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Old 06 October 2017, 02:45   #1
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Why 2 holes

On my new to me Narwhal H450 there are 2 holes at the rear of the transom in a little sump with a double bung provided internally. Externally there is a small single bung quite a bit smaller than one of the two inside.

Is this something clever that I don't understand of is it just for draining water when on the hard

Pic attached. Yes I know It needs cleaning

Dennis
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Old 12 October 2017, 06:29   #2
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They are drain holes, which can be opened when under way to let water out. I have similar in mine, again with 2 holes. One alone doesn't let water out very quickly. They can be a pain to use and practically impossible if on your own as you have to leave the helm to operate them and when you stop, they let the water back in. I fitted a narrow elephants trunk to one of mine, which makes it easier to use. Thankfully its a very dry ride so don't have to use that often.

Phil
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Old 12 October 2017, 07:11   #3
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They are drain holes, which can be opened when under way to let water out. I have similar in mine, again with 2 holes. One alone doesn't let water out very quickly. They can be a pain to use and practically impossible if on your own as you have to leave the helm to operate them and when you stop, they let the water back in. I fitted a narrow elephants trunk to one of mine, which makes it easier to use. Thankfully its a very dry ride so don't have to use that often.

Phil

Ahhh that is why the 2 bungs are on the inside. I assume you need to do this operation at some speed hence the need for 2 people

Dennis
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Old 12 October 2017, 09:14   #4
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Ahhh that is why the 2 bungs are on the inside. I assume you need to do this operation at some speed hence the need for 2 people

Dennis
No...
Don't panic one person and certainly NOT at speed!..The BUNG/BUNGS easily taken out /replaced as needed.
Silly system in my view,and your much better off getting an Auto Bilge pump...You already have a Well for it
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Old 12 October 2017, 09:25   #5
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Even if you take the bungs out while not moving the rate water will come in is slow. Once you are up to about 5 knts there will be no water coming in. You certainly don't want anyone standing right next to the transom fiddling with those while moving at any speed!

Like Maximus says, if you want to get water out of the boat then an auto bilge pump can be had for sub-50.
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Old 13 October 2017, 06:37   #6
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You can get one way valves to go in instead of the bungs. Not sure how well they work though.
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