This water pump impeller for Yamaha/Mariner outboard motors is a CEF replacement part for the engine's cooling water pump. This variant is intended for 4/5 HP Yamaha and Mariner engines in the documented 2-stroke versions, as well as the 4 HP primary 4-stroke application.
The impeller rotates in the water pump housing and creates the cooling water flow that carries cooling water through the engine's cooling system. It has six flexible blades and is manufactured from black neoprene for water applications. Worn, cracked, or hardened blades can reduce the cooling water volume and increase the risk of overheating.
The impeller has an inner diameter of 11 mm, an outer diameter of 40 mm, and a width of 12.6 mm. It is mounted directly onto the water pump drive shaft and uses a Key Drive system.
The CEF part number is 500325, also known as IMP-500325 and CEF500325. It replaces Yamaha reference 6E0-44352-00 and 6E0-44352-00-00, as well as Mercury/Mariner reference 47-96305M. Documented OEM references also include Parsun F4-03060000, Hidea 06.21.03.00, and Selva 6E0-44352-00.
Compatible engine models
Documented Yamaha compatibility includes 4A, 5C, F4A, F4B, F5A, and F6C. Historical applications include Yamaha 4 HP from 1984-1999 and Yamaha 5 HP from 1984-2002. For Mariner, the application includes 4A M from serial number 6E0-001011, 4A ML from 6E0-300101, 5C M from 6E3-102151, and 5C ML from 6E3-400101.
The impeller is also documented for Parsun 4/5 HP 4-stroke, Hidea 2.5/4/5 HP, and Selva 4 HP 4-stroke. Aftermarket cross-references include Sierra 18-3073, Mallory 9-45611, and GLM 89860.
Check the impeller blades regularly and replace the part in case of cracks, deformation, or hardening. There is no documented included gasket or specific gasket kit for this variant.
Always check the engine/drive model, year, serial number, and original part number before purchasing.
Key featuresWater pump impeller for outboard engine cooling system
For Yamaha/Mariner 4/5 HP
Compatible with documented 2- and 4-stroke engines
6 flexible blades
11 mm inner diameter
40 mm outer diameter
12.6 mm width
Black neoprene
Key Drive
Replaces, among others, OEM 6E0-44352-00 and 47-96305M
