Flexible Rubber Water Pump Impeller 4528-0001 – 6 Blade Neoprene Pin Drive – Fits Yanmar 2GM 3GM, Volvo MD2020

How to Match This Part

This is a flexible rubber raw water pump impeller for marine engine and generator sea water cooling pumps. It sits inside the pump housing behind the cover plate and is driven by a pin through a slotted shaft, circulating raw water through the cooling circuit. It replaces the primary original part number Jabsco 4528-0001, and is also supplied against Johnson 09-806B / 09-806B-1, JMP 7001-01, DJ Pump 08-41-0601, Yanmar 104211-42070 / 104211-42071, Cummins Onan 132-0859, Perkins 24880272 / 24990272, Sherwood 9979 and Volvo Penta 803729 / 875807-0 / 876554-7.

Match this part by checking your engine in this order:
1. Original impeller part number (stamped on the old impeller box, or listed in the pump section of your engine parts catalog)
2. Raw water pump model (cast or labelled on the pump body, for example Jabsco 2760-0001 / 4530-0001 or Johnson F35B)
3. Engine or generator model code (on the engine identification plate)

Identify it physically before ordering. This impeller has six straight vanes moulded in black neoprene rubber around a machined brass insert, and the bore uses a slotted-shaft pin drive (through-hole) rather than a D-slot or splined hub. JMP lists the size as 39.7 mm diameter, 19.2 mm width and 9.5 mm shaft bore; DJ Pump and Jabsco catalogues round the same envelope to 40 mm × 19 mm with a 3/8 in. (9.5–10 mm) shaft. If your original impeller has a 12 mm / 15/32 in. shaft (Jabsco 22405-0001), a D-slot bore (JMP 7013-01), or a nitrile / bilge compound (4528-0003 / JMP 7001-02), it is a different part.

• ✓ Primary OEM: Jabsco 4528-0001
• ✓ Product form: 6-blade neoprene impeller, brass insert, pin drive
• ✓ Fitment: part number, then pump model, then engine model code

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands. Jabsco 4528-0001-P is the genuine retail kit packaging of 4528-0001 (impeller plus gasket and lubricant). This listing is the impeller only.

Compatible Engine Models

Confirm your engine model and the original impeller number in the table below. Serial and model information is shown on the engine identification plate, and the raw water pump model is marked on the pump body itself. Always match the original part number and the physical shape (six blades, pin drive, 3/8 in. shaft) to the product images before ordering.

Technical Specifications

Package Contents

This listing is for the impeller only, as shown in the product images. Please refer to the part number cross-reference table to confirm component details.

Cover plate gaskets, O-rings and lubricant are not included. Genuine Jabsco 4528-0001-P, JMP 7001-01K and Sherwood 9979K kits add those service parts. If your service procedure calls for a new cover seal, order it separately against your pump model.

Installation Guide

1. 1 Stop the engine or generator, let it cool, and close the raw water seacock so water cannot enter the boat while the pump is open.
2. 2 Remove the cover plate screws from the sea water pump and lift off the cover. Keep the screws and the old gasket together so you can compare the seal size when reassembling.
3. 3 Note the drive pin orientation, then grip the brass insert of the old impeller with an impeller puller or two flat-blade screwdrivers and pull it straight off the shaft. Recover any broken vane pieces from the heat exchanger inlet before continuing.
4. 4 Clean the housing bore and the wear plate, and inspect them for scoring. Apply a marine-grade impeller lubricant, glycerine or soapy water to the bore and the new vanes. Do not use petroleum-based grease, which attacks neoprene.
5. 5 Align the slot in the brass insert with the drive pin on the pump shaft, then press the impeller in while turning the shaft in the normal direction of rotation so all six vanes lay over the same way.
6. 6 Refit the cover plate with a serviceable gasket, tighten the screws evenly in a crisscross pattern, open the seacock, then start the engine and confirm steady water discharge and no leaks at the cover.

Note: Professional installation is recommended to ensure safety and optimal performance.

Troubleshooting & FAQ

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.
• The impeller is supplied on its own. Cover plate seals, gaskets and lubricant must be ordered separately if your service procedure requires them.
• Do not confuse this 9.5 mm pin-drive impeller with Jabsco 22405-0001 (15/32 in. / 12 mm shaft) or JMP 7013-01 (D-slot, 12 mm shaft).
• Never run the pump dry. Even a few seconds without water will damage the neoprene vanes.
• 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.
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