Why pay dealer markup? Get genuine Mercury Marine quality at discount pricing. This **HOSE ASSEMBLY, Circulation Pump to Thermostat Housing** delivers OEM reliability with savings up to 20% below retail.

Factory-built to exact Mercury Marine specifications, this water pump assembly ensures reliable operation across all engine RPM ranges. Part number 861590A05 is manufactured to exact Mercury Marine factory specifications for precision installation and optimal performance. Constructed from premium marine-grade materials designed to withstand harsh saltwater and freshwater environments.

Factory parts exist for a reason – they work. Part 861590A05 undergoes rigorous Mercury Marine quality testing that aftermarket manufacturers skip. The result? Reliable performance season after season.

FITS: 4-383HP MERCRUISER, RACE STERNDRIVE

• Fits MERCRUISER, RACE STERNDRIVE 4-383HP engines
• Compatible HP: 4HP, 5HP, 357HP, 383HP
• Covers 24 serial number ranges
• Configurations: Outboard, Sterndrive
• OEM genuine Mercury Marine part

COMPLETE SERIAL NUMBER COMPATIBILITY:

4HP Models

• 4HP OUTBOARD (Mercruiser): 0M615000-0W300012, 0W300013-0W309999, 0W310000-0W649999, 0W650000-1A063239

5HP Models

• 5HP OUTBOARD (Mercruiser): 0M317000-0W090899, 0W090900-0W689999

357HP Models

• 357HP OUTBOARD (Mercruiser)

383HP Models

• 383HP OUTBOARD (Mercruiser)
• 383HP STROKER (Mercruiser)

HP Models

• HP OUTBOARD (Mercruiser): 0M391600-0W689999, 0W690000-0W698432, 0K040001-0M391599, 0M391750-0W689999, 0W690000-0W698432, 0L670015-0M391599, 0L680003-0M299999
• HP STERNDRIVE (Race Sterndrive): 0K000656-0L600314

Looking for your engine serial number? Our helpful guide shows you exactly where Mercury places serial numbers on different models.

Double-check compatibility for part 861590A05 using our parts finder tool. Still need assistance? No worries – contact us via the buttons at the bottom of this page (text, call, or email).

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