oil cooler lines: which is feed, and which is return?

so i'm using the later model block oil filter relocation thing that's found on the 740s and the 940s (not the watercooled version). Trying to figure out which of the lines go where. I understand that on one of the outlets to the oil cooler there is no resistance when you blow into it. on the other outlet it looks like there is a thermostat. If you try blowing air into the side with the thermostat you simply cant. which is the feed, and which is the return? thanks.

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also this style of oil cooler is the one that pushes the oil filter closer to the firewall. it's the pretty large one, and NOT the one that comes on the early 240s / 740s

really? no one knows?

I just checked on my stock oil-cooler setup on my '90 745. The cooler compression fitting that is AWAY from the block goes into the top of the oil cooler itself. The bottom line on the cooler itself goes into the compression fitting CLOSEST to the block. I would assume that means that the return is the fitting close to the block and the feed is the one away. Best i can do for you!

orie said:

I just checked on my stock oil-cooler setup on my '90 745. The cooler compression fitting that is AWAY from the block goes into the top of the oil cooler itself. The bottom line on the cooler itself goes into the compression fitting CLOSEST to the block. I would assume that means that the return is the fitting close to the block and the feed is the one away. Best i can do for you!

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hey thanks a bunch.

I'm now trying to figure out if the stock oil coolers have a thermostat built into them. if they don't then i guess it doesn't matter which line goes where for the oil cooler.

bumping this thread again.

I assumed since the oil filter sandwitch plate has a thermostat built in it wouldn't matter which oil line goes to what part of the stock oil cooler correct? either way one side will be sending oil the oil cooler. is this a correct assumption?