Need advice - Flat bilge problems (pumping out issues)

[Visarend]

Hi all. I definitely need advice for my very flat bilge multiple issues.

When I built my 36' boat some 30 yrs ago starting from a RPD bare hull, I installed a manual Gusher Titan pump for the motor bilge that is very very flat. It is obviously effective in pumping out large quantities of water (as when a raw water hose exploded some yrs ago), but due to strainer and hose dimensions cannot be placed to the lowest point of the bilge and leaves some 10-15 ltrs of water sloshing around and spraying everywhere.
When overhauling the motor and repainting the bilge, last year, I added a very flat Rule automatic pump that fits under the motor (can be operated: manually/at intervals/automatically with electronic switch at 2,5 cm height of water) https://www.svb24.com/en/rule-lp900d-bilge-pump.html
Still, 2 issues emerged:

1) I had an oil leak before replacing the gearbox, cleaned manually the bilge with specialized products to get rid of the oily film - but the automatic switch stopped functioning. Of course I can take out the small pump and clean it thoroughly - but at this point feel I cannot rely on the pump, because small oil/diesel leaks can always happen, and the only option is switching to manual mode;

2) engine support and hull stiffeners make 7 compartments badly connected and, when the Rule pump leaves only 1/2 inch under the engine, there is still water in the other 6 compartments making the whole install moist and messy.

I dream of a deep bilge (as I have forward of the engine compartment, over the encapsulated keel), but the only (difficult and somewhat risky option in this direction is to open up a 30x25 window under the engine, and stratifying a kind of bulge to make a lower recess. But this could be the very last option, and am not very much tempted. Moreover, it does not solve the problem of the other 6 compartments.

I look very much forward to your advice!

[Sos]

I have a similar situation in our catamaran. I am fitting bilge pumps but they are only for emergency amounts of water ingress. For the remaining it will have to be removed by hand. I use a vacuum Pela oil extractor to get the last bits of water / oil / diesel out. It has a small but long hose that should reach wherever the last bits of water are.

https://dkutenx65dka0.cloudfront.net...l-Oil-Pump.jpg

[BlackHeron]

This thing is great for getting all the water out.

https://www.amazon.com/dp/B07V4G41K4..._GmXCFb6Z9XD3H

Some teething issues with bad instructions (wiring diagram wrong) and a hose connection on the output of the unit needs to be disassembled and re-assembled correctly so it doesn't leak, but it works great for pumping all the water out down to the last tablespoon or so. Way better than any bilge pump at getting the last bit out.

It is slow, 1 liter/minute so it doesn't by any means replace the bilge pumps, but unless there is an emergency the regular bilge pumps get to have a break since it will never need to run.

[tkeithlu]

Diaphram pumps are self priming an can be run dry without damage. That's a possible clue to their use. If you can rig a diaphram pump so it's intake is in a corner where the slosh will occur, running it until the water goes that direction and gets sucked up might solve your problem. The only other solution I can think of is making a sump, as you suggest.

[djousset]

It seems in general there is a level of acceptance for water in the bilge. I am newish to this so please excuse my naivete but shouldn't the bilge generally be dry? I understand that things may happen allowing water in, but wouldn't consistent water in the bilge, even a small amount be a sign of a leak somewhere? I originally assumed a little bit of water was "ok", even normal. After some investigating and repairs my bilge is now bone dry.
(I hope I haven't just jinxed myself)

[tkeithlu]

You're on track, Diane. Water does get in from above, in my case down the engine ventilation during heavy rain, and both engines and pumps do leak. I used to sail with a man whose wooden catamaran was "dry as a bone." I wish my boat was.

[Sos]

I like to hoover my bilges clean

[wholybee]

I'm trying to visualize the situation. Can you drill holes connecting the 7 areas, and then pour filler into 6 of them so the water drains to the 7th? Drill the holes first, then pour filler to the level of the holes.

[BlackHeron]

Water always gets in. Stuffing boxes are designed to drip. Many showers end up leaking or even pumping to bilges by design. Ice boxes drain to bilges. Keel-stepped masts will let water down the inside of the mast even if the boot on the outside is perfect. Water splashes in with heavy rain and weather. You gotta open the companionway to get inside and out and when it is storming water gets in too. Boats aren't houses.

Show me a boat that is totally bone dry inside and I bet it is a marina queen that isn't used very hard or never leaves the slip.

[djousset]

Originally Posted by BlackHeron

Water always gets in. Stuffing boxes are designed to drip. Many showers end up leaking or even pumping to bilges by design. Ice boxes drain to bilges. Keel-stepped masts will let water down the inside of the mast even if the boot on the outside is perfect. Water splashes in with heavy rain and weather. You gotta open the companionway to get inside and out and when it is storming water gets in too. Boats aren't houses.

Show me a boat that is totally bone dry inside and I bet it is a marina queen that isn't used very hard or never leaves the slip.

Excellent points BlackHeron, thanks for sharing. We are no marina queen, nor have I used her very “hard”. And I am fortunate to have excellent bilge access so it’s easy to sponge up any small amount left after the pump cycles. For now I’ll enjoy the dry, smell-free environment because I’m sure my day will come.

[rslifkin]

Ease of keeping bilges dry depends on boat design in some ways. My boat will stay dry as long as it sits in the slip, but as soon as you move, there are stuffing box drips. And in rough conditions, it's not uncommon to collect some bits of spray through the engine room vents. None of it is a lot of water, but it's all enough that the bilges can't be kept bone dry.

[BlackHeron]

The drybilge system I posted about with a link above does a really good job of keeping our bilge fairly dry.

The water ends up in a fairly small sump, about the size of a milk crate. Before we got the system we always had at a very minimum about a half to three-quarters of an inch in there as that is as far down as the whale gusher hand pump will get it. The actual electric pump couldn't get it closer than a couple of inches and then the flush back from the hoses would add another inch or so as soon as it was shut off.

Now it looks like this after a few minutes.

We have an ice box that drains into here, and the stuffing box drips a bit too. I'd rather it drip too much than not enough and score the drive shaft.

[Visarend]

Originally Posted by BlackHeron

The drybilge system I posted about with a link above does a really good job of keeping our bilge fairly dry.

The water ends up in a fairly small sump, about the size of a milk crate. Before we got the system we always had at a very minimum about a half to three-quarters of an inch in there as that is as far down as the whale gusher hand pump will get it. The actual electric pump couldn't get it closer than a couple of inches and then the flush back from the hoses would add another inch or so as soon as it was shut off.

Now it looks like this after a few minutes.

We have an ice box that drains into here, and the stuffing box drips a bit too. I'd rather it drip too much than not enough and score the drive shaft.

Thank you BlackHeron, your suggestion puts me on track for a similar solution, but probably more advanced in sucking the last drops in a very flat bilge:
https://lifeempirically.com/2018/03/...-bilge-system/


I am thinking of installing this DIY system with two sponges: a fixed one under the engine, the other with a long hose to be moved around in the other compartments as needed. Does it sound practical?

[Visarend]

Originally Posted by wholybee

I'm trying to visualize the situation. Can you drill holes connecting the 7 areas, and then pour filler into 6 of them so the water drains to the 7th? Drill the holes first, then pour filler to the level of the holes.

Thank you Wholybee, but the levels are very close, the real problem is the surface of this flat bilge, 1,5 x 1,5 meters!
This is the reason why I'll probably go for the DIY solution posted before, where one of the 2 sponges shall be moved around as needed (installing 7 sponges/suckers would be probably ineffective, when 5 of them suck air instead of water)

[vpbarkley]

Have a look at this:

https://lifeempirically.com/2018/03/...-bilge-system/

There are commercial units also. Search under "arid bilge".