The Buckshot Racing #77 1.2mm Mercury 2.5 Liter V6 cylinder head gasket is designed for compatible Mercury and Mariner 2.5L two-stroke outboards using the 822844-series gasket pattern.
At approximately 1.2 mm / 0.0472 inch thick, this gasket provides a practical sealing thickness for stock rebuilds, performance refreshes and modified 2.5L Mercury V6 engines where the correct head-gasket pattern and final assembled clearance have been verified.
This gasket belongs to the same application family as Mercury 27-8228441, with later Mercury supersessions including 822844T04 and 822844T05. Mercury parts listings show 822844T05 superseding 8228441, while aftermarket catalogs cross-reference the same family to 18-3864, 184721, 35870, 822844, 8228442, 8228443 and 9-63854.
Correct Fitment for Mercury 2.5L V6 Engines
This gasket is for compatible 2.5 Liter Mercury and Mariner V6 two-strokes, not the earlier 2.4L 41246 / 41247 / 96543 gasket family.
Verified application listings include many 135 HP, 150 HP, 175 HP and 200 HP 2.5L V6 engines, including XR6, Pro Max and selected SportJet configurations. One current application listing specifically identifies 175 HP 1992–2002, 200 HP 1992–2005, 200 Pro Max serial ranges, XR6 1992-and-later, and 175 SportJet 1997–1999 applications.
Mercury diagrams also show 822844T05 / 8228441 used with later 2.5L cylinder-head assemblies, confirming this as a 2.5L gasket family.
Because Mercury used multiple head castings and gasket patterns across similar horsepower ranges, fitment should always be confirmed by engine serial number, cylinder-head casting, bore size, and original gasket pattern, not horsepower alone.
AFM 1.2mm Material
The Buckshot Racing #77 gasket is manufactured from AFM 1.2mm gasket material for stable sealing under repeated heat cycles, combustion pressure, cooling-water exposure and clamp load.
On a Mercury 2.5L V6, the head gasket must seal each combustion chamber while also maintaining separation between the cylinder bores and surrounding cooling passages. Surface condition, bolt clamping force, head flatness and gasket thickness all contribute to reliable sealing.
For performance engines, gasket quality becomes even more important because higher cylinder pressure and sustained RPM increase the demands placed on the head-to-block joint.
Why 1.2mm Thickness Matters
A 1.2mm gasket measures approximately 0.0472 inch.
Head-gasket thickness affects combustion-chamber volume, compression ratio and piston-to-head clearance. A thinner gasket generally reduces clearance and can increase compression, while a thicker gasket adds clearance and generally reduces compression.
For that reason, a 1.2mm gasket should not be selected simply because it is thinner or thicker than another option. The correct thickness depends on the actual engine combination, including deck height, piston position at TDC, cylinder-head machining, chamber volume, fuel octane, ignition timing and intended RPM range.
Buckshot Racing #77 offers multiple gasket thicknesses for 2.5L applications because race and performance builds may require different final clearances. Our current 2.5L gasket lineup includes 0.75mm, 1.0mm, 1.1mm, 1.2mm, 1.3mm, and 1.5mm options.
Common search and replacement numbers associated with this Mercury 2.5L head-gasket family include:
27-8228441, 8228441, 822844, 822844T04, 822844T05, 822844004, 8228442, 8228443, Sierra 18-3864, 184721, 35870 and 9-63854.
The earlier 41246, 41247T01 and 96543 references belong to a different gasket family and should not be used as cross-references for this 8228441 2.5L gasket.
Buckshot Racing #77 Tech Tip
Do not order a Mercury V6 head gasket by horsepower alone. Before assembly, verify the engine is using the 2.5L 822844-style gasket pattern, then inspect the block and cylinder heads for corrosion, erosion, warpage or damaged sealing surfaces.
For any performance build, measure final piston-to-head clearance rather than relying only on nominal gasket thickness. Also confirm fuel quality, compression, timing and cooling-system condition before increasing compression.
If both cylinder heads are removed, the Mercury 2.5L V6 requires two head gaskets, one per bank.
Contact Mike Hill at mike@buckshotracing77.com or +1-714-697-1716