Sierra 18-2624 Lower Unit Seal Kit, Replaces 26-85090A2, Mercury Outboard Gearcase

The Sierra 18-2624 Lower Unit Seal Kit is a gearcase seal kit built to restore a tight, leak-free lower unit on applicable Mercury outboard applications. Lower unit seals are a wear item: as the gearcase heats and cools through use, the rubber sealing lips lose their set and begin to weep gear lubricant or let water intrude, which left unaddressed can lead to contaminated gear oil and bearing or gear damage. This kit bundles the individual seal components needed to reseal the gearcase in one job rather than sourcing each seal separately, including an oil seal (Sierra part 18-0579) among its contents. Each Sierra seal is manufactured to meet or exceed the fit, finish, and performance of the original equipment part it replaces, so the kit installs and seals the same way the OEM components did. It is designed as a direct cross to Mercury/Chrysler service number 26-85090A2, making it straightforward to identify against an existing parts diagram or an old seal kit box. As with any gearcase reseal, use the round shape and included seals in the positions specified for your particular lower unit, and always fill and check gear lubricant after reassembly to confirm the seal job holds under pressure.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-2624
• Category: Mercury Outboard Gearcase Seal Kit
• Shape: Round
• Color: White
• Unit Count: 1 kit
• Weight: 0.2 pounds
• Kit Contents: Oil Seal (Sierra 18-0579)
• UPC: 808282243678

Fitment

Fits applications using Mercury/Chrysler lower unit seal number 26-85090A2.

Replaces (OEM)

• 26-85090A2

Frequently Asked Questions

What does the Sierra 18-2624 Lower Unit Seal Kit fit? The Sierra 18-2624 Lower Unit Seal Kit is designed as a direct replacement for Mercury/Chrysler lower unit seal number 26-85090A2, making it suited to gearcases originally sealed with that OEM part.

What OEM part number does 18-2624 cross to? Sierra 18-2624 crosses to OEM number 26-85090A2, so you can match it against that number on an existing parts diagram or old seal kit packaging.

What is included in the Sierra 18-2624 kit? The kit contains the oil seal (Sierra part 18-0579) along with the other seal components needed to reseal the lower unit gearcase in a single job.

How much does the 18-2624 seal kit weigh? This Sierra lower unit seal kit weighs 0.2 pounds.

What shape and color are the seals in this kit? The seals in the Sierra 18-2624 kit are round and white in color.

Is the Sierra 18-2624 equivalent to the original Mercury seal kit? Yes, Sierra manufactures the 18-2624 kit to meet or exceed the quality of the original equipment seal kit it replaces, specifically OEM number 26-85090A2.

How many kits come in one order of 18-2624? One order of Sierra 18-2624 includes a single seal kit, listed as a unit count of 1.

Is the 18-2624 kit genuine Sierra or aftermarket? The 18-2624 is a Sierra-branded aftermarket seal kit engineered to meet or exceed OEM specifications for the 26-85090A2 lower unit seal it replaces.

Why would I need to replace the lower unit seals on my outboard? Lower unit seals lose their sealing set over time and use, which can let gear lubricant leak out or water intrude into the gearcase; the Sierra 18-2624 kit provides the seal components to reseal the unit and prevent that contamination.

What should I do after installing the Sierra 18-2624 seal kit? After installing the seals from the 18-2624 kit, refill the gearcase with the correct gear lubricant and check for leaks to confirm the reseal is holding.

Does the 18-2624 kit include the oil seal separately or as part of the set? The oil seal, Sierra part 18-0579, is included as one of the components within the 18-2624 lower unit seal kit.

What is the UPC for the Sierra 18-2624 seal kit? The UPC for the Sierra 18-2624 Lower Unit Seal Kit is 808282243678.