Water Pump Repair Kit – Fits Mercury/Mariner Outboards & MerCruiser Alpha One (Replaces 46-96148Q8, 46-96148A8, 46-96148T8)

$48.50

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Water Pump Repair Kit – Fits Mercury/Mariner Outboards & MerCruiser Alpha One (Replaces 46-96148Q8, 46-96148A8, 46-96148T8) is backordered and will ship as soon as it is back in stock.

Worry-free returns

You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).

If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.

Delivery and Shipping

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This comprehensive Water Pump Repair Kit is a direct-fit replacement for a wide range of Mercury and Mariner outboards, from 65 HP 4-cylinder models up to V-6 engines using short-vane impellers. It is also designed for MerCruiser I, R, MR, and Alpha One stern drives with serial numbers from 2491586 to 0D469858.

This kit provides a direct interchange for Mercury part numbers 46-96148A8, 46-96148Q8, 46-96148T8, as well as Sierra 18-3217, 18-3316, 18-3517, and EMP 46-00090.

Engineered as a direct replacement for listed models, ensuring proper fit and function.
Includes all necessary components for a complete upper housing repair.
Features a durable plastic upper housing designed for longevity.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand	Part Number
Mercury	46-96148A8
Mercury	46-96148Q8
Mercury	46-96148T8
Sierra	18-3217
Sierra	18-3517
Sierra	18-3316
EMP	46-00090
EMP	46-00091

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury and Mariner outboards, this kit fits various 4-cylinder, 6-cylinder, and V-6 models. Check your specific HP and model notes to confirm.

Brand	Model	Rated HP	Stroke	OEM Part No.	Notes
Mercury	65	65 HP	2-Stroke	46-96148A8	4-cylinder with aluminum water pump
Mercury	65	65 HP	2-Stroke	46-96148A8	4-cylinder with plastic water pump
Mercury	70	70 HP	2-Stroke	46-96148A8	6-cylinder models
Mercury	75	75 HP	2-Stroke	46-96148A8	4-cylinder models
Mercury	80	80 HP	2-Stroke	46-96148A8	4-cylinder & 6-cylinder models
Mercury	85	85 HP	2-Stroke	46-96148A8	4-cylinder models, including 850 XS
Mercury	90	90 HP	2-Stroke	46-96148A8	6-cylinder models, including 900
Mercury	95	95 HP	2-Stroke	46-96148A8	6-cylinder models, including 950
Mercury	100	100 HP	2-Stroke	46-96148A8	6-cylinder models, including 1000
Mercury	115	115 HP	2-Stroke	46-96148A8	6-cylinder models
Mercury	125	125 HP	2-Stroke	46-96148A8	6-cylinder models
Mercury	135	135 HP	2-Stroke	46-96148A8	V-6 models
Mercury	140	140 HP	2-Stroke	46-96148A8	V-6 models, including 140 Jet
Mercury	150	150 HP	2-Stroke	46-96148A8	V-6 models, including V-150 Carb, EFI, DFI
Mercury	175	175 HP	2-Stroke	46-96148A8	V-6 models
Mercury	200	200 HP	2-Stroke	46-96148A8	V-6 models, 2.5L Carb & EFI
Mercury	220	220 HP	2-Stroke	46-96148A8	V-6 Laser models
Mariner	V-135 to V-200	135-200 HP	2-Stroke	46-96148A8	Various V-6 models

For MerCruiser stern drives, this kit fits I, R, MR, and Alpha One models, but you must verify your drive's serial number is within the specified range.

Brand	Model	OEM Part No.	Notes
MerCruiser	I	46-96148A8	Serial numbers 2491586-0D469858
MerCruiser	R	46-96148A8	Serial numbers 2491586-0D469858
MerCruiser	MR	46-96148A8	Serial numbers 2491586-0D469858
MerCruiser	Alpha One	46-96148A8	Serial numbers 2491586-0D469858

Technical Specs

Product Type: Water Pump Repair Kit
Installation: Direct replacement
Housing Material: Plastic (upper housing)
Housing Color: Black
Warranty: Manufacturer's standard warranty
Other Technical Attributes: Includes components for upper housing repair - does not include water pump base

What’s in the Box

1 x Water Pump Impeller (47-89984T-3)
1 x Plastic Pump Housing Assembly
1 x Face Plate
1 x Gaskets (Set)
1 x Drive Key
1 x Face Seal
1 x Seal Carrier
1 x Water Tube Coupling
1 x O-rings (Set)
1 x Gear Lube Fill & Vent Screw Seals

Installation Notes

Disconnect the battery and ensure the engine is off.
Place a suitable container under the lower unit and drain the gearcase lubricant.
Remove the bolts securing the lower unit (gearcase) to the drive shaft housing and carefully detach it.
Unbolt and remove the old water pump housing, impeller, and gaskets. Note the orientation of the old parts.
Thoroughly clean all mating surfaces, removing any old gasket material or debris.
Install the new components from the kit in the reverse order of disassembly. Ensure the impeller vanes are oriented correctly.
Lightly grease the new bolts and re-fasten the housing to the specified torque.
Reinstall the lower unit, ensuring the driveshaft, shift shaft, and water tube are properly aligned.
Refill the gearcase with fresh, marine-grade lubricant according to your engine's specifications.
Test the cooling system by running the engine with a proper water supply (flushing muffs or in the water), and check for a strong tell-tale stream.

Troubleshooting & FAQ

How do I confirm this kit fits my specific engine?

This kit fits a specific range of Mercury, Mariner, and MerCruiser models. For MerCruiser drives, you must verify your serial number falls between 2491586 and 0D469858. For outboards, refer to the compatibility table and match your model, HP, and any notes regarding cylinder count. Always compare the parts in the product photos to your existing parts before ordering.

What are symptoms of a worn-out water pump impeller?

Common signs include the engine overheating at idle or low speeds, a weak or non-existent "tell-tale" water stream, or a high engine temperature alarm. Visually, a worn impeller may have cracked, broken, or stiffened vanes.

How often should the water pump assembly be serviced?

As a general preventative maintenance rule, it's recommended to inspect the impeller annually and replace the entire water pump kit every 2-3 years or 200-300 hours of operation, depending on usage conditions (e.g., saltwater vs. freshwater).

Does this kit include the lower water pump base or just the upper housing?

This is an upper repair kit. It includes the plastic upper housing, impeller, face plate, and related seals and gaskets. It does not include the lower water pump base.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost?

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns?

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
This is an aftermarket replacement, not an OEM component.
Professional installation is recommended for safety and performance.

About Sea Sierra

Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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