Honda B Series Oil Pan Gasket 11251-P30-004

Genuine Honda B-Series Oil Pan Gasket (11251-P30-004)

If you're sealing a B-series oil pan, the genuine Honda OEM gasket (part #11251-P30-004) is the only replacement that matches the exact flange geometry, material durometer, and compression tolerance Honda engineered into your engine. Aftermarket alternatives cut corners on material spec, which is why you see oil seepage come back within a season on a lot of B-series builds that used a cheaper gasket the first time around.

This is a direct OEM replacement, not a rebranded aftermarket part. The rubber-coated steel construction holds its seal under the heat cycling a B-series sees in both daily-driver and track use. It compresses evenly across the full perimeter of the oil pan flange, which is the part that cheap gaskets consistently get wrong.

Why The Cheap Ones Leak Again

Worth understanding, because it's the whole reason to spend a little more here.

An oil pan gasket seals a long, thin flange with a lot of bolt holes, and the trick is even compression all the way around. A gasket made from the wrong material or to a loose tolerance compresses unevenly, sealing in some spots and leaving gaps in others. It might look fine on install and then start weeping a few heat cycles later as the material takes a set.

That's the "why is it leaking again" story people know from cheap gaskets. The OEM piece uses the correct durometer and holds its shape, so it seals evenly and stays sealed rather than relaxing into a leak. On a part that's buried under the car and annoying to redo, getting it right once is worth it.

It Seals Dry, No RTV Needed

An important install point, and one people get wrong.

Honda designed this gasket to seal dry. No gasket maker or RTV sealant is required, and adding it is actually counterproductive, since RTV can prevent the gasket from seating properly and can squeeze into the pan where it doesn't belong.

Clean the mating surfaces thoroughly, lay the gasket in dry, and torque it down. That's how it's meant to go together, and it's simpler than fighting with sealant.

Torque It Properly

The other half of a good seal.

Torque the oil pan bolts to Honda spec, typically 8-12 Nm (6-9 ft-lb) depending on the engine variant, and always verify against your service manual for your specific engine. Work in a crossing pattern rather than going around in a circle, which pulls the pan down evenly and gives you that consistent compression across the whole flange.

Over-torquing is a common mistake here. These are small bolts into aluminum, and cranking them down doesn't seal better, it distorts the flange and strips threads. Snug to spec, evenly, and it seals.

A Straightforward Job

The install runs 30-45 minutes with a standard socket set and a drain pan.

If you're already pulling the oil pan for a rebuild, rod bearing service, or oil pump replacement, this is the correct OEM gasket to have on the bench before you button it back up. There's no reason to reuse the old one when you're in there, and a fresh OEM gasket is cheap insurance against a leak that would mean doing the job twice.

Compatible B-Series Engines

B16A, B16A2, B16B, B18B1, B18C, B18C1, B18C5, B20B, B20Z

This gasket fits a wide range of Honda and Acura chassis from 1988 through 2001. See the full fitment list below before ordering.

Who Should Grab One

This is for anyone sealing a B-series oil pan, whether that's chasing an existing leak or buttoning up a rebuild, rod bearing job, or oil pump replacement. It's the genuine Honda gasket with the correct material and tolerance, it seals dry without sealant, and it stays sealed rather than weeping back a season later like the cheap ones. Clean your surfaces, torque to spec, and do it once.

Part number: 11251-P30-004. Engines: B16A, B16A2, B16B, B18B1, B18C, B18C1, B18C5, B20B, B20Z. Construction: rubber-coated steel. Install: seals dry, no RTV required, torque to Honda spec (typically 8-12 Nm / 6-9 ft-lb, verify with service manual). Type: genuine Honda OEM. Sold: individually.