Sierra Marine Water Pump Impeller MPN Chart

A marine-engine cooling-water impeller must match its actual pump housing, not just the engine brand. Sierra supplies different replacement impellers with distinct manufacturer numbers. This guide lets you compare eight Sierra impeller MPNs against the pump and impeller kit references shown in their UsedRVParts catalog records, then confirm the exact application before ordering.

Start with the original pump and impeller number

1. Locate the engine detailsFind the manufacturer, engine model and serial number. Similar outboards and sterndrives may use different water pumps across production years.

2. Identify the pump kitRecord the existing pump or impeller-kit number and compare it with the catalog references below. These are part-reference clues, not an engine fitment list.

3. Confirm the impeller itselfCheck the original hub/key or drive design, diameter, height and vane count against an exact manufacturer replacement drawing or service parts list.

Sierra impellers and their catalogued pump-kit references

These kit numbers come from the corresponding Sierra product descriptions in the store. They help identify which part family to research, but do not independently confirm that an impeller is suitable for an engine or a modified pump. The complete Sierra part number and current manufacturer application lookup remain essential.

Sierra impeller MPN	Listed pump / impeller kit numbers	Reference type
18-3001	18-3201, 18-3202	Pump/impeller kit references in catalog
18-3023	18-3253, 18-3257, 18-3258	Water-pump kit references in catalog
18-3035	18-3264, 18-3267	Water-pump kit references in catalog
18-3051	18-3491, 18-3401, 18-3383, 18-3382, 18-3381, 18-3238	Water-pump kit references in catalog
18-3052	18-3252 (impeller kit); 18-3448 (water-pump kit)	Separate impeller-kit and pump-kit numbers
18-3055	18-3378, 18-3380	Water-pump kit references in catalog
18-3056	18-3214 (impeller kit); 18-3147, 18-3187, 18-3265, 18-3406, 18-3407, 18-3570 (water-pump kits)	Separate impeller-kit and pump-kit numbers
18-3060	18-3046D, 18-3046	Impeller kit references in catalog

No dimensions have been inferred. This chart intentionally does not copy impeller diameter, blade count, drive key or hub construction from similar-looking products. Before a marine-engine repair, those details must be established for the exact MPN and installed water-pump assembly.

Fit and service checks before ordering

Confirm the original engine and pump: Check the full model, serial range and current OEM service parts list. Do not assume that two engines of the same horsepower use the same pump.
Match the full Sierra number: For example, 18-3051 and 18-3052 are separate part numbers with different associated kit references.
Check the drive hub and shaft: Splines, keys and bore styles must suit the original pump. A matching outside diameter alone is insufficient.
Check pump housing condition: Inspect the wear plate, cup/liner, gaskets and seals. A damaged housing can make a new impeller ineffective.
Follow the engine manufacturer's service procedure: Use specified torque, gasket orientation and water-pump assembly instructions. Avoid running a raw-water pump without its required water supply.

Frequently asked questions

Are Sierra 18-3001 and 18-3023 interchangeable? No interchange has been established. Their catalog records reference different pump/impeller kits, and the original pump must be confirmed.

Does the impeller card include a complete water-pump kit? No. Each product in this chart is listed as a single replacement impeller, not a complete housing, gasket and wear-plate service kit.

Can I identify the impeller by vane count alone? No. Hub design, thickness, diameter, drive type and manufacturer part number are also important.

What do the kit references prove? They identify associations supplied in the store's catalog descriptions. They are a starting point for comparison, not a guarantee of engine fitment.

Browse exact Sierra Marine impeller listings

Each card links to the relevant UsedRVParts listing. Check its current condition, inventory and included parts before buying; catalog images identify the product type rather than the physical condition of an individual item.