High-performance Mercury owners know the feeling: at speed, the stock dual top mounts and plate allow a hint of engine movement that shows up as vague steering feedback and inconsistency.
 
Our Single Solid Billet Upper Motor Mount— from Buckshot Racing #77—replaces that entire dual-mount/plate stack with one precision 6061 billet aluminum block. The result is a stiffer, more predictable connection between the powerhead and midsection on all Mercury 3.0- and 3.2-liter V6 outboards.
 
Why a Single-Piece Solid Mount
Moving from dual to a single solid billet upper mount tightens the interface dramatically. Steering inputs translate directly, trim changes feel cleaner, and setup adjustments become easier to read on the water because the engine is no longer shifting on soft components.
 
Performance boats benefit most: less compliance means more precise tracking and greater confidence when you’re running hard. As with any solid mount solution, expect a bit more vibration at idle—an accepted trade-off when your priority is control and consistency.
 
Fitment and Applications
This upper mount covers the Mercury 3.0L and 3.2L families and is a direct, single-piece replacement for the two OEM upper mounts and the top plate. It fits Mercury 200, 225, and 250 3.0L models as well as the Mercury Racing 300 Pro Max, 300X, and 300XS (3.2L DFI). 
 
Construction Details
Every mount is CNC-machined from 6061 billet aluminum to maintain tight, repeatable tolerances and a long service life. The one-piece design eliminates the stacked interfaces of the OEM system, simplifying installation geometry while maximizing rigidity. It’s the cleanest way to lock down the top of the powerhead on these platforms.
 
Cross-Reference Numbers
Many owners search by OEM references tied to the factory dual-upper/plate assembly. Common numbers associated with the components our mount replaces include 8M0036783, 813769, and 8163851.
 
If you’re refreshing the entire system during service, you may also encounter 813771-1 in lower-mount contexts. Our product replaces the upper dual-mount/plate stack; keep those numbers handy to compare against catalog listings as you shop.
 
Installation and Ownership Notes
On these platforms, upper-mount service typically requires powerhead removal, which makes this an ideal time to inspect lowers, steering hardware, and fasteners. After the swap, it’s normal to notice more buzz at idle due to the absence of rubber isolation; periodic torque checks are good practice on any solid-mounted performance outboard.
 
Quick Answers
Will this work on a 300XS? Yes—the single billet upper replaces the dual top mounts and plate on the 3.2L 300XS midsection.

Do I need to change the lowers too? Not strictly. Many performance setups eventually go solid on the lowers for a fully locked geometry, but you can run the solid upper on its own if that suits your application.
 
Add two (2) Solid Lower Motor Mounts as optional.

Part numbers:  8M0036783, 813769, 8163851, 8M0036783, 813771-1
 
Contact Mike Hill at +1-714-697-1716 or email mike@buckshotracing77.com for technical support.