So a few weeks back I noticed my Oil was a bit milky in my 37EFI, both on the dipstick and under the valve cover near the oil fill. I talked to the mechanic that works on my engine and he said it may be a bit of fuel that forced it way in because off the fuel tank being pressurized. He recommended changing the oil before using it again. I did a full service on the engine afterwords and also cleaned out the milky oil under the valve cover. After doing this I ran the engine 10-15mins to make sure everything ran/sounded good and it seemed fine.

Fast forward 2-3 weeks and I haven't had a chance to use it since so I went over and checked to see if the issue had cleared up after the oil change. Pulled the dipstick and the oil looked perfect, pulled the valve cover under the oil fill off and there was quite a bit of fairly milky oil inside. It does have a hint of a fuelish smell to it but I'm not sure if it's the issue or not? I'm wondering if it could be water/moisture making the oil milky??

I did get my boat stuck before the issue started and had to get pulled out by an airboat....I'm wondering if somehow that caused water to be pushed in somewheres?? Any of you guys ever seen/had an issue like this before.....I'm trying to plan my next step.

Here's what the oil looks like under the valve cover....

Damn that's serious!
You need to make sure your fuel tank is vented, so its not pushing fuel through the carb if your oil does smell like gas.
You also need to make sure there is no way for water to be getting in there. Theres no way for the airboat to push water anywhere in your motor, unless you sunk the fucker.

You also have a fairly new engine and I would bring it in to get looked at. It should be under warranty.

Condensation from cold to hot in a short time or vice versa. Also quick run times and cool downs attribute to this.

That's kind of what I was thinking on the water issue also but it was a thought. There's no pressure whatsoever on the fuel tank so I'm thinking that's not the issue either. I'm just trying to think what to do next and wondering if I should just bring it in to the mechanic and see what he thinks....

No the current tank it's hooked up to is not, it's a 12 gallon tank I run first and then have the 2 stock ones in front of it with the shitty vent caps that I use as extra for long weekends.

Just talked to the mechanic he seems to think it's a minor condensation issue, and said to keep an eye on the dipstick and as long as it looks good don't sweat it.

I'm just the OCD type that worries about every detail...

Mine did that when I used to keep it in the yard. Warm days and very cold nights.

I changed oil to synthetic and didn't seem to have the problems any more.

What kind of exhaust do you have on it? Is it parked outside raining into the exhaust and draining down? A member on here had his kid think the holes in a marshmellow exhaust looked great to spray water in. hahaha

It's a stainless works exhaust and I do keep it trimmed up, but it's stays inside unless in use.

The weird thing is though the only place the milky oil is present is under the valve cover, the dipstick stays clean.

I'll probably go run it tomorrow afternoon and see if I notice any changes in performance.

Pull the valve covers of your airboat. It will look the same. Thats how it is in mine anyways. You shouldn't have anything to worry about.

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