I mentioned this in passing on another post but thought it might be helpful to someone who is having issues or just wants to monitor oil temps before and after the cooler(s). I didn't see this idea posted anywhere however as I mentioned many times before, my ability to "search" for info isn't that good which is why I just ask. There are different opinions on this and probably every site about mostly everything. I started out watching the high oil temp then there were several posts that said they prefer to watch the oil temps after the cooler. I don't know who is right but I was able to satisfy both opinions. I ended up buying a second sending unit for each engine and installed them after the coolers. Both sending units and the gauges are now hooked up to DPDT switch so I can monitor both. I now know that the coolers are working properly. tgorbett had mentioned that he was or is running the same coolers and they reduce the temp by 50-60 degrees which is right where mine are. I looked several times while out yesterday and it was consistently 50 degrees or so lower. Here's the link if you care to watch. Sorry about the music.

What cooler are you running again?

It's a tube style from CP Performance and its 3"x23". It also cools the power steering. Supposed to support up to 700 hp.

To search forums on Google for example

"forum: offshoreonly.com" oil temperature gauge

Thanks for the help. I tried it and found a "Drnautica" back in 05 did the same thing. Probably others too. Lets just look at my post as a reminder. Thanks again

What water temps do you typically boat in are giving you the 50 degree drop across that cooler?

Grand River and Lake Michigan so usually pretty cool water. Water temps upper 70's in the river and low 70's in the lake.