Description

The Mercury Quicksilver Driveshaft / Oil Seal 26-804156 is an OEM-style radial shaft oil seal used in select Mercury, Mariner, and MerCruiser gearcase or powertrain applications. It seals around rotating shaft surfaces to help retain oil or gear lubricant while helping prevent water intrusion into the assembly.

Key Features

• Genuine Mercury/Quicksilver oil seal
• Part number: 26-804156
• Also referenced as 804156
• Radial shaft oil seal for compatible gearcase or powerhead applications
• Helps retain oil while sealing against water and contamination
• GTIN / UPC: 745061204156
• Often stocked in multi-pack service quantities for repair work

Engine Compatibility

Used on select Mercury and Mariner outboard applications, including various 2-stroke carbureted, Laser, EFI, XR4, and Magnum II engine families from roughly 35 HP through 200 HP. Also used in select MerCruiser applications, including Vazer-related powertrain assemblies where this seal is shown in the parts diagram.

Serial Number Fitment Notice

Verify fitment by engine or drive serial number, gearcase diagram, seal location, and original part number before ordering. Oil seals can vary by shaft diameter, housing bore, installation depth, and gearcase or powerhead configuration.

When This Part Needs Replacement

Replace this seal if oil or gear lube is leaking, water is entering the housing, the seal lip is worn or hardened, the garter spring is damaged, or the seal is disturbed during rebuild or shaft service.

Installation Notes

Inspect the shaft sealing surface before installing the new seal. Grooved, corroded, or pitted shafts can damage the new seal and cause repeat leaks. Install squarely with the correct driver and pressure-test the gearcase where applicable.

Alternate/Superseded Part Numbers

Primary Mercury references: 26-804156 and 804156.

Parts Desk Insight

Oil seals are location-specific parts. Matching the outside diameter is not enough—the shaft size, lip direction, and installation depth all need to match the Mercury diagram for the seal to work properly.

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