Unusual oil leak on thru hull?

[Fishtales]

Hydraulics are usually not vented in any manner. I saw that "Helm" description on the boat thru hole diagram but that is a pretty generic term. Could be anything at the helm. I'm almost positive that it is he fuel tank.

 

[wspitler]

I wasn't thinking that the hydraulics were vented, but, if it is like my 330, the area behind the helm is drained of condensation, rain water, spillage, etc. Not sure why they would label it helm if it was fuel tank vent, but could be a diagram error I guess. If it is from the helm, it surely needs attention. It should be easy to tell if the fluid is petroleum based or water based to rule out the head.

 

[DennisG01]

It is definitely a vent, not a drain. A drain is completely open like the one below and aft of the one in question.

If it was a head vent, there would be a head pump-out fitting (deck plate) nearby... can't quite see the top of the gunwale enough, though.

 

[Doc Stressor]

That's your fuel tank vent. It's designed to prevent water intrusion. The discoloration is likely the result of using a fuel additive such as RingFree in your gas.

Attwood Fuel Tank Vent

 

[DennisG01]

Just wanted to point out that while it's "fun" to talk about it being a head vent, there really is no way it could be a head vent. The head, itself, would overflow before the vent does.

Fuel vent. But just to reiterate, this shouldn't be happening with the newer fuel systems. Not good.