[HWYSTR455]

That looks like a rear main seal to crank leak to me, and seems like it's a big one, but hard to say not being there.

It kind of doesn't matter, regardless, the pan has to come off.

I too would need to know if the serrations are present. That looking like an OE crank tells me they are. I understand that the BOP seal can be used with serrations, but believe you have to knock them down some first.

Personally, I would use a Best rope seal.

At this point, sadly, you probably would be best to pull it. You can inspect other aspects of the build that way too.

Is it a 400 block?


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