Spot the boat component

MapisM

MapisM

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Understanding wtf the thing is hard enough to deserve a virtual cigar.
But bonus point are available for whoever will guess its function!
Anyone up for the challenge...? :)
ouq5RGsP_o.jpg
 
LOL, nice try.
Can you also explain why someone should build a bottle opener in bronze and attach it to a hull bottom...? :D
 
MapisM said:
Understanding wtf the thing is hard enough to deserve a virtual cigar.
But bonus point are available for whoever will guess its function!
Anyone up for the challenge...? :)
ouq5RGsP_o.jpg
Click to expand...

It’s a raw water inlet scoop with the filter bars removed for some reason.
 
dpb said:
Thats easy..........saves crawling out from under the boat when doing your antifouling and need that beer!!!!
Click to expand...
He’s right. I was watching some anti fouling work the other day and there were a lot of beer breaks
 
ARE said:
It’s a raw water inlet scoop with the filter bars removed for some reason.
Click to expand...
Ok, there goes the virtual cigar, congratulations! :encouragement:

Extra bonus points remain to be awarded, though.
Any guesses about what the "some reason" is? Which is the VERY difficult part, tbh.
Small hint: not accidental at all - it's purposedly factory modified, in fact.
 
MapisM said:
Ok, there goes the virtual cigar, congratulations! :encouragement:

Extra bonus points remain to be awarded, though.
Any guesses about what the "some reason" is? Which is the VERY difficult part, tbh.
Small hint: not accidental at all - it's purposedly factory modified, in fact.
Click to expand...

Outlet instead of inlet?
 
If the higher side is towards the bow and the boat is moving forward would it not create a pressure difference and draw whatever is on the other end down the pipe, sort of fuctioning as a pump....?
 
MapisM said:
Getting warmer! but why not use a plain vanilla round outlet?
Click to expand...
Builders often put them wrong way round to create suction (at P speed) for the outlet. A normal plain outlet risks having positive pressure in a P boat. (Not in a Porto boat of course :-/)

This is normal so I don't understand why you are making a big deal of it. Maybe because you are new to P boats :D. I have several "wrong way round scoops" on my boat eg for genset separated water outlets where suction is nice. Removing the bars creates even more suction, supposedly.
 
Ok, I'll spill the beans - I understand that there's no way anyone will ever earn the bonus points... :rolleyes:

Anyway, just for the records, I didn't want to make a big deal of this at all.
In fact, I already noticed the "ungrilled" and reversed inlet installed on my boat when I bought her (as well as the genset outlet, as jfm said - whose bars are NOT removed), and I didn't bother checking further.
Knowing that the outlet is for the black water tank, I just thought that the bars were removed to avoid any obstruction, but I didn't wonder why they didn't use a plain round outlet instead.
Suction effect at speed doesn't make much sense anyway, for a black water discharge.
Only today and incidentally, I was explained that the use of that modified and reversed inlet was driven by its position, in the bow section of the boat, which can be subject to high seawater backpressure while hitting waves, potentially pushing sea water back inside the tank.

Now, don't ask me how relevant/critical such risk is (instinctively, I'd say not much, if I'm honest...), but I found the fact that someone considered it, and went as far as fitting a modified inlet to be rather safe than sorry, rather remarkable.
Btw, the guy who explained me this is an engineer who has seen boats from just about any imaginable yard, and he told me that this setup is pretty unique, which is the reason why I thought it was worth asking about it here in the asylum...
Pretty sure it's not going to be the first time a geeky solution of questionable relevance is being posted around here, anyway! :D :p
 
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MapisM said:
Ok, I'll spill the beans - I understand that there's no way anyone will ever earn the bonus points... :rolleyes:

Anyway, just for the records, I didn't want to make a big deal of this at all.
In fact, I already noticed the "ungrilled" and reversed inlet installed on my boat when I bought her (as well as the genset outlet, as jfm said - whose bars are NOT removed), and I didn't bother checking further.
Knowing that the outlet is for the black water tank, I just thought that the bars were removed to avoid any obstruction, but I didn't wonder why they didn't use a plain round outlet instead.
Suction effect at speed doesn't make much sense anyway, for a black water discharge.
Only today and incidentally, I was explained that the use of that modified and reversed inlet was driven by its position, in the bow section of the boat, which can be subject to high seawater backpressure while hitting waves, potentially pushing sea water back inside the tank.

Now, don't ask me how relevant/critical such risk is (instinctively, I'd say not much, if I'm honest...), but I found the fact that someone considered it, and went as far as fitting a modified inlet to be rather safe than sorry, rather remarkable.
Btw, the guy who explained me this is an engineer who has seen boats from just about any imaginable yard, and he told me that this setup is pretty unique, which is the reason why I thought it was worth asking about it here in the asylum...
Pretty sure it's not going to be the first time a geeky solution of questionable relevance is being posted around here, anyway! :D :p
Click to expand...
Hmm. Not sure I'd give that boat builder any virtual cigar. If there is risk of sea entering in waves then that solution is not good enough. No way is it "safe not sorry". I would never accept that on a build, but I suspect I am very much not alone and that is why it is "unique". Only proper way to do a holding tank outlet anywhere but especially in the bow is to have a seacock just inside the hull and open it only when pumping out. Ideally an electric seacock for convenience.
 
jfm said:
Ideally an electric seacock for convenience.
Click to expand...
Why, is that what you've got? Possibly on gensets too? Watermaker? Straight out bypass for WCs? If so, well, wow!

Of course there is also a valve directly attached inside the skin fitting - actually, I've got valves even on above w/l discharges, a setup which, while surely not unique, is not widely adopted either.
In fact, I half remember to NOT have seen them on a couple of FLs (Sq55/58), or is my memory mixing that up with some other boat? Happy to be corrected.

Anyhow, I guess the assumption behind that solution was that nobody cares opening/closing the valve manually every time you need to pump out. I for one surely don't, and I have a funny feeling to be in good company...! :rolleyes:
So, avoiding/reducing at least the dynamic water pressure is better than nothing, I reckon.
I did classify it as "geeky solution of questionable relevance", anyhow!
 
Interestingly our discharges are below the WL but in the transom .
So when running they are in the air so to speak , the immediate void behind the hull .
Bilge pump manifold , black tank exit .
Seacocked but normally open and to empty the tank just flick a switch .

View attachment 71367

Middle hole is black discharge .
 
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