25889316 Mercury MerCruiser O-Ring | Genuine Quicksilver OEM Part

🔧 Product Description

Genuine Quicksilver VST Boost Pump O-Ring - Part Number: 25-889316

A genuine Quicksilver O-ring used on Mercury / Mariner DFI / OptiMax VST boost pump assemblies. This O-ring seals the boost pump in the vapor separator / fuel supply module area on selected 75HP to 300HP DFI engines where the parts diagram specifies 25-889316.

⚙️ Key Features

• Genuine Quicksilver OEM O-ring

• Correct Mercury part number 25-889316

• VST boost pump O-ring application

• Used on Mercury / Mariner DFI / OptiMax fuel systems

• Fits selected 75HP to 300HP DFI engines where specified

🔄 Supersession & Cross Reference

OEM Supersession Chain:

• 25-889316 current OEM VST boost pump O-ring reference

• 25-8893161 related / alternate formatted O-ring reference

OEM / Related Numbers:

• 25-889316

• 889316

• 25889316

• 25-8893161

• 8893161

• Mercury 25-889316

• Quicksilver 25-889316

• VST boost pump O-ring

• Vapor separator pump O-ring

• DFI fuel module O-ring

Aftermarket / Verified Equivalents:

• Aftermarket VST boost pump O-ring equivalents exist where matched to 25-889316

• Final replacement should be matched by engine serial number and fuel-system diagram

🚤 Compatibility

Commonly used on:

• Mercury / Mariner DFI / OptiMax vapor separator tanks

• Mercury VST boost pump sealing locations

• Mercury fuel supply module / boost pump service where 25-889316 is specified

Typically suits:

• Engine models:

• Mercury 75 DFI 1.5L 3-cylinder - serial 0T980000 to 1B226999

• Mercury 75 DFI 1.5L 3-cylinder - serial 1B227000 to 1B417701

• Mercury 75 DFI 1.5L 3-cylinder - serial 1B417702 and up where specified

• Mercury 90 DFI 1.5L 3-cylinder - serial 0T801000 to 1B226999

• Mercury 90 DFI 1.5L 3-cylinder - serial 1B227000 to 1B417701

• Mercury 90 DFI 1.5L 3-cylinder - serial 1B417702 and up where specified

• Mercury 115 DFI 1.5L 3-cylinder - serial 0T801000 to 1B226999

• Mercury 115 DFI 1.5L 3-cylinder - serial 1B227000 to 1B417701

• Mercury 115 DFI 1.5L 3-cylinder - serial 1B417702 and up where specified

• Mercury 115 Pro XS 1.5L 3-cylinder - serial 1B751825 and up where specified

• Mercury 125 DFI 1.5L 3-cylinder - serial 1B736885 and up where specified

• Mercury 135 DFI / OptiMax 2.5L fuel-system applications where 25-889316 is specified

• Mercury 150 DFI / OptiMax 2.5L fuel-system applications where 25-889316 is specified

• Mercury 175 DFI / OptiMax 2.5L fuel-system applications where 25-889316 is specified

• Mercury 200 DFI / OptiMax 3.0L fuel-system applications where 25-889316 is specified

• Mercury 225 DFI / OptiMax 3.0L fuel-system applications where 25-889316 is specified

• Mercury 250 DFI / OptiMax 3.0L fuel-system applications where 25-889316 is specified

• Mercury 300 DFI / OptiMax 3.0L / 3.2L fuel-system applications where 25-889316 is specified

• Mariner 75HP to 300HP DFI / OptiMax applications using VST boost pump O-ring 25-889316

• HP Range: commonly 75HP - 300HP where specified

• Engine Type: Mercury / Mariner DFI / OptiMax outboard

• System Type: VST boost pump / vapor separator O-ring

🔌 Function

The O-ring seals the VST boost pump in the fuel module or vapor separator assembly, helping maintain correct fuel pressure and preventing fuel leakage around the pump body.

Common signs of failure:

• Fuel smell or seepage around VST

• Hard starting or fuel pressure loss

• Boost pump removed and O-ring disturbed

• O-ring swollen, cut or flattened

• Fuel pressure fault after VST service

• Replacement required during boost pump or vapor separator rebuild

📦 Condition

• Genuine Quicksilver part

• Brand new

• Supplied in original or equivalent packaging