Sierra Oil Pan Gasket 18-1239, Replaces Mercury Marine 27-810846T, Fits OMC 3.0L/LX

The Sierra 18-1239 is a marine oil pan gasket engineered to seal the oil pan on OMC 3.0L and 3.0L/LX engines. It is designed as a direct cross-reference for Mercury Marine part 27-810846T, giving boat owners and marine technicians a reliable option when the oil pan needs to come off for service, inspection, or repair. The gasket is finished in white and is sold as a single unit, ready to install without additional trimming or fabrication.

A properly sealed oil pan gasket is essential to keeping engine oil contained and preventing leaks that can lead to low oil pressure, fouled bilges, or contamination of other engine components. The Sierra 18-1239 is built to the fit and dimensions of the engine oil pan it is designed for, so it seats correctly against the mating surfaces during reassembly. Because it carries a limited warranty, it is intended as a dependable replacement part rather than a universal or trimmable gasket.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-1239
• Product Type: Oil Pan Gasket
• Color: White
• Unit Count: 1
• Weight: 0.4 pounds
• UPC: 808282242954
• GTIN: 00808282242954
• OEM Cross Reference: 27-810846T
• Fitment: OMC 3.0L, 3.0L/LX

Fitment

Fits OMC 3.0L and 3.0L/LX engines.

Replaces (OEM)

27-810846T (Mercury Marine)

Frequently Asked Questions

What engines does the Sierra 18-1239 oil pan gasket fit? The Sierra 18-1239 fits OMC 3.0L and 3.0L/LX engines.

Is the Sierra 18-1239 the same as Mercury Marine 27-810846T? Yes, the Sierra 18-1239 is a direct cross-reference for Mercury Marine part number 27-810846T.

What color is the Sierra 18-1239 oil pan gasket? It is white, matching the finish used on this Sierra oil pan gasket.

How much does the Sierra 18-1239 weigh? The Sierra 18-1239 oil pan gasket weighs 0.4 pounds.

How many gaskets come in a package of the Sierra 18-1239? Each package of the Sierra 18-1239 contains one oil pan gasket, sold as a single unit.

Does the Sierra 18-1239 come with a warranty? Yes, the Sierra 18-1239 oil pan gasket is backed by a limited warranty.

Can I use the Sierra 18-1239 as a genuine equivalent to the Mercury Marine part? The Sierra 18-1239 is manufactured as a cross-reference replacement for Mercury Marine 27-810846T, intended to fit and seal in the same application.

What is the UPC for the Sierra 18-1239 oil pan gasket? The UPC for the Sierra 18-1239 is 808282242954.

Will the Sierra 18-1239 fit a 3.0L/LX engine specifically? Yes, the 3.0L/LX designation is one of the two fitments listed for the Sierra 18-1239 oil pan gasket, alongside the OMC 3.0L.

When would I need to replace the oil pan gasket on my OMC 3.0L engine? An oil pan gasket like the Sierra 18-1239 typically needs replacement when the pan is removed for service or when it shows signs of an oil leak at the pan mating surface.