unit offers enough power for various recreational activities such as fishing and water sports.

3. **Reliability:** Known for their durability, these lower units can withstand the harsh marine environment.

4. **Versatility:** This lower unit is suitable for a wide range of boats, making it a versatile option.

5. **Service and Support:** As part of the Yamaha family, you can expect excellent customer service and support.

1. **Price:** Compared to some lower-end models, this unit may be more expensive.

2. **Weight:** At approximately 175 lbs, it might be heavier than some other models, which could affect boat maneuverability.

3. **Fuel Efficiency:** While not the least efficient, this unit may consume more fuel compared to some smaller models.

4. **Availability of Parts:** While Yamaha parts are generally easy to find, some less common parts might be harder to source.

The Mariner/ Yamaha 1651-9681M Cylinder 40 HP Lower Unit Gearcase 20 is a reliable and powerful option suitable for various recreational activities. However, its price and weight might be considerations for some buyers. If affordability and minimal weight are not major concerns, this lower unit could be an excellent choice due to its high-quality construction, brand reputation, and versatility.

If you're in the market for a powerful and durable lower unit for your boat, the Mariner/ Yamaha 1651-9681M Cylinder 40 HP Lower Unit Gearcase 20 is a strong contender. Weighing the pros and cons, if the price and weight are not significant concerns, we recommend considering this lower unit for your marine needs.

Details:

Shifts and prop shaft is straight. Holds 12 psi pressure.

part #: 16519681m prices

• $300.00-$350.00

specifications ouboaen:

• for years: 2020
• brand: Mariner/ Yamaha
• mpn: 1651-9681m
• part type: Hp Cylinder Unit
• stroke: 2-stroke
• engine hp : 40

payments ouboaen:

• wallet: Apple-pay
• credit card: Diners-club
• other

offer ouboaen:

• availability: In Stock
• started: November 15, 2025
• sold: 0
• quantity: 1
• options: Ship-to-home
• best offers: True

returns ouboaen:

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

general ouboaen:

• condition: Used
• Boat Parts > Outboard Engines Components > Complete Outboard Lower Units

seller ouboaen:

• rating: 99.3%
• # reviews: 6490
• city: Spokane, Washington

shipping ouboaen:

• class: Standard
• type: Fixed
• service: UPS Ground
• carrier: UPS
• cost: $125.00
• transit: 4-9 Days

Mariner/ Yamaha 1651-9681M Is Similar To:

• 10321 Stiletto Prop Mercury Mariner Yamaha Outboard Propeller (29.6% similar) May fit more engines. Condition: used but in good condition and guaranteed to function properly. Please see included pictures. Part: 10321 stiletto prop x 21P v6 mercury mariner Yamaha outboard propeller fits various motor parts. This propeller will also fit Yamaha outboard motors with the correct ...(January 7th, 2019)
• 134-4512-3 Cdi Electronics Mercury Mariner Chrysler Force Trigger Cylinder 736983851420 (28.6% similar) Chrysler force outboards:fits, 40, 50, 65, hp. CID electronics mercury mariner Chrysler fossicked TRIGGER3 CYLINDER134 mfr: electronics part order UPC: 20 condition: new : mercury force outboard trigger 3 cylinder. Replaces: 834520T, 854512T, 855746A1, 855746A12, mercury mariner outboards: fits, 40...(June 9th, 2018)
• 134-9021-3 Cdi Electronics Trigger Mercury Mariner Cylinder Hp (26.6% similar) This is new in box I opened it up for inspection and pictures...(September 28th, 2018)
• 1587-6842m Mariner Outboard Gearcase (34.2% similar) As such, selling parts only. Gearcase is complete with all parts however shift shaft was removed but not reinstalled. Shifted through gears but never water tested. Complete lower gearcase from early mariner 55HP outboard...(October 16th, 2018)
• 1647-9148a11 Mercury Mariner Outboard Lower Unit Gear Case Housing Hp (44% similar) The paint is pretty scratched and scuffed but there no major damage to this case. Fits some mercury mariner outboards with hp from the 80S and 90'S. The keg is in good condition. The inside is in good condition and not scratched or gouged. There are a few small dings in it but is straight and not ...(March 20th, 2018)
• 1651-8258m Mariner Yamaha 8258m Lower (39% similar) Help buy shipping-globally. Net parts detail mariner outboard M-8258M. Net link for model's this part is used on. Yamaha mariner 8258M lower unit gear housing - long 5HP condition: pressure test: zero drop no leaks vacuum pass shifting: shifts properly driveshaft splines: good prop shaft good ...(August 14th, 2017)
• 1655-7332 Mercury Mariner Outboard Gearcase Lower Unit (34.1% similar) This is off a late 70S 115HP mercury. Complete working gear case for mercury inline 6 and older 4 cylinder outboards. Comes with 24P brass propeller. No oil leaks straight keg with dents and a good water pump...(May 22nd, 2018)
• 1667-9011g90 Mercury Mariner Bigfoot Lower (24.4% similar) Impeller might need to be replaced but visually looked good. Shift thru all gears and turns smooth. The driveshaft measures from tip of to base water pump and is known as a long shaft. Brand: mercury year: horse power: 40-60 this sale is for one used mercury mariner Bigfoot outboard 20 long shaft ...(October 15th, 2017)
• 16715m Mercury Mariner Yamaha Outboard Linkage Rod Connector Joint (34% similar) Item mercury joint, part number 16715M. New old stock from dealer close out...(December 27th, 2018)
• 174-5456-16 Cdi Electronics Mercury Mariner Stator Cylinder Amp 736983852403 (31.8% similar) Mercury mariner outboards:replaces: 398-5454A11, 398-5454A15, 398-5454A16, 398-5454A30, 398-5454A31, 398-5454A32, 398-5454A34, 398-5454A35, 398-5454A36, 398-5454A55, 398-5454A61, 398-5454A64, 398-5454A66, PH400-0004, 16FITS: amp. CID electronics mercury MARINERSTATOR6 CYLINDER16 AMP1 mfr: ...(October 8th, 2018)
• 18-2626 Sierra Mercury Mariner Lower Unit Seal Kit Outboard 808282243685 (31.4% similar) Mercury mariner outboards:replaces: 26-43035A4. Sierra marine mercury mariner lower unit seal KITOUTBOARD18-2626 mfr: part order UPC: 85 condition: new : mercury mariner outboard lower unit seal kit...(June 27th, 2018)