The 10-piece Lower Motor Mount Bolts Kit from Buckshot Racing #77 is a stainless hardware upgrade for high-performance Mercury outboards. It replaces aging factory fasteners in the lower engine mounts with corrosion-resistant components that maintain clamping force and alignment under hard use.
Built for Mercury V-6 outboards, this lower motor mount kit is ideal for bass boats, performance hulls, and jet applications where Mercury lower motor mount bolts see constant stress and exposure to water.
Hardware Specification
Each kit includes two (2) Stainless Fine-Thread Bolts that replace Mercury OEM part number 63474, with direct cross references to 86581 and 898831. These bolts are dimensionally correct for the lower motor mount saddles, providing proper shank engagement through the mount and midsection casting on Mercury V-6 engines.
The bolts are paired with two (2) Stainless Nylock Nuts that match Mercury OEM part number 82670817. The nylon locking collar resists loosening caused by engine vibration and steering loads, helping keep the gearcase and midsection locked together at high speed.
To complete the clamp stack, the 10-piece kit also includes six (6) Stainless Mil-Spec Washers equivalent to Mercury OEM part number 816056. These washers provide the correct bearing surface on the aluminum brackets, distribute load evenly, and help protect against fretting and surface damage.
Together, the stainless bolts, NyLock nuts, and Mil-Spec washers form a complete Mercury lower engine mount hardware solution that resists corrosion far better than traditional zinc-plated fasteners.
Fitment: Mercury Marine and Mercury Racing 2.0L, 2.4L, 2.5L V-6 Outboards
This Buckshot Racing lower motor mount hardware is designed for Mercury V-6 platforms using bolt 63474 / 86581 / 898831 in the factory parts book. Typical applications include Mercury 2.0-liter, 2.4 liter, and 2.5-liter V-6 outboards such as V-135, V-150, V-175, V-200, and V-220 Laser models.
Many Mercury XR2, XR4 and XR6 Magnum engines, Pro Max and Super Mag 150/200/225 EFI models, 245HP Carb, 260 EFI, 280 EFI (Long Shaft) and numerous 150 HP V-6 2.0L and 2.5L carbureted and EFI outboards share the same lower motor mount design and accept this kit.
Mercury jet outboards including 105 Jet, 115 HP V-6, 135 HP V-6, and 140 Jet variants commonly use the same lower motor mount bolt numbers and can be serviced with this Buckshot Racing #77 hardware set.
When a Mercury lower mount parts list calls out 63474, 86581, or 898831 bolts, this stainless kit is the intended replacement.
Installation & Technical Notes
Installation is straightforward for any technician familiar with Mercury V-6 midsections. The engine must be supported securely before any lower motor mount hardware is removed. Once the mounts are exposed, the original Mercury lower motor mount bolts, washers, and nuts are removed and the mating surfaces checked for corrosion or damage.
The new stainless bolts are then installed with the Mil-Spec washers arranged in the same positions used by the factory hardware. A light film of marine-grade anti-seize on the threads improves serviceability while the Nylock nuts still provide strong resistance to loosening.
Torque is brought up evenly side to side and set to the specification in the Mercury service manual for the particular 2.0L, 2.4L, or 2.5L V-6 model. Proper torque and even clamping are critical to maintaining lower motor mount integrity, improving steering precision, and preventing unwanted engine movement at speed or in rough water.
Summary
The 10-piece Lower Motor Mount Bolts Kit from Buckshot Racing #77 delivers a complete stainless replacement for Mercury lower motor mount hardware using bolt numbers 63474, 86581, and 898831, nut 82670817, and washer 816056.
Designed for Mercury 2.0L, 2.4L, and 2.5L V-6 outboards, including V-135, V-150, V-175, V-200, V-220 Laser, XR-4, XR-6, Pro Max, Super Mag, and related jet models, this kit provides durable, corrosion-resistant lower motor mount fasteners that keep powerful Mercury engines securely mounted and ready for high performance.
Contact Mike Hill with any questions at +1-714-697-1716 or mike@buckshotracing77.com