I would check to see if you are running lean. That can cause your oil temp to rise. Too much oil in the pan can also cause higher temps. Check your oil level when you are in the water.

Dan

One other thought, there was a lot of discussion a while back about the oil bypass valves in the block. I'm not sure if the discussion will also apply to a GenV. Do a search for "oil bypass" and you'll see what I am talking about.


Crap.. never mind.. I just read the rest of your post...

This is what I found when I did the search on "oil temp":

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I quote Dennis Moore, author of "Bib Block Chevy Marine engine" He says it is perfectly normal for you engine oil to reach 260-270 degrees after a hard run. My 02 cents.


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Have a nice day.... kaama82

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I like this answer because I too just installed gaffrig oil temp guages in my twin 454 mag setup. One engine runs at about 230* at 3500. The other will run about 245* at 3500. If I start getting on it the first engine goes to about 245-250* and the other to 260*. They both drop right back down when I go back to cruise speed. I'm gonna take kaama82's answer because that fits my facts nicely. I am running Mobil 1 25-50 with fairly fresh engines.

BT

Thanks again, everyone. I have thought about a lean mixture causing high oil temp. The second time out I went up three jet sizes on the secondarys and one size up on the primarys. It improved the overall feel of the motor when pushing the throttle past halfway. I don't have enough time on the engine yet to do a WOT plug check but, I did do one at 2700 rpm the first time out and the plugs had just a hint of color. The second time, after rejetting, I did a run at 4000 for about 2 minutes. The plugs were showing a little bit of brown. I think it is still a little lean so maybe fixing that will get the oil temp down a little. Next time out I am going to run 20w-50 oil and see what happens to the pressure at idle with that. If Dennis Moore says that 260-270* is normal after a hard run than maybe I will be OK when all is said and done.