Oil Cooler Flow Direction
 

Does it matter what direction that the oil flows through the oil cooler compared to the direction that the water flows through it?
I thought that I read that someone was having problems with higher then normal oil temps and they reversed the flow of oil through the oil cooler and it fixed it. I find it hard to believe that would fix it but who knows.
Mike

Re: Oil Cooler Flow Direction
 

I asked the same question a few years ago and was told by a reliable source that the difference is minimal at best.

Not sure this will help answer your question very well, but just for your info, I run very large oil coolers with Kieth Eickert oil thermostats. By the looks of my coolers, the oil runs from one end to the other and then actually turns around and runs back the other way through another channel/passage ALL within the cooler itself. However, the water only seems to flow through one passage and only in one direction. I didn't know this until I actually took apart the cooler just to check it out, clean it, and inspect for any obstructions.

Re: Oil Cooler Flow Direction
 

Technically the oil should flow against the water flow. That way, the temperatur differential will always be the greatest. I know that on my setup, I have the flow reversed and have no temp problems.

Re: Oil Cooler Flow Direction
 

I had the same question, so tried it for my self. Although I didn't have a oil temp gage, I don't think it made any real dif. I'm going to install a oil temp gage and a larger cooler.

Re: Oil Cooler Flow Direction
 

I was cranking hard on the boat for about 15 mins and my oil temp reached 260 degrees, I'm running a eddie marine 3" oil cooler on a single 500hp. I removed it to inspect it for blockage, which there was none. The sea pump I just had apart and the impeller is like new and it is only a season old. I'm running approx. 25 to 30lbs of water pressure at WOT. Not sure what direction to go next.

Re: Oil Cooler Flow Direction
 

If you can afford it, try and run a large oil cooler with an oil thermostat. This way you will probably have more oil cooling availabe than what you may really need. Also, with a larger oil cooler your chances are that you won't max it out and yet have all the cooling effect that your engine requires without maxing out the oil cooler. A larger cooler will be able to keep up with the cooling demands of your engine.

Re: Oil Cooler Flow Direction
 

where are you gettin your oil temp readings from . on the out going side (engine to cooler) or the incomming side . a 3x12 oil cooler should keep the oil cool . what is the engine water temp also that has a lot to due with oil temps

Re: Oil Cooler Flow Direction
 

My sending unit is on the port side of the engine in the block right above the oil pan. Not sure before or after the cooler.

Re: Oil Cooler Flow Direction
 

Engine water temps run around the 150 to 170 range.

Re: Oil Cooler Flow Direction
 

CMS yours or anyones thoughts?