I just bought a new Mr. Cool oil /p.s. cooler. I have seen a post on this question but am having problems locating it. Do you guys recommend pluming the cooler so that the oil enters closer to the cooler where the water enters (from the sea pump) or to the "npt" further down todwards the p.s. section of the cooler first? Also, is it best to have water from the sea pump enter the motor oil section or p.s. section of the cooler first? Thank's guys, just trying to find out and set up this cooler so I can get the most from my oiling system.

I was told by a engine builder to flow the oil against the flow of water. Thats how I plumbed my Mr. cool cooler. Im sure other people will chime in. I have water flow go thru oil section first. Even though I can't see how it would make a big difference.

whoya, thanks for your reply and a much better way of putting my question! Thank you!....."should the oil in the cooler flow with or against the flow of water in the cooler".