Mystery Fitting. Need help Identifying it.

[Osprey69]

I have never seen this before. The fitting beneath the diesel fill. Cannot be unscrewed and it has no visible vents or holes.

Anybody know what it is?

Thanks in advance.

 

[CharlieO.]

Looks like a hydraulic line fitting.

Could be a quick connect for something.

 

[High Wire]

Can you look behind it?

 

[Osprey69]

Charlie -Nothing moves.

High - No.

Thanks.

I have been around boats for over 50 years (OK...mostly sailboats) and I have never seen one.

 

[CharlieO.]

It would move when you push The appropriate hose fitting onto the receptacle. Usually for hydraulics there would be two, a supply and return.

Only that nipple in the center will move to allow flow once hooked up.

You haven't found any mystery hose?

My other thought is maybe it is plumbed into your fuel tank due to the location near your fill.

 

[TowLou]

Sure looks like a fuel or pressure fitting. What is behind it? What kind of fittings and plumbing?

 

[Circumnavigator]

It looks like a hydraulic quick disconnect, see https://www.mcmaster.com/95825K23/


Jim

 

[Osprey69]

Thank you Circumnavigator! That's got to be it.

Which leads me to my next question.

Why a hydraulic fitting?

Where the fuel fill hose enter into the engine room it is impossible to contort my 6' 4"ness to tend a few things including solving this riddle.

Need to hire a smart kid like I have done in the past.

 

[diver dave]

a broken one of these? Is a upper antenna support possible in the given position?

 

[RT Firefly]

Greetings,
Mr. O. Take out the three screws and try to gently pull the fitting out. There may be enough slack to examine the backside and lead you to a less speculative answer. Of course, re-bed with butyl tape.

 

[IRENE]

I will be the outlier and say it is for a washdown hose, either plumbed into the fresh water system OR with its own pump. I seem to recall seeing these in the (way) past. I will try to locate an example online.

 

[IRENE]

Sam 's Marine Inventory

 

[IRENE]

Maybe dockside water connection, instead of washdown. I think Hatteras used them.

 

[Osprey69]

DD...not broken. Complete cast.

RT...that's my next move.

Irene...not a dockside water connection. That is elsewhere.

Thanks to all for your input.

 

[KnotYet]

In my industry we use those fittings on our propane connections and hoses.
My logical brain would want to group flammables plumbing near one another and
away from water connections which makes me want it to be fuel, oil or propane.

If the installation adheres to typical practice, then that fitting would 'receive' the
pressurized fluid. Does your boat have hydraulic powered windlass or thruster(s)?

 

[twistedtree]

I agree that it's a hydraulic quick connect, or at least the male half. But it's probably not used for hydraulics unless there is also a return fitting somewhere. Possibilities include:


1) A fuel transfer port for moving fuel from an on-deck badder into the main tank(s).


2) Quick connect for a built-in pressure washer. These run at a pretty good pressure, so the pressure rating of a hydraulic disconnect would make sense.


It seems overkill for a water fill or lower pressure washdown.

 

[IRENE]

Another source for the female half:

https://www.boatownerswarehouse.com/product_p/106870.htm

 

[IRENE]

Here are a couple of examples on a 54 Hatteras from the 1990s:

 

[chriscritchett]

I’m guessing SW of FW wash down connection, unless you have those elsewhere. Yes, overkill for a low-pressure connection, but also convenient.

 

[CharlieO.]

Nice Jeff, in your pics it's labeled as fresh water washdown.

 

[Iggy]

Some times hydraulic connectors are used for fuel polishing. That could be the out flow and the in would be the fill opening. Just a thought?

 

[psneeld]

Post #1 and #18 have pictures that I would guess most people would say answer the question.

Any further wild guessing may suggest you are one of the ones that never reads most or all of the threads.....

Granted it's not absolute, but without looking behind it, we may never know..

 

[Circumnavigator]

Thank you Circumnavigator! That's got to be it. ...

Where the fuel fill hose enter into the engine room it is impossible to contort my 6' 4"ness to tend a few things including solving this riddle.

If it's really hydraulics, then it might be hose or hard pipe. In either case you might be able to figure out which hose or pipe came from that area that you can't otherwise account for.


I like the suggestion that you pull it out a bit and see what connects to it. If it has a typical band hose clamp, it's not hydraulics. If you can see the hose, that will help with my suggestion above.


Jim

 

[Osprey69]

In my industry we use those fittings on our propane connections and hoses.
My logical brain would want to group flammables plumbing near one another and
away from water connections which makes me want it to be fuel, oil or propane.

If the installation adheres to typical practice, then that fitting would 'receive' the
pressurized fluid. Does your boat have hydraulic powered windlass or thruster(s)?

Beside steering, no hydraulics on the boat.

 

[Osprey69]

Post #1 and #18 have pictures that I would guess most people would say answer the question.

Any further wild guessing may suggest you are one of the ones that never reads most or all of the threads.....

Granted it's not absolute, but without looking behind it, we may never know..

No wild guessing. Hence my post #8 regarding Circumnavigators post #7.

I will carefully remove and hopefully make a determination shortly.

 

[psneeld]

No wild guessing. Hence my post #8 regarding Circumnavigators post #7.

I will carefully remove and hopefully make a determination shortly.

Didn't mean you....just all the posts after a HUGELY possible explanation was given as I posted.

The fitting WAS used by Hatteras as a washdown...but as I also added, till you know what connects to it...maybe nothing, then it is still a mystery....

....but very unlikely to be many of the guesses. Like you have posted, no hydraulics. Even if it has been repurposed, you won't know till you pull it out if you can't locate what attaches to it any other way.

 

[lwarden]

How about turning on all water systems and pushing in the button in the middle and see what comes out?

 

[Nick F]

+1, lwarden !

 

[wkearney99]

How about turning on all water systems and pushing in the button in the middle and see what comes out?

Have some rags and a bucket handy in case it's not water. No point making more work for yourself cleaning up if it's hydraulic oil or something else.

Me, I'd back off the fitting from the surface and see what colored hose is connected on the back. Then look below/toward where a hose would be feeding to that area. Find the matching hose and track down where it goes.

 

[Osprey69]

So pulled the fitting and here it is pulled out as far as it will go...