Water Pump Impeller Kit – Fits Mercury/Mariner 200-250 HP (Replaces 817275A5)

Water Pump Impeller Kit – Fits Mercury/Mariner 200-250 HP (Replaces 817275A5)Water Pump Impeller Kit Fits Mercury Mariner 200 250 HP (Replaces 817275A5) This water pump impeller rebuild kit is designed for Mercury Mariner 200 250 HP EFI, DFI, Carb, Pro XS, and 4 Stroke outboard engines. It provides all necessary components for a complete overhaul of the lower unit water pump assembly. This kit serves as a direct replacement for multiple OEM and aftermarket part numbers, ensuring broad compatibility for various 3. 0L engine

Water Pump Impeller Kit – Fits Mercury/Mariner 200-250 HP (Replaces 817275A5)

This water pump impeller rebuild kit is designed for Mercury/Mariner 200-250 HP EFI, DFI, Carb, Pro XS, and 4-Stroke outboard engines. It provides all necessary components for a complete overhaul of the lower unit water pump assembly.

This kit serves as a direct replacement for multiple OEM and aftermarket part numbers, ensuring broad compatibility for various 3.0L engine models.

• Installation Method: Direct OEM-style replacement.
• Primary Components: Includes impeller, housing, gaskets, and seals for a full service.
• Application: Specifically designed for the lower unit water pump assembly.

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Compatible Engine Models

Confirm your engine model/year in the table below. For Mercury owners, here’s a guide to help you identify your engine’s serial/model: Mercury Serial Number Guide. You can also review exploded diagrams to verify part numbers: Mercury Parts Diagrams & Catalog.

Technical Specifications

Package Contents

• 1 x Water Pump Rebuild Kit (Replaces 817275A5)
• 1 x Seal Kit-OBM (Replaces 816575A2)
• 1 x Upper Water Pump Gasket (Replaces 8172771)
• 1 x Aluminum Cover Gasket (Replaces 430331)

Installation Guide

1. Safety First: Disconnect the battery and ensure the outboard is in the neutral position.
2. Lower Unit Removal: Remove the bolts securing the lower unit (gearcase) to the engine's upper casing.
3. Detach Gearcase: Carefully lower and separate the gearcase from the upper unit. Be mindful of the shift shaft, which may need to be disconnected.
4. Access Water Pump: Locate the water pump housing on top of the gearcase. Remove the mounting bolts to lift it off the driveshaft.
5. Disassemble Old Pump: Take off the old housing. Remove the impeller, woodruff key, wear plate, and old gaskets. Note the rotational direction of the old impeller's vanes.
6. Clean Surfaces: Thoroughly clean all mating surfaces, removing any old gasket material or sealant residue.
7. Install New Components: Place the new gaskets and wear plate onto the gearcase. Install the new woodruff key into the driveshaft.
8. Install New Impeller: Slide the new impeller onto the driveshaft, turning the shaft clockwise to help bend the vanes into the correct orientation.
9. Install New Housing: Lightly lubricate the interior of the new pump housing with marine grease or soapy water, then press it down over the impeller with a slight twisting motion.
10. Secure Housing: Align the bolt holes and tighten the housing bolts to the manufacturer-specified torque.
11. Reassemble: Reattach the gearcase to the upper unit, making sure the driveshaft, shift shaft, and water tube are properly aligned.
12. Final Test: Once fully assembled, start the engine using a flush-out device ("earmuffs") or in the water to confirm water is pumping correctly from the tell-tale outlet.

Troubleshooting & FAQ

Q: How do I confirm this kit fits my engine?
A: The most reliable method is to match your engine's model and serial number against the compatibility chart. Additionally, cross-reference your existing part number with the numbers listed in our cross-reference table. If you are unsure, please contact us with your engine details before purchasing.

Q: What are the signs of a failing water pump impeller?
A: Common symptoms include a weak or non-existent water stream from the "tell-tale" outlet, engine overheating alarms, and reduced engine performance. A visual inspection may reveal cracked, brittle, or broken vanes on the old impeller.

Q: How often should the water pump impeller be replaced?
A: For preventative maintenance, it is recommended to inspect and/or replace the water pump impeller every 100 operating hours or at least once a year, whichever comes first. This is especially important for boats used in saltwater or sandy/silty conditions.

Q: OEM vs. Aftermarket?
A: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

Q: How fast do you ship and how much does it cost?
A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

Q: What is your warranty and return policy?
A: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.