27991734 Mercury MerCruiser Gasket | Genuine Quicksilver OEM Part

🔧 Product Description

Genuine Quicksilver Driveshaft Housing Gasket - Part Number: 27-991734

A genuine Quicksilver driveshaft housing gasket used on selected Mercury and Mariner V6 2-stroke, EFI, DFI / OptiMax, Jet and high-performance outboard midsection assemblies. This gasket seals the driveshaft housing to the driveshaft housing plate / exhaust plate area.

⚙️ Key Features

• Genuine Quicksilver OEM driveshaft housing gasket

• Correct Mercury part number 27-991734

• Used in V6 outboard midsection / driveshaft housing assemblies

• Commonly listed with 27-991764 cylinder block gasket in powerhead and lower-unit gasket set components

• Important replacement during powerhead, driveshaft housing or exhaust plate service

🔄 Supersession & Cross Reference

OEM Supersession Chain:

• 27-991734 current OEM service reference

• 27-991733 / 27-991732 / 27-991731 related earlier gasket-family references where applicable

OEM / Related Numbers:

• 27-991734

• 991734

• 27991734

• 27-99173-4

• 27-991733

• 27-991732

• 27-991731

• 27-183076 related driveshaft housing plate gasket

• 26-38970 related seal

• 27-991764 related cylinder block gasket

Aftermarket / Verified Equivalents:

• WSM: 510-30 related drive housing gasket reference

🚤 Compatibility

Commonly used on:

• Mercury / Mariner V6 driveshaft housing and exhaust plate gasket applications

Typically suits:

• Engine models:

• Mercury V-135 DFI 2.5L - serial 0T801000 to 1B226999

• Mercury V-135 DFI 2.5L - serial 1B227000 to 1B417701

• Mercury V-135 DFI 2.5L - serial 1B417702 and up

• Mercury V-150 DFI 2.5L - serial 0T801000 to 1B226999

• Mercury V-150 DFI 2.5L - serial 1B227000 to 1B417701

• Mercury V-150 DFI 2.5L - serial 1B417702 and up

• Mercury V-175 DFI 2.5L - serial 0T801000 to 1B226999

• Mercury V-175 DFI 2.5L - serial 1B227000 to 1B417701

• Mercury V-175 DFI 2.5L - serial 1B417702 and up

• Mercury V-150 EFI 2.5L - serial 0T801000 to 1B226999

• Mercury V-150 EFI 2.5L - serial 1B227000 and up

• Mercury V-200 EFI 2.5L - serial 0T801000 to 1B226999

• Mercury V-200 EFI 2.5L - serial 1B227000 and up

• Mercury XR-6 / Magnum III engine gasket set applications - serial 0G960500 to 1B226999

• Mercury 150 Pro XS 2.5L - serial 1B690542 to 2B535572

• Mercury 175 Pro XS 2.5L - serial 1B516339 to 2B535624

• Mercury 200XS DFI 2.5L - serial 0T818181 to 1E000796

• Mercury 200XS DFI 2.5L - serial 1E000797 to 1E002110

• Mercury 200XS ROS DFI 2.5L - serial 1E050852 and up

• Mercury 200XS SST - serial 1E050629 and up

• Mercury 105 Jet / 140 Jet 2.5L V6 driveshaft housing applications where 27-991734 is specified

• Mercury 105HP to 225HP V6 drive housing plate applications where 27-991734 is specified

• HP Range: commonly 105 Jet through 225HP V6 applications where specified

• Engine Type: Mercury / Mariner V6 2-stroke, EFI, DFI / OptiMax and Racing outboard

• System Type: Driveshaft housing to driveshaft housing plate gasket

🔌 Function

The gasket seals the driveshaft housing interface, helping prevent exhaust leakage, water leakage and contamination at the midsection / exhaust plate area.

Common signs of failure:

• Exhaust leakage from midsection

• Water leakage around driveshaft housing joint

• Gasket damaged during powerhead or midsection removal

• Corrosion or residue around gasket surface

• Replacement required during exhaust plate or driveshaft housing service

📦 Condition

• Genuine Quicksilver part

• Brand new

• Supplied in original or equivalent packaging