Northcraft sub floor flooding

woodski · 12 July 2014, 07:50

I have a problem with my Northcraft 6,2 flooding below the deck and have tried to bilge pump it by installing a rule bilge pump with little success.It is very hard to gain access to the compartment .I have been able only to shove it in through where the cables go and push it forward.

When I trailer the rib and I take out the bung a good 10 mins worth of water decants itself..This I guess may amount to 200-300l..Therefore a considerable weight... it affects the boat getting on the plane and increases the consumption.

I am resisting the temptation to bore an access hole through the deck.Does anyone have any better suggestions ?

Woodski

Pikey Dave · 12 July 2014, 09:57

If you're taking so much water, there's summat seriously wrong. I'd be more concerned about how it's getting in & stopping it, rather than pumping it out.

jambo · 12 July 2014, 10:33

I agree with Dave. Does it take on the same amount of water no matter what sea state?

Sent from my iPhone using RIB Net

Mollers · 12 July 2014, 10:37

Quote:

Originally Posted by Pikey Dave

If you're taking so much water, there's summat seriously wrong. I'd be more concerned about how it's getting in & stopping it, rather than pumping it out.

Defo! Checking bung fitting (hull drain plug), bow eye fitting or anything else which has been fitted which required drilling either floor or hull. You really don't want water in there.

You could try recovering the boat onto the trailer when you know that there's water in there and try to see where it's coming out from.

Bigmuz7 · 12 July 2014, 12:38

Taste it to see of its salt or fresh after a dry run .. that amount would sound like salt to me .. if its fresh, thats a lot of rain water, and its getting in round your fixtures and fittings. I had a 6.2 NC that did this and it was a pain.

Fitting a bilge pump helped but they always got shaken to bits and the day you didnt check to see it was alright, was the day it rained like sh*t .. and the pump casing had split

woodski · 13 July 2014, 13:23

Water is not getting in via the bung as it does not leak when trailered then when bung removed it pisses out.I suspect water is getting at back of the rib where 2 stowage lockers are. There is bit of cracking around these in glass fibre which I have repaired a couple of times. When recovering divers or in heavy seas there can be quite a lot of water which drains to a sump and the bilge pump in there deals with it no problem
Thats why i am trying to pump it out below deck but cannot quite locate the pump because of limited access.

Exe treme · 13 July 2014, 17:36

Hi
Please remember the pressure against the bung below the water line will be far greater than a few litres from the hull, so don't discount bung/hull fittings.

Mollers · 13 July 2014, 18:50

Quote:

Originally Posted by woodski

Water is not getting in via the bung as it does not leak when trailered then when bung removed it pisses out.I suspect water is getting at back of the rib where 2 stowage lockers are. There is bit of cracking around these in glass fibre which I have repaired a couple of times. When recovering divers or in heavy seas there can be quite a lot of water which drains to a sump and the bilge pump in there deals with it no problem
Thats why i am trying to pump it out below deck but cannot quite locate the pump because of limited access.

Again, you need to stop it getting in there, rather than pumping out when it does.
Working through and addressing the possible areas of ingress would be my approach.
It maybe worth taking the bung and bung surround out, checking the O ring and resealing it back in with sikaflex when the area is totally clean and dry. Replace the bung if you're unsure of its health, they're not expensive.
If that doesn't fix it, move on to those cracked boxes.

Downhilldai · 13 July 2014, 20:22

Flood the deck, connect a bellows pump to the drain plug hole and pump away while looking for bubbles.

Mollers · 13 July 2014, 21:24

Quote:

Originally Posted by Downhilldai

Flood the deck.....

Wasn't there a video somewhere of you demonstrating how to flood a Northcraft deck whilst sat in it?

ShinyShoe · 13 July 2014, 21:51

I've used a 12v car tyre pump connected to hose pipe
. pipe pushed through bung and sealed with plasticine.

Turn on pump. Work round every seam and fitting with soapy water... I found a fitting that had been put in without sealant...

Make sure pressure does not get too high.

Start with cracks...

Mollers · 13 July 2014, 22:02

Quote:

Originally Posted by ShinyShoe

I've used a 12v car tyre pump connected to hose pipe
. pipe pushed through bung and sealed with plasticine.

Turn on pump. Work round every seam and fitting with soapy water.....

Something like that.

woodski · 14 July 2014, 15:28

Hi Guys thanks for your interest and suggestions and no I dont recall a video of the flooded boat although it has had plenty on our last trip around Coll.

With regard to the bung I replaced the o ring surrounding it and have put a smear of waterproof grease around it.

I suppose the Northcraft builders had seen this as an obvious problem and thats why the drain bung was put in

I will try to flood the deck and seen where the bubbles emerge or where water drains to

Cheers Woodski

willk · 14 July 2014, 19:21

Some of the more obvious leak locations are the bung fitting itself, around the drain sock/s and any other through hull fittings you may have. A loose fitting tape on a tube is another good one - an open inch might allow water to jet into the space BEHIND the tube (maybe around the transom boxes). It takes more than a few divers to introduce 200L of water into a boat.