Keep spray, grit, and fishing-line loops out of your mid-section with Mercury’s Lower Mount / Oil-Outlet Cover 100-8M0148785. This factory part snaps over the lower pivot boss on dozens of V-6 and V-8 outboards—from 200 hp FourStroke to 250 hp Pro XS—sealing the mount cavity so bushings stay greased and exhaust gases flow the way Mercury engineers intended.

Why the genuine cover is worth the quick swap

• Molded ABS composite—lightweight at just 0.39 lb yet tough enough to shrug off dock bumps and UV fade.

• Precision key tabs align with the driveshaft-housing slots; no filing or shim washers.

• Raised perimeter gasket ridge mates cleanly to the casting, keeping water out of the pivot tube.

• 7¼ × 4¾ in. footprint clears trim-ram boots and steering links on engines SN 1B775626 & up.

Installation is simple: two stainless #10 screws off, old cover out, new one in, torque to spec—five minutes, start to finish. The payoff? Quieter mounts, cleaner bilge, and longer life for the hardware that keeps your Mercury running smooth when you hammer the throttle. Small part, solid protection, factory fit.