Water Pump Impeller Rebuild Kit with Housing for Mercury/Mariner Outboards – Replaces 817275A5
Water Pump Impeller Rebuild Kit with Housing for Mercury/Mariner Outboards – Replaces 817275A5 is backordered and will ship as soon as it is back in stock.
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Water Pump Impeller Rebuild Kit with Housing for Mercury/Mariner Ou...
Water Pump Impeller Rebuild Kit with Housing for Mercury/Mariner Outboards – Replaces 817275A5 is backordered and will ship as soon as it is back in stock.
Product Details
This is a complete water pump impeller rebuild kit with housing for selected Mercury and Mariner outboard applications. It is intended to service the lower-unit water pump and help restore the cooling-water flow required for normal engine operation.
The kit is listed as a replacement for Mercury part numbers 817275A5, 817275Q05, 817275A6, and 847275A5. It is also cross-referenced with Sierra 18-3147, GLM 12098, and EMP 46-46502. Confirm the part number, engine model, year, serial-number range, and stroke before ordering.
- Water pump impeller rebuild kit with housing.
- For servicing the lower-unit water pump assembly.
- Designed to help restore cooling-water circulation and reduce the risk of overheating caused by a worn pump component.
- Aftermarket replacement; not a genuine Mercury component.
Part Number Matrix
Use these references as identification aids only. Verify the complete engine application before installation.
| Brand | Part Number |
|---|---|
| Mercury | 817275A5 |
| Mercury | 817275Q05 |
| Mercury | 817275A6 |
| Mercury | 847275A5 |
| Sierra | 18-3147 |
| GLM | 12098 |
| EMP | 46-46502 |
Engine & Model Compatibility
This kit is associated with selected Mercury and Mariner outboards in the 200–250 HP application range, including certain 200 DFI, 200 EFI, 225 Carb, 225 DFI, 225 EFI, 225 Pro XS, 250, and 3.0L EFI/DFI configurations. The exact application can vary by model designation, year, serial-number range, gearcase, and stroke.
Important: DFI, EFI, Carb, and Pro XS designations do not by themselves confirm the stroke or fitment. Confirm that your original water-pump part number matches one of the references above and verify the complete engine model and serial number before purchase. Do not rely on horsepower alone.
Technical Specs
- Product Type
- Water pump impeller rebuild kit with housing
- Application
- Selected Mercury and Mariner outboard lower-unit water pumps
- Installation
- Replacement service part; installation requires removal of the lower unit
- Product Status
- Aftermarket replacement, not OEM
What’s in the Box
- 1 x Water pump rebuild kit with housing
- 1 x Seal kit-OBM, reference 816575A2
- 1 x Upper water pump gasket, reference 8172771
- 1 x Aluminum cover gasket, reference 430331
Package contents are intended for the rebuild configuration described above. Compare the supplied components with the original assembly before installation and confirm that all required fasteners and service parts are present.
Installation Notes
- Disconnect the battery and make sure the engine is switched off and secured.
- Drain the gearcase lubricant from the lower unit according to the engine service procedure.
- Remove the lower unit from the outboard by removing the retaining hardware and separating it from the midsection.
- Place the lower unit on a suitable workbench and remove the old water-pump housing.
- Remove the old impeller, key, gaskets, seals, and related pump components. Clean all mating surfaces carefully.
- Install the replacement gaskets, seals, wear plate, and impeller key included or specified for the pump assembly.
- Fit the new impeller to the driveshaft, making sure the key is correctly aligned.
- Lubricate the inside of the housing with a suitable assembly lubricant and install the housing over the impeller while turning the driveshaft in the correct direction for the engine.
- Secure the housing and related components using the engine manufacturer’s specified sequence and torque values.
- Reinstall the lower unit, refill the gearcase with the correct lubricant, and reconnect the battery.
- Run a cooling-system test with an appropriate flush attachment before returning the boat to service. Stop immediately if the engine overheats or the tell-tale flow is abnormal.
Consult the applicable Mercury or Mariner service manual for model-specific removal procedures, impeller-vane direction, torque specifications, lubricant requirements, and safety precautions.
Troubleshooting & FAQ
How do I know if my water pump impeller is failing?
Common signs include weak or absent water flow from the tell-tale outlet, an overheating warning, unusually high operating temperature, or reduced engine performance. Inspect the pump when these symptoms occur and replace damaged or aged components.
When should the water pump impeller be replaced?
Replacement intervals depend on the engine manufacturer’s service schedule, operating hours, storage conditions, and exposure to salt, sand, or debris. Follow the service manual for your exact engine and inspect the impeller whenever cooling performance is reduced.
Will this kit fit every Mercury or Mariner 200–250 HP engine?
No. Horsepower alone does not confirm fitment. Model designation, year, serial-number range, gearcase configuration, stroke, and the original water-pump part number must be checked before ordering.
Is this an OEM Mercury part?
No. This is an aftermarket replacement kit that is cross-referenced to the part numbers shown on this page. It is not manufactured or branded by Mercury.
Can I install this kit myself?
Installation requires lower-unit removal and careful water-pump assembly work. Use the correct service manual and torque specifications for your engine. Professional installation is recommended if you are not familiar with outboard gearcase service.
What should I check before ordering?
Compare your original part number and pump components with the references and package list above. Also verify the exact engine brand, model, year, serial-number range, stroke, and gearcase application.
Safety & Important Info
- Verify the original part number and complete engine application before purchase.
- Do not use horsepower alone to determine compatibility.
- Disconnect the battery and follow the applicable service-manual procedures during installation.
- Use the manufacturer’s specified torque values, lubricants, and installation direction.
- This is an aftermarket replacement kit, not an OEM component.
- Professional installation is recommended for safe and reliable operation.
About Sea Sierra
- Marine Replacement Parts — We supply aftermarket components for routine marine maintenance and repair.
- Application-Focused Ordering — Compare part numbers and complete engine details before placing an order.
- Practical Service Support — Follow the applicable engine service information for installation and maintenance.
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