Your deeper into the engine than I have experience with?
That is labeled as a "Anti-Drain back Valve" in the manual but the picture and description make no mention of how it's to be installed?
Item 2 in the below diagram.
The only other mention I can find "might" help as I think it tells you which way the valve will let the oil flow up and into the oil cooler.
The way I read the above is the oil can go into the oil cooler BUT it can't flow back down towards the oil pump. So make sure the flow is checked going down into the block.
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