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Water Pump Upper Repair Kit – Fits Mercury/Mariner 65 HP (4-Cylinder) & V-6 Outboards, MerCruiser I/R/MR/Alpha Stern Drives (Replaces 46-96148A8)

Regular price $57.99
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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 aftermarket Water Pump Upper Repair Kit is designed for a broad range of Mercury/Mariner and MerCruiser engines. It fits Mercury/Mariner models from 65 HP (4-Cylinder) through V-6 outboards that use short-vane impellers, as well as MerCruiser I, R, MR, and Alpha Sterndrive models (serial numbers 2491586 to 0D469858).

This kit serves as a direct replacement for multiple part numbers, including Mercury Marine 46-96148A8, Quicksilver 46-96148A8, Sierra 18-3217, Mallory 9-48311, and GLM 12280, ensuring wide compatibility.

  • Installs in the upper water pump housing.
  • Features a durable plastic pump housing.
  • Engineered specifically for systems using short-vane impellers.

Part Number Matrix

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

Brand Part Number
Mercury Marine 46-96148A8
Quicksilver 46-96148A8
Sierra 18-3217
Mallory 9-48311
GLM 12280

Engine & Model Compatibility

Confirm your engine model/year in the table below.

For Mercury and Mariner outboards, check your model and serial number range to ensure a match.

Brand Model Rated HP Stroke Years OEM Part No. Notes
Mercury Outboard 65 4-Cylinder (Serial # 1542745-3293183) 46-96148A8
Mercury Outboard 70 4-Cylinder (Serial # 1503959-1566239) 46-96148A8
Mercury Outboard 75 (Serial # 6432901 & Up) 46-96148A8
Mercury Outboard 80 (Serial # 2559001-6432900) 46-96148A8
Mercury Outboard 85 (Serial # 1566240-4861998) 46-96148A8
Mercury Outboard 90 (Serial # 1766824 & Up) 46-96148A8
Mercury Outboard 100 SS (Serial # 1503332-2836018) 46-96148A8
Mercury Outboard 110 (Serial # 1870204-2314955) 46-96148A8
Mercury Outboard 115 6-Cylinder (Serial # 2836019 & Up) 46-96148A8
Mercury Outboard 125 (Serial # 2314956-2839368) 46-96148A8
Mercury Outboard 135 (Serial # 2839369-3293233) 46-96148A8
Mercury Outboard 140 (Serial # 3293234 & Up) 46-96148A8
Mercury Outboard 150 (Serial # 3502806 & Up) 46-96148A8
Mercury Outboard 175 (Serial # 4301235 & Up) 46-96148A8
Mercury Outboard 200 (Serial # 4839034 & Up, not including V-200 DFI 3.0L) 46-96148A8
Mercury Outboard 220 (Serial # OB117316 & Up) 46-96148A8
Mariner Outboard 65 4-Cylinder 46-96148A8
Mariner Outboard V-6 46-96148A8

This kit is compatible with MerCruiser sterndrives within the specified serial number range, which includes Pre-Alpha and Alpha One models.

Brand Model Years OEM Part No. Notes
MerCruiser I 1963–1990 (Serial # 2491586-0D469858) 46-96148A8 Includes Pre-Alpha and Alpha One
MerCruiser R 1963–1990 (Serial # 2491586-0D469858) 46-96148A8 Includes Pre-Alpha and Alpha One
MerCruiser MR 1963–1990 (Serial # 2491586-0D469858) 46-96148A8 Includes Pre-Alpha and Alpha One
MerCruiser Alpha 1963–1990 (Serial # 2491586-0D469858) 46-96148A8 Includes Pre-Alpha and Alpha One

Technical Specs

Product Type
Water Pump Repair Kit
Installation Location
Upper Housing
Housing Material
Plastic
Product Dimensions
16.0cm L x 12.0cm W x 12.5cm H
Weight
0.33 kg (11.6 oz)
Impeller Design
Short-vane

What’s in the Box

  • 1 x Water Impeller (47-30221/47-65960)
  • 1 x Plastic Pump Housing (46-48743A1/46-96148)
  • 1 x Face Plate (30605)
  • Gaskets (27-32438/27-30603/27-30604)
  • 1 x Drive Key
  • 1 x Face Seal
  • 1 x Seal Carrier
  • 1 x Water Tube Coupling (23-29804/23-29804T)
  • 1 x Seal Ring Gasket (26-45577/26-455771)
  • 1 x Water Pump Housing Bushing (26-29677)
  • 2 x Drain Screw Gasket (191833)
  • O-Rings (25-30271/25-896523/25-27018)
  • 1 x Slinger Rubber Ring (25-30271)
  • 1 x Cup

Installation Notes

  1. Disconnect the battery and ensure the engine is off and cool.
  2. Place a drain pan under the lower unit and remove the gear lube drain/fill screw to drain the oil.
  3. Remove the bolts securing the lower unit (gearcase) to the upper housing and carefully lower it.
  4. Unbolt and remove the old water pump housing assembly. Note the orientation of the old impeller vanes.
  5. Thoroughly clean the mounting surfaces, removing any old gasket material or sealant.
  6. Install the new gaskets, face plate, impeller (with vanes oriented correctly), and housing from the kit.
  7. Lightly grease the new components as needed before assembly.
  8. Reinstall the lower unit, ensuring the water tube and driveshaft are correctly aligned.
  9. Tighten all bolts to the manufacturer's specified torque.
  10. Refill the lower unit with fresh gear lube until it flows from the upper vent hole, then replace plugs.
  11. Reconnect the battery, start the engine using a water supply (flushing muffs), and verify water is exiting the tell-tale port.

Troubleshooting & FAQ

Does this kit include the water pump base?

No, this is an upper housing repair kit. It includes the plastic pump housing, impeller, face plate, and seals, but it does not include the lower water pump base or mounting screws.

Is the pump housing made of plastic or metal?

The housing included in this kit is made of durable, corrosion-resistant plastic, consistent with the specified OEM design.

What are the signs of a failing water pump impeller?

Common symptoms include the engine overheating at idle or low speeds, a weak or non-existent water stream from the tell-tale port, and a melted water pump housing. Failure to replace a worn impeller can lead to severe engine damage.

How often should I replace my water pump impeller?

For preventative maintenance, it is recommended to replace the impeller every 1-2 years or every 100-200 hours of operation, especially for boats used in saltwater or sandy/silty conditions.

Will this fit a MerCruiser Alpha One Gen II drive?

No. This kit is designed for MerCruiser I, R, MR, and Alpha One (Gen I) drives with serial numbers up to 0D469858. Gen II drives require a different water pump kit.

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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