what are these holes for ????

Alrob

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I have these holes on port & starboard passageways that are connected underneath to 12mm pipe which disappear into the hidden depths - can anyone enlighten me what they actually do
 
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the water drains out of scuppers down the gunwales, these holes seem to disappear into the bilges, but that cant be as it would soon fill the bilges !!!!!!!!!
 
You could dye some water,(blue comes to mind, but there may be a better colour), pour it down the hole/s, and see if it comes out in the bilges, or over the side somewhere, or elsewhere.
 
12mm pipe sounds too small to drain alot of fluid.
Are they vents for air from below, perhaps from a tank(s).
12mm is similar to fuel tank vent but not with a deck outlet pointing skywards

I have no real idea but I like to guess!
 
12mm pipe sounds too small to drain alot of fluid.
Are they vents for air from below, perhaps from a tank(s).
12mm is similar to fuel tank vent but not with a deck outlet pointing skywards

I have no real idea but I like to guess!

Unlikely to be a vent as any water on the deck would enter it. It has to be a drain.

Have you tried pouring water into it and seeing if it actually drains?
 
I would say they are deck drains, on my boat there are low points on the side decks when the boat is at rest rain water gathers here and it drains down and comes out over the side by the engine room air intakes.

I am sure they would ( should) not drain down into the bilge.

Poor some full cream milk down the hole, if it does not come out over the side you will find it inside the hull in a week or more, easily, just follow your nose.
 
I have these holes on port & starboard passageways that are connected underneath to 12mm pipe which disappear into the hidden depths - can anyone enlighten me what they actually do

I would have thought that on your style of vessel that it would be a small deck drain, it will probably be attached to a through hull below the rub rail at the stern of the vessel.

Tom

PS Check the seam to the right in the photo, if thay stay wet for a long time after rain they normally have to be redone as the water is holding between the plank and the mastick !
 
I'd guess they are vents for the holding tank. No where near big enough for drainage holes and why drain into the bilge?

Vents are not usually placed so that they can take in deck water. If it is a vent, either it will allow water into whatever it is venting or, if it has a U bend, then the bend will fill with water and stop the venting activity.
 
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I'll say it again. Vents are not usually placed so that they can take in deck water. If it is a vent, either it will allow water into whatever it is venting or, if it has a U bend, then the bend will fill with water and stop the venting activity.

Wouldn't you agree it's a tiny aperture for drainage though? Could it be a vent for something else where it doesn't matter if small amounts of water get through - maybe something to do with the heads?
 
Stick some bungs in the holes and keep flushing the loo. See if the water in the loo slowly stops draining as presssure builds in the holding tank. Or...as someone flushes the loo stick your nose over the hole and take a deeeeeeep breath. :p
 
thanks for all suggestions chaps, clearly more detailed pics and invetigations are required, I will post more info soon


cheers
 
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