Experiencing engine hesitation or reduced power? This authentic Mercury Marine O-RING KIT solves the problem with factory precision – no guessing, no compromises.

Built with Mercury Marine’s precision engineering, this seal ensures reliable operation across all engine RPM ranges. Part number 804840 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 804840 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: 2-200HP MARINER, MERCURY, RACE OUTBOARD (DFI)

• Fits MARINER, MERCURY, RACE OUTBOARD 2-200HP engines
• Compatible with 7 different HP configurations
• Model types: DFI
• Covers 24 serial number ranges
• Configurations: Jet Drive, Outboard
• OEM genuine Mercury Marine part

COMPLETE SERIAL NUMBER COMPATIBILITY:

2HP Models

• 2HP OUTBOARD (Race Outboard): 0T997974-1E000796

110HP Models

• 110HP JET (Mercury)

115HP Models

• 115HP DFI (Mariner): 0T980000-1B226999, 1B227000-1B417701, 1B417702-1B736885
• 115HP DFI (Mercury): 0T801000-1B226999, 1B227000-1B417701, 1B417702-1B736885
• 115HP OUTBOARD (Mercury)

125HP Models

• 125HP DFI (Mariner)
• 125HP DFI (Mercury)

150HP Models

• 150HP OUTBOARD (Mercury)

175HP Models

• 175HP PROXS (Mercury)

200HP Models

• 200HP OUTBOARD (Mariner): 0G960500-0T178499, 0T178500-0T598999, 0T599000-0T800999
• 200HP OUTBOARD (Mercury): 0T980000-1B417701, 1B417702-1B504988, 0G960500-0T178499, 0T178500-0T598999, 0T599000-0T800999

Looking for your Mercury engine serial number? Our helpful guide shows you exactly where serial numbers are located on different engines.

Verification & Support

Want to verify compatibility for part 804840? Use our parts finder tool for instant confirmation. Still have questions? No problem – use the contact buttons at the bottom of this page to reach us by text, call, or email

Serving boaters for over 40 years. Great prices, quick delivery – your parts ship fast.