Description

The Mercury MerCruiser Quicksilver 12-85058 is a genuine Mercury Marine OEM flat washer used in select MerCruiser sterndrive, transom, trim, and Mercury outboard hardware assemblies. This washer is commonly associated with anchor pin and structural mounting locations where the factory parts diagram calls for 85058 / 12-85058. It helps distribute clamp load across the hardware stack and should be matched by part number, assembly location, and serial number before installation.

Key Features

• Genuine Mercury Marine factory OEM washer.
• Mercury/MerCruiser part number: 12-85058.
• Manufacturer part number: 85058.
• Flat mechanical washer for select anchor pin, transom, trim cylinder, and mounting hardware locations.
• Listed shipping weight: 0.03 lb.
• Listed shipping dimensions: 1.75 in. L x 1.75 in. W x 0.25 in. H.
• GTIN/UPC references: 745061154544 / 0745061198524.
• Used where the Mercury/MerCruiser parts diagram specifically calls for this washer.

Application Compatibility

Common where-used application groups include select Mercury and MerCruiser assemblies by serial number and diagram location, including:

• MerCruiser R / MR sterndrive applications where specified
• MerCruiser Alpha One transom and gimbal housing assemblies where specified
• Select trim cylinder anchor pin hardware locations
• Select Mercury outboard trim, transom, powerhead, and link assembly locations where specified
• Mid-to-high horsepower Mercury outboard applications where the factory diagram calls for 12-85058 / 85058

Use this washer only where the Mercury or MerCruiser parts diagram specifically calls for 12-85058 / 85058.

Fitment Notice

Confirm fitment by engine or drive serial number, transom assembly, trim cylinder hardware stack, anchor pin location, and exact Mercury/MerCruiser parts diagram before ordering. Similar washers can vary by inside diameter, outside diameter, thickness, and load-bearing location, so matching by appearance alone is not enough.

When This Part Needs Replacement

Replace this washer if it is missing, bent, deeply corroded, distorted, cracked, grooved, flattened unevenly, or damaged during disassembly. Washers used around anchor pins, trim cylinder mounts, transom hardware, and structural linkage points should not be reused if they no longer sit flat or distribute clamp load evenly.

Installation Notes

Install this washer in the exact hardware position shown in the Mercury/MerCruiser diagram. Inspect the matching anchor pin, bolt, nut, bushing, spacer, trim cylinder eye, gimbal/transom surface, and related washers while the assembly is apart. Follow the Mercury or MerCruiser service manual for the correct hardware order and torque procedure for the specific assembly.

Alternate/Superseded Part Numbers

• 12-85058 — Mercury/MerCruiser formatted part number
• 85058 — Manufacturer part number
• SEI 9B-121-17 — aftermarket cross-reference; verify by application
• GLM 21671 — aftermarket cross-reference; verify by application

Parts Desk Insight

Anchor pin and trim hardware washers are small parts, but they matter in high-load transom and trim assemblies. The correct washer helps keep the hardware stack aligned and clamped properly, so it should be replaced when worn and matched to the exact diagram location rather than substituted with generic hardware.

Shipping: Ships same or next day for fast Canada wide shipping.