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svranjic
04-11-2010, 02:32 PM
Gday

Just starting to work my way through a new boat fit out after finishing paint and transom.

There was no bilge pump placed underneath the floor by the boat builder when the boat was built. There is no access underneath the floor so I would assume it is fully sealed..... except minus any scuppers or self draining bungs.

What should I do? Place a bilge pump at the lowest part of the boat that is above the floor or purchase some of the self draining bungs available at bias boating etc???

Cheers

Shane

TheRealAndy
04-11-2010, 03:16 PM
My experiences with self draining bungs has been bad. They always seem to leak. Get a bit of dirt or sand in and they never seal again.

dreemon
04-11-2010, 05:03 PM
The way I did mine was cut 2 large holes either side of where the centre stringer is and fitted water tight inspection hatches, then fit bilge pumps both sides of the stringer as far back as I could and wired them both to the same switch,

Doing it this way you still have a sealed floor but the problem I had is at the boat ramp one day I got swamped (an idiot in a big cruiser ) and couldnt use the pumps as the water was on the deck ,40-50 Litres and hatch covers under the carpet,

So then fitted 2 large bungs at the lowest area near the transom so if or when I need to drain the deck while on the water I can open the bungs and let it drain to the bottom of the hull to get pumped out , Cheers

deckie
04-11-2010, 06:26 PM
If you're now happy and confident with the hull's integrity there's probably only 1 decision...one pump or two. An inspection plate thats easy access underneath at the back and a decent subfloor pump ...or if the hull and deck are solid i;d just put one above floor pump in right down the back hooked up to the dash with a momentary+on+off switch.
Without knowing the rig the sealed deck was probably an essential original safety design feature itself combined with other things. If happy there's really no reason to go cutting holes in the deck i reckon.
Check out where your tanks and other stuff goes at the inside transom and perhaps position a single manually operated small-med 1000-1500gph pump on the deck at the transom...outlet to the side about 200-300mm from the back. Your risk is probably moreso green water over the back with a following sea, swamping from some extraordinary event such as Dreemon had above, plus..and dont laugh...u need protection from yourself i.e. leaving the bungs out once every 20yrs when you arnt with it. In all cases the pump isnt big enough to quickly fix a problem but will be a huge help getting u out of trouble or making it easier on you to get it back on the trailer. Plus if u want a small deckwash one day you'll need it. Handy also for simply getting rid of rainwater if stuck out in the rain. No great reason to go chopping up a perfectly good deck is there ? Just make sure the switch on the dash is closer to the sides where u can reach in and switch on from outside at the ramp. Just thinking of my own stupidity ;D
I'd steer clear of the self draining bungs too.

Horse
04-11-2010, 06:51 PM
Always have one in the hull void unless its foam filled. I hit something last year off Shag rock that left a nice hole in the bow. Luckily it was out of the water when back on the plane. A few inches lower and I would have been relying on my 1500gph in hull pump. I also have a pump on a float switch in a sump that drains from the deck. You can never have too many pumps and its not a nice feeling standing ankle deep in water waiting for it to pump out.
The self bailers seldom work effectivly and I would only use them above decks on a self draining hull

Fed
05-11-2010, 05:47 AM
Someone should make a bung that can be opened from inside the boat, some sort of tap or something.

Chimo
05-11-2010, 07:55 AM
Fed

Funny you should mention the desire for a bung that can be opened from inside the boat!

David Payne of past Express Alum boats and current Better Boat long boat fame did such a thing years ago on the Express.

The bung was located in the bottom of the hull just in front of the transom and on the outside of the hull was a Vee shaped cowl so that there was a large low pressure zone created that literally sucked water out at an amazing rate.

Damn brilliant system that was especially good at clearing the water that flooded in when you launch with the bung out. Never really needed to use it otherwise as they were a very dry boat.

Neighbour has a Better long boat sitting at his place at present, must check and see if payne still does the same thing especially as it was his personal boat previously.

Cheers
Chimo

TheRealAndy
05-11-2010, 08:13 AM
Someone should make a bung that can be opened from inside the boat, some sort of tap or something.


All our yacht club rescue boats have the bung on the inside! We just use standard bungs, and screw them on the inside of the boat!

This came about from an old abalone tinny we had. It was that shagged and use to leak so much water we put a small plumbing fitting on the inside. When it got to full of water someone layed down the back, unscrewed the bung whilst the other person drove the boat. Quickest way to empty it out!

Noelm
05-11-2010, 08:37 AM
internal bungs are not a new invention, plenty have done it before, it is just "traditional" to have them screw in from the outside, usually I guess because in the back of most small boats there is batteries, petrol tanks and god knows what else, so getting to them from the inside is uaually not easy.