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Water Pump Impeller Kit – Fits Mercury Marine & MerCruiser 65-225HP (Replaces 46-96148A8, 46-96148Q8)

Regular price $28.00

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Product Details

This aftermarket Water Pump Impeller Kit – Fits Mercury Marine & MerCruiser 65-225HP (Replaces 46-96148A8, 46-96148Q8) is a complete assembly for servicing the cooling systems on Mercury Marine 65–225HP 2-Stroke outboards (1970–1990) and MerCruiser Alpha One, I, R, and MR sterndrives (S/N 2495186–0D469858).

It serves as a direct replacement, providing interchange for Mercury parts 46-96148A8, 46-96148Q8, 46-96148T8, and aftermarket equivalents like Sierra 18-3517 and GLM 12280.

  • Direct replacement installation with no modifications required.
  • Kit includes a durable Nylon PA66 housing and a neoprene rubber impeller.
  • Features a short-vane impeller design as required for the specified models.

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
Quicksilver 96148A8
Sierra 18-3517
GLM 12280

Engine & Model Compatibility

Confirm your engine model and serial number in the tables below.

For Mercury outboards, verify that your engine's serial number falls within the specified range for your model.

Brand Model Rated HP Stroke Serial # OEM Part No. Notes
Mercury 4-cylinder 65 2-Stroke 1542745-3293183 46-96148A8
Mercury 4-cylinder 70 2-Stroke 1503959-1566239 46-96148A8
Mercury 4-cylinder 75 2-Stroke 6432901 & Up 46-96148A8
Mercury 4-cylinder 80 2-Stroke 2559001-6432900 46-96148A8
Mercury 4-cylinder 85 2-Stroke 1566240-4861998 46-96148A8
Mercury 4-cylinder 90 2-Stroke 1766824 & Up 46-96148A8
Mercury SS 100 2-Stroke 1503332-2836018 46-96148A8
Mercury 6-cylinder 110 2-Stroke 1870204-2314955 46-96148A8
Mercury 6-cylinder 115 2-Stroke 2836019 & Up 46-96148A8
Mercury 6-cylinder 125 2-Stroke 2314956-2839368 46-96148A8
Mercury 6-cylinder 135 2-Stroke 2839369-3293233 46-96148A8
Mercury 6-cylinder 140 2-Stroke 3293234 & Up 46-96148A8
Mercury 6-cylinder 150 2-Stroke 3502806 & Up 46-96148A8
Mercury 6-cylinder 175 2-Stroke 4301235 & Up 46-96148A8
Mercury 6-cylinder 200 2-Stroke 4839034 & Up 46-96148A8 Not including V-200 DFI 3.0L
Mercury 6-cylinder 220 2-Stroke OB117316 & Up 46-96148A8

For MerCruiser sterndrives, this kit fits Pre-Alpha, Alpha One, I, R, and MR models within the specified serial number range.

Brand Model Years OEM Part No. Notes
MerCruiser Pre-Alpha 1970–1983 46-96148A8
MerCruiser Alpha One 1983–1990 46-96148A8 Fits S/N 2495186–0D469858
MerCruiser I/R/MR 1983–1990 46-96148A8 Fits S/N 2495186–0D469858

Technical Specs

Product Type
Water Pump Impeller Kit
Installation
Direct replacement
Housing Material
Nylon PA66 Plastic Water Pump Housing
Impeller Material
Neoprene Rubber
Housing Color
Black
Other Technical Attributes
Short-vane impeller design
Dimensions
150mm × 104mm × 81mm (5.91" × 4.09" × 3.19")
Weight
330g (11.6oz)
Country of Origin
Taiwan
Warranty
1 Year

What’s in the Box

  • 1 x Water Pump Housing (Replaces 46-48743A1, 46-96148, 46-96148A1)
  • 1 x Impeller (Replaces 47-30221, 47-65960, 47-85460)
  • 1 x Cup
  • 1 x Impeller Plate (Replaces 30605)
  • 1 x Water Tube Guide (Replaces 23-29804, 23-29804T)
  • 1 x Seal Ring Gasket (Replaces 26-45577, 26-455771)
  • 2 x Water Pump Housing Bushing (Replaces 26-29677)
  • 1 x Slinger Rubber Ring (Replaces 25-30271)
  • 5 x O-Ring (Replaces 25-30271, 25-896523, 25-27018)
  • 5 x Water Pump Gasket (Replaces 27-32438, 27-30603, 27-30604)
  • 2 x Drain Screw Gasket (Replaces 191833)

Installation Notes

  1. Disconnect the battery and remove the engine cover.
  2. Shift the engine into forward gear to simplify driveshaft re-engagement.
  3. Remove the bolts securing the lower unit (gearcase) to the engine leg and carefully lower it.
  4. Unbolt and remove the old water pump housing assembly from the driveshaft. Note the orientation of all parts.
  5. Thoroughly clean the mating surfaces on the gearcase and driveshaft.
  6. Assemble the new kit, starting with the base gaskets and impeller wear plate.
  7. Slide the new impeller onto the driveshaft, rotating the shaft clockwise to bend the vanes correctly.
  8. Install the new housing, seals, and remaining components from the kit.
  9. Torque the housing bolts to the manufacturer's specified value.
  10. Apply marine grease to the driveshaft splines and carefully reinstall the lower unit, ensuring the water tube and shift shaft align.
  11. Once secured, reconnect the battery and test the engine in water, confirming a steady tell-tale stream.

Troubleshooting & FAQ

How do I confirm this fits my MerCruiser Alpha One?

This kit is specifically for Alpha One sterndrives with serial numbers from 2495186 to 0D469858. Models outside this range, including Alpha One Gen II drives, require a different kit.

What are the symptoms of a failing impeller?

Common signs include the engine temperature rising above normal at idle or low speeds, a weak or non-existent water stream from the "tell-tale" outlet, and in severe cases, a steam cloud from the exhaust.

How often should this water pump kit be replaced?

For preventative maintenance, it is recommended to replace the impeller and associated components every 1–2 years or every 100–200 hours of operation, whichever comes first. This is especially critical for boats used in saltwater.

What is a "short-vane" impeller and why is it important?

This kit uses a short-vane impeller, which was the original design for the specified 1970–1990 Mercury engines. Using an incorrect (e.g., long-vane) impeller can result in improper housing fit, reduced water pressure, and engine overheating.

My engine overheated. Is replacing the impeller kit enough?

If your engine has severely overheated, the impeller may have disintegrated. Replacing the kit is the first step, but you must also inspect and clear the engine's cooling passages of any old impeller fragments to prevent blockages.

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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