Flexible Rubber Water Pump Impeller 18786-0001 – 9 Blade Neoprene Double-Flat – Fits JMP 9000-01

How to Match This Part

This is a flexible rubber raw water pump impeller. It sits inside the pump housing behind the cover plate and is driven by a double-flat shaft. It replaces the primary original part number Jabsco 18786-0001 (also 18786-0001B / 18786-0001-W), and is also supplied against JMP 9000-01, DJ 08-16-0901 and Caterpillar FP-7E3022.

Match this part by checking your engine in this order:
1. Original impeller part number (stamped on the old impeller or listed in the pump section of your parts catalog)
2. Blade count (this listing is 9 blades)
3. Drive type (this listing is a double-flat hub, 25 mm bore — not the 12-spline 17240-0001 / 9001-01 cousin)
4. Diameter and width (this listing is 117 mm diameter and 88.5 mm wide)

Identify it physically before ordering. This impeller has nine vanes moulded in black neoprene around a double-flat insert. JMP 9000-01 is 117 mm diameter, 88.5 mm width and 25 mm bore. Genuine Jabsco 18786-0001-W kits include an O-ring and lubricant; this listing is the impeller only.

• ✓ Primary OEM: Jabsco 18786-0001
• ✓ Product form: 9-blade neoprene impeller, double-flat insert, 117 × 88.5 × 25 mm
• ✓ Fitment: part number, then double-flat vs spline

Part Number Cross-Reference

Use this table to confirm equivalent part numbers. Some retailers list 18786-0001-W or 9000-01K as a kit. This listing is the impeller only.

Compatible Engine Models

Confirm the original impeller number and count nine blades on a double-flat hub 88.5 mm wide. Do not assume every CAT or Detroit Diesel pump uses this impeller.

Technical Specifications

Package Contents

This listing is for the impeller only. Product photos of the genuine Jabsco kit show an O-ring and lubricant; those extras are not included. Please refer to the part number cross-reference table to confirm component details.

Cover gasket, O-ring and lubricant are not included.

Installation Guide

1. 1 Stop the engine, 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 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 double-flat orientation, then grip the hub and pull the old impeller straight off. Recover any broken vane pieces from the downstream cooling circuit 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 double flats in the hub with the pump shaft, then press the impeller in while turning the shaft in the normal direction of rotation so all nine 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 a solid stream of cooling water 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 seals and lubricant must be ordered separately if your service procedure requires them.
• This is a 9-blade, 117 mm double-flat impeller, 88.5 mm wide with a 25 mm bore. It will not fit 12-spline 17240-0001 / 9001-01 of the same envelope.
• 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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