Restore factory performance to your Mercury engine with this OEM O-RING, OIL COOLER COVER COMPONENT OF ENGINE/POWERHEAD GASKET SET [27- 43186A 1]. Engineered to exact specifications for reliable operation in fresh and saltwater conditions.

Built with Mercury Marine’s precision engineering, this gasket ensures reliable operation across all engine RPM ranges. Part number 42357 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.

Aftermarket parts might save a few dollars upfront, but genuine Mercury Marine part 42357 saves you money long-term by lasting years instead of months. Factory precision means perfect fit — no modifications, no surprises.

Compatible Mercury Marine Engines

FITS: 3-488HP MERCRUISER

• Fits MERCRUISER 3-488HP engines
• Compatible HP: 3HP, 165HP, 170HP, 180HP, 190HP, 488HP
• Covers 7 serial number ranges
• Configurations: Outboard
• OEM genuine Mercury Marine part

COMPLETE SERIAL NUMBER COMPATIBILITY:

3HP Models

• 3HP OUTBOARD (Mercruiser)

165HP Models

• 165HP OUTBOARD (Mercruiser): 0B434941-0B774251

170HP Models

• 170HP OUTBOARD (Mercruiser): 6916779-0B434940

180HP Models

• 180HP OUTBOARD (Mercruiser): 0B436391-0B775248

190HP Models

• 190HP OUTBOARD (Mercruiser): 6916779-0B436390

488HP Models

• 488HP OUTBOARD (Mercruiser): 6170297-6916778

Need help finding your serial number? Check our serial number location guide for step-by-step instructions on locating it on your Mercury engine.

Verification & Support

Not sure if part 42357 fits your engine? Try our parts finder tool — it’s quick and easy. Need expert help? Contact us using the buttons at the bottom of this page – text, call, or email, whatever works best for you

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