Cruiser stern prone to letting in the rain - is this the Law?

[Seti-Yeti]

I've search the forum for information regarding this issue and only found reference to the fact that they usually do. Fitting a tonneau cover or such will alleviate the problem but is this the right solution?

 

I won't profess to having seem hundreds of boat rear decks in my quest of ownership but I've seen a few and they all (with one notable exception) seem to have the engine hatch fitted into the deck so there is minimal trip hazard. Fine, but the rain can get in, even with an internal labyrinth design for it to sit in, it's lower than the deck surface - once the rain has filled up the labyrinth, in it comes. Sure, you can have drain holes but these get bunged up very quickly.

 

I was wondering if anyone has or has seen a cruiser deck with what you could describe as an open water deck hatch where the hole in the deck has a raised rim/lip upon which the hatch sits over? This creates a labyrinth higher than the surrounding deck surface therefore reducing the opportunity for water ingress. "OH No! I hear, "a trip hazard" - not if the rest of the deck has a raised self draining surface. Uber posh would be teak for instance.

 

( I shall now await the tirade of very good reasons why this is pants... )

[Athy]

I've search the forum for information regarding this issue and only found reference to the fact that they usually do. Fitting a tonneau cover or such will alleviate the problem but is this the right solution?

 

 

Yes, provided that it overlaps the sides and fits well (probably with press-studs), thus making it rainproof.

[Jess--]

usual method is for the hatch to sit in channel which is drained through the side of the hull.

 

in the pic attached you can see the 2 points that my deck drains (there's another 2 on the other side)

[Seti-Yeti]

I can see those, thanks. Do they get clogged with leaf mould and other detritus?

[valrene9600]

I can see those, thanks. Do they get clogged with leaf mould and other detritus?

If they did a poke with a bamboo cane will clear the holes.

[Jess--]

so far they have stayed clear, nothing more than fine dust in them when dry (but water certainly goes through them in rain)

 

it may be helped by there only being about 2mm of clearance around our engine hatch, the channel it sits on looks to be 40mm angle iron arranged like like a V.

 

may be worth noting that they are the only drainage from my back deck (the whole deck sits below gunwale height by about an inch).

 

I do see some older cruiser stern boats where the back deck is made up with boards sat on flat steel supports, they do suffer quite badly with water getting past the deck, my thoughts are.... steel deck with a drained hatch = no problem / wooden deck with no drainage = make sure your bilge pump is reliable

Edited January 3, 2016 by Jess--

[Richard10002]

No problems with our cruiser stern. Need to ensure the drains are clear, but that's a 2 minute job when the engine hatch is open..... very rare that they are blocked.

[peterboat]

pram cover sorted mine out plus warmer in winter and place to store rubbish

[Murflynn]

I had a Liverpool Boat and the hatch frame was a shallow steel channel (about 50mm wide x 20mm deep) that drained into 25mm pipes that were welded into the base of the channel with a small upstand that prevented the channel draining properly, and incorporated a 90 degree radius bend.

 

problems -

if the trim of the boat is not towards the stern then the channel would overflow at the front before the pipe drains worked.

the channels soon collected muck to prevent free draining towards the pipes.

the pipes soon became blocked.

 

I partially cured it by grinding down each pipe upstand to give it more of a chance, but had to clean the channels and pipes often.

Edited January 3, 2016 by Murflynn

[DHutch]

You should be able to arrange the drains so that the majority goes overboard, which is the best option.

 

However its also rare for it to be dead dry under, engine should have its own drip tray, paint should be kept sound, and chargers/inverters in the area is not overly wise.

 

If you regularly lay the boat up for 6months over winter a cover (fitted or well secured tarp) is not at all stupid.

 

 

Daniel

[Rickent]

pram cover sorted mine out plus warmer in winter and place to store rubbish

 

 

 

 

Mine has this plus lino over the boards, so i have a nice dry engine bilge. The crap thats stored at the back is another matter.

[Hairy Animal]

We had a share in a cruiser stern nb for some 15 years so experienced the drainage in all sorts of weather. As with other replies, the drainage consisted of steel channels about 50 x 20 mm all around the hatch opening, which connected to further channels leading out of the side of the boat. The exit holes were about the same size as the channel so they rarely blocked; lots of leaves could restrict them a bit, but they were easy to clean. I was never aware of them failing to clear even the heaviest of rain, but if they had, the water would only have gone into the wet bilges around the engine, where the bilge pump would deal with it. For the record, the deck was some 150 mm below the gunwales so there was the potential for quite a lot of water to build up if it wasn't running away, but I never saw that happen.

[Machpoint005]

No problems with our cruiser stern. Need to ensure the drains are clear, but that's a 2 minute job when the engine hatch is open..... very rare that they are blocked.

 

Same here - a straight stick does it. No leakage problem except in extreme rainfall or when snow melts. I found a tiny puddle next to the engine bearer last week, but now I've put the tonneau cover on, I expect no wet at all to get into the engine 'ole.

[Tony Brooks]

If the rear steps are outside the cabin area, so doing away with the need for a sliding roof hatch, the bottom step has to be drained so as that is usually below then water level the rain will get into the bilge.

 

Like wise much depends upon how well the self draining channels are designed. Mine are very small with upstands where welds are and pipe drains through the uxter plate that are only about 3/8" id. They do clog and will overflow so the answer is "it all depends upon the design but a good design should not to any significant extent".

[nb Innisfree]

I fitted aluminium chequer plate over the deck boards, extended beyond the edge of the board by a few mm and bent over 90° to provide a drip edge, kept engine bay bone dry.

[nigel 2dogs]

I just let the water in and fit a cheap bilge pump

[Murflynn]

I just let the water in and fit a cheap bilge pump

would a medium-priced one work as well?

[Seti-Yeti]

Thanks all for your replies. All very interesting. The channel design seems to work well in the vast majority of cases albeit with the risk of blockage. I still think a raised aperture is the more "boaty" solution but then that's my background colouring my opinion!

 

[Bullfrog]

I've noticed on ours that the rain runs off the roof down the cabin sides and then on to the walkway on top of the gunnel.

 

If the boat is up at the bows (eg low water level in bow tank) then the water will run aft along the gunnel and then drop into the stern well. ie its not just the stern well that has to be drained it's the sum total of all the water that's hitting the boat.

 

That is why in my opinion the drain holes can't cope with the flow when the rain is really heavy.

Edited January 5, 2016 by Bullfrog

[Opener]

I've got a 2003 cruiser stern Pinder shell. The engine access is via two hinged flat steel plates - painted black in the attached (if it works!). There is no lip around the deck and the plates lie flush with the deck area so no trip hazard.

 

When closed the hatches sit on a channel approx. 2 inches wide and 1.5 inches deep which runs right around the engine bay opening. The channel is welded to the edge of the rear deck so any water running off the deck or off the hatch plates will run into the channel. There is a single outflow from this channel at the very rearmost corner and a metal tube/pipe runs downwards (through the engine bay) at 45 degrees exiting the hull maybe 6 inches above the waterline.

 

The hatches are a fairly good fit within the aperture so any passing leaves have to be pretty zealous to get into the channel. I've only had one full blown blockage in around five years of ownership and I'm not on board the whole time to keep an eye on it. 15 mins with a sponge and a bucket soon sorted the minor flood which had not even bothered the bilge pump. Otherwise the engine bay stays dry.

 

So, I'd agree with Set-Yeti. The channel works well with a very limited risk of blockage, a nice flat deck area which manages to look neat and feel secure under foot.

 

[blackrose]

I can see those, thanks. Do they get clogged with leaf mould and other detritus?

Of course, if they are not kept clean. The main cause of water in the engine spaces of well designed cruiser stern boats is the owners failure to keep the drainage channels and pipes clear. It's really not a difficult job to do.

[pig]

A dry engine compartment is a pipe dream for me.

My boat has a silly arrangement where the steps down into the rear cabin are outside the door, so rainwater builds up in the stairwell, or would if there wasn't a drain hole down into the bilge.

I've tried to arrange for this water to go to a container with it's own bilge pump, but then found that water was coming from the deckboards as well, so I'm resigned to having a wet bilge.

[Machpoint005]

Yes, I've often wondered why they build them like that. when we were looking for our present boat I remember viewing at least two where the collected water had caused obvious corrosion. Mind you, even reputable builders are capable of creating water traps in silly places.