Water filled Keel tanks?

[D.Duck44]

Flooding it with water for ballast. Firstly, water is not very heavy, even though it is cheap.

It seems a really crummy, inefficient jerry-built way of going about things, and it has left you with a problem you should not have.
Much better to use steel scrap in a little concrete and get the weight down lower.
However, that was not the main concern of my post. I was more concerned with suggesting a method by which you can measure plate wastage in those areas, so you will not have to open them up.

 

[LeoKa]

I was more concerned with suggesting a method by which you can measure plate wastage in those areas, so you will not have to open them up.

I think your suggestion is valid. For a steel boat it is a good idea to have a thickness gauge. This way I could check the hull myself at every haul out. I will consider it.

The question is; how to go about the tanks? If I find them in bad shape, instead of opening and reviving them, a new set of tanks should be build and welded on. I don't know how much a boatyard would charge for a job like this, but it should be considered. At the same time, I could add more ballast to make the boat low heavy again. If this done at the same time, some money could be saved on labor.

By not having any documentation of this custom built hull, it is hard to make predictions. The job is not urgent and I would not consider this, if it was too expensive. If I can afford it, maybe this is the best way to go. Meaning, remove the old and install two new tanks in the keel.

What if the new tanks are larger? Will this help with the ballast problem? I know that the original built was not perfect and it was aft heavy. The builder had to add an air filled tank to the aft below, to bring the buoyancy back to normal.
It was suggested to hire a marine architect to figure out the proper solution.

 

[senangsekali]

In some large ships. The fuel tanks fill with comp water for ballast as the fuel level drops.

 

[Juggerknot]

I think your suggestion is valid. For a steel boat it is a good idea to have a thickness gauge. This way I could check the hull myself at every haul out. I will consider it.

The question is; how to go about the tanks? If I find them in bad shape, instead of opening and reviving them, a new set of tanks should be build and welded on. I don't know how much a boatyard would charge for a job like this, but it should be considered. At the same time, I could add more ballast to make the boat low heavy again. If this done at the same time, some money could be saved on labor.

By not having any documentation of this custom built hull, it is hard to make predictions. The job is not urgent and I would not consider this, if it was too expensive. If I can afford it, maybe this is the best way to go. Meaning, remove the old and install two new tanks in the keel.

What if the new tanks are larger? Will this help with the ballast problem? I know that the original built was not perfect and it was aft heavy. The builder had to add an air filled tank to the aft below, to bring the buoyancy back to normal.
It was suggested to hire a marine architect to figure out the proper solution.

My thoughts exactly. A competent marine architect should be the first thing. Do you have "as built" plans of the vessel ? Pick the previous owners brain and track down the original owner if possible. Asking questions is a whole lot cheaper than opening up an unknown situation.

 

[LeoKa]

My thoughts exactly. A competent marine architect should be the first thing. Do you have "as built" plans of the vessel ? Pick the previous owners brain and track down the original owner if possible. Asking questions is a whole lot cheaper than opening up an unknown situation.

I am trying to track down the original owner and I seeked out to the architect, who was involved at one point. Not very easy, since I don't have any documentation on the life of the boat. I have old receipts, which can help to find the first owner.

I tend to agree with you. I don't want to open up anything on the bottom, unless it is absolutely necessary.
Some of the opinions have scared me a bit, so it is possible that a new set of tanks on the bottom will be the only safe solution. I am not against it, I just don't know what it will cost? My budget is tight.

 

[Juggerknot]

I am trying to track down the original owner and I seeked out to the architect, who was involved at one point. Not very easy, since I don't have any documentation on the life of the boat. I have old receipts, which can help to find the first owner.

I tend to agree with you. I don't want to open up anything on the bottom, unless it is absolutely necessary.
Some of the opinions have scared me a bit, so it is possible that a new set of tanks on the bottom will be the only safe solution. I am not against it, I just don't know what it will cost? My budget is tight.

It sounds like you are on the right track. Maybe the DMV in your state can provide chain of ownership, also, if she was built nearby, visit the yard, maybe someone involved in the build is still there that may have some answers.
To me, opening up the tanks and adding adequate inspection ports is no issue and not costly, my concern is the fact she was designed as a motor sailer and ballasting could be the reason for the sealed tanks. 5000 lbs is not a lot in terms of lead or concrete if needed so, as long as you have the room, and it's determined essential, you should be good to re-purpose those tanks. Better safe than sorry on something like seaworthyness.

 

[LeoKa]

To me, opening up the tanks and adding adequate inspection ports is no issue and not costly, my concern is the fact she was designed as a motor sailer and ballasting could be the reason for the sealed tanks. 5000 lbs is not a lot in terms of lead or concrete if needed so, as long as you have the room, and it's determined essential, you should be good to re-purpose those tanks. Better safe than sorry on something like seaworthyness.

You are right on point. The reason of the boat's tenderness is not adequate ballast below. The flooded tanks do help, but not enough. I was able to talk to a professional, who was assisting the owner at one point with the suggested correction. His recommendation is the same as yours, just like he has suggested back then. Recommission the tanks back to fuel and add enough ballast to the keel to bring the boat back to normal. This should have been done at the first place. Maybe the money was not there, maybe something else. Either way, this has to be corrected in the future.
I am willing to spend the money, if budget allows, but I want to do it right. As of now, my dilemma is this; do I want to replace the tanks, so the cleaning expense and additional problems to be eliminated? Or, clean the tanks and add ballast? If I replace the tanks, can they be larger, so they could function as the required ballast, besides serving as fuel tanks? Or, this is a wrong idea?

 

[Juggerknot]

You are right on point. The reason of the boat's tenderness is not adequate ballast below. The flooded tanks do help, but not enough. I was able to talk to a professional, who was assisting the owner at one point with the suggested correction. His recommendation is the same as yours, just like he has suggested back then. Recommission the tanks back to fuel and add enough ballast to the keel to bring the boat back to normal. This should have been done at the first place. Maybe the money was not there, maybe something else. Either way, this has to be corrected in the future.
I am willing to spend the money, if budget allows, but I want to do it right. As of now, my dilemma is this; do I want to replace the tanks, so the cleaning expense and additional problems to be eliminated? Or, clean the tanks and add ballast? If I replace the tanks, can they be larger, so they could function as the required ballast, besides serving as fuel tanks? Or, this is a wrong idea?

I am no marine architect so my advice is worth exactly what you're paying for it =)
My opinion is that static permanent and correctly placed ballast is the correct way to make safe your vessel. The professional can not only calculate the amount, the placement but also work within the parameters of the true calculated displacement value of the hull. It is a misnomer that fuel tanks make good ballast since your effective center of gravity would be constantly in flux, moving up as the tank levels went down hence static, permanent lead or concrete ballast. The roll coefficient of the design must be carefully evaluated or you can find yourself in a precarious position, no pun intended. You're getting somewhere by the sounds of it, ask for specifics and the calculations that led the consultant to his conclusions, money well spent IMHO as long as he is a qualified and licensed marine architect.

 

[JohnHayden549]

I have two 400/400 gallons tanks in the keel, which are sealed and flooded with water. It's been like this possibly over a decade. I believe they are steel tanks, since they are part of the keel.
If I wish to revive these tanks and use them again, what would be the cleanup process? Anyone ever had to do this?

I think this is an interesting problem. Your concern is how to reuse the tanks. Since you have full access to them, modification to hold fuel seems like a good idea (to me). I guess you want to clean them enough to use fuel. There is a technique for sealing underground pipes, where some plastic bladder is inserted then expanded (with air) and allowed to harden in that configuration, providing a plastic-lined fuel tank. My concerns is with cost, whether the plastic is suitable for the fuel, and how to do it. Please keep us posted.

 

[LeoKa]

I am no marine architect so my advice is worth exactly what you're paying for it =) You're getting somewhere by the sounds of it, ask for specifics and the calculations that led the consultant to his conclusions, money well spent IMHO as long as he is a qualified and licensed marine architect.

This is where I am at, as well. When time comes, I will hire a professional and calculate the necessary ballast and its placement. It will be lead bricks placed into the bilge, where there is no disturbance. Next to my engine room, there is the master cabin below. I will lift the bed and floor and place the lead there. That is the center of the hull. The Pro will tell me how much is needed.
This is not urgent, but it will be done, before I'd venture out to the big blue.

 

[LeoKa]

My concerns is with cost, whether the plastic is suitable for the fuel, and how to do it. Please keep us posted.

Yes, I know about the bladder solution, but I will not go that direction.
My latest is to build a complex filter system and run it until the fuel is clean. It might require lots of filters and plenty of time, but at one point, the fuel will be cleaned. Including the water and sentiments inside those keel tanks. I've read few stories like this, when a home made polishing/filtering system did the job. It just takes time. Since I have 4 tanks, each 400 gallons, I can play with this cleaning for a while. All tanks will be connected through a manifold, so transferring the fuel back and forth will not be an issue. I have a stand up ER, and enough space down there to make these installation.
The boat will be pulled out soon and I will see first time, how the bottom looks with those tanks. This can give me more clues, if I even want to make an opening on those tanks.

 

[FF]

"My latest is to build a complex filter system and run it until the fuel is clean. It might require lots of filters and plenty of time, but at one point, the fuel will be cleaned."

No need for a complex expensive system, simply pump the diesel into a 50G drum and let it stand for a day or more.

The water will sink, as should most of the dirt , and the clean fuel can be pulled off the the top , crap at the bottom discarded.

Gravity is a boaters friend , a sump built into a fuel tank , that is serviced , will stop 99% of fuel issues ,

Perhaps you have room for a day tank with a sump?

 

[LeoKa]

Perhaps you have room for a day tank with a sump?

I like the idea.
Yes, I have space for a day tank. Where would you put the sump pump?

 

[FF]

"Yes, I have space for a day tank. Where would you put the sump pump?"

A sump is usually best in any tank that carries fuel as water seems to be the biggest hassle.The pump, usually manual is only used to check the fuel in the tank, perhaps weekly.

If a sump were only in the day tank the fuel would be treated and filtered before pumping into the day tank , then only the on engine filter would be required.

As day tanks are usually small (24-30 hours or so ) and mounted high to create gravity feed the sump might be serviced with a plastic cup under a safety valve.

 

[Nomad Willy]

I don’t know if it’s been mentioned yet but for roll reduction/control weight is better placed far outboard like inside the boat and just above where rolling chocks would go on the outside. In other words in the outer bilge and some boats have such ballast right under the deck, again far outboard.
This way the weight is further from the roll axis and has more effect than weight down near CL on top of the keel.

 

[LeoKa]

I don’t know if it’s been mentioned yet but for roll reduction/control weight is better placed far outboard like inside the boat and just above where rolling chocks would go on the outside. In other words in the outer bilge and some boats have such ballast right under the deck, again far outboard.
This way the weight is further from the roll axis and has more effect than weight down near CL on top of the keel.

Interesting point. I thought it was the opposite.
Would you concentrate the weight as much as possible to one spot, or spread it longitudinally?

 

[Nomad Willy]

LeoKa,
Spread it along the side of the boat where the beam is greatest. And if a boat already has too much weight at one end favor the ballast a bit to the other end.
The designer of the Albin 25 says putting the ballast amidships just under the deck and caprail is best for reducing roll. Up near the gunn’el isusually a bit better as the weight goes a bit further from the ctr of rotation.

 

[C lectric]

Just a cranial cramp.

Do you KNOW what the tanks are filled with? Really know? Have you tested.? Did the P.O. actually tell you water?

I suggest you take a sample from one of them and find out.

It's possible , unless you have already done so, that the tanks are oil filled.

Yes, lighter than water but should not cause any corrosion issues. It would take someone some time but used engine and gear oil is a problem for many to dispose of and MAYBE the P.O. collected it over a period of time.

If that's the case then just pumping them out would be possible with no rust or water issues. Of course you must still dispose of it all.

What ever small amount of oil was left would simply mix with the diesel and be burned as long as the filtering is adequate to catch dirt from the oil. Just remove as much as possible to minimize that mixing.

 

[LeoKa]

Just a cranial cramp.

Do you KNOW what the tanks are filled with? Really know? Have you tested.? Did the P.O. actually tell you water?

I have never sampled it, because I don't want to break the seal just yet.
The broker and PO told me about the water flooded tanks. The problem is not urgent, but I want to learn as much as possible about the best option to utilize these tanks again.

 

[LeoKa]

Do you KNOW what the tanks are filled with? Really know? Have you tested.? Did the P.O. actually tell you water?

I was busy cleaning the bottom last month, but I took some photos of the keel tanks. I attach them for entertainment.

 

[BruceK]

Very entertaining until I realized 1 & 2 were upside down, perhaps for Aussie and NZ viewing.

 

[LeoKa]

Very entertaining until I realized 1 & 2 were upside down, perhaps for Aussie and NZ viewing.

Correct. I just don't know how to flip them here. The originals are standing strait.

 

[porman]

That looks like the BYC railway.

 

[LeoKa]

That looks like the BYC railway.

It is.
What do you think about my question? Is it doable?

 

[sunchaser]

LeoKa.

Echoing what some others have mentioned,

If it were me, I'd talk to one of the several competent NAs in the WA - BC corridor. I've spent time on a BR 60 that was completed about 5 years ago, under the eyes of a NA for survey and loan purposes. I've worked with large water ballasting systems on metal boats, where for stability they are purpose built with liquid weight down low.

In one case I'm familiar with a keel extension where about 500 gallons of an antifreeze solution was used, for corrosion protection. As mentioned earlier oil too could be considered for this purpose, but like diesel could lead to an environmental issue you don't want.

Having an exposed drain / fill plug makes sense, but more for the convenience of periodic change of the liquid ballast. Go slow and be methodical on this issue. Our guesses are not worth much, get advice from pros. You don't want to (over) rock the boat on this.

 

[Taras]

Once you empty the tanks of the water and determine the interior to be clean, pump 3 to 4 psi of air into them and see if they hold the air pressure overnight. This will tell you if there is a potential leak.

 

[LeoKa]

where to open the tanks?

I am baaaack....

Over the snowed in days, I was looking around the ER to see, where to access/open the keel tanks? I have taken several photos, but it is not always easy to show the pipes. It seems that I have 3 different pipes coming out of each keel tank.
- the wide ones with easy access
- next to the wide ones, another pipe about 3/8"
- a tiny one further to stern, possibly 1/4"
These all go downward where the tanks are. Completely sealed and rusty. They might not have been opened for over a decade, or longer.
I suspect, the wide pipes are for fuel fill-up. The middle pipes could be for fuel transfer, which did exist sometimes. (see photos of the manifold). I want to reconnect these tanks to the manifold again, so fuel can be transferred to either tank. As of now, I can do that with tanks 1/2, but not with 3/4 the keel tanks. The tiny pipes could be breathers, but I am not sure.
My goal for now is to see what is inside the tanks? On the long run, I want to dispose whatever is inside there.
What I am asking from you is to guide me, which pipe to attack for opening? Once I have access, how can I look inside there without changing anything? As you could see from the previous photos, the tanks are not very deep, but long. Do I need to assemble a pump/hoses structure, to pump out the water (if it is?), or it is better to hire someone to pump it out?
I'll attach photos. Hopefully they will not be upside-down.

 

[Larry M]

...

 

[LeoKa]

...

Larry. How did you fix my photos? I cannot find the solution to this.

 

[Fish53]

Would it still corrode, if it was airtight and full with water?
I don't even know what water is in there? It could be salt water.

If I understand you correctly, you don't recommend to open these tank from below. No inspection hole from the hull?

You can open them from outside perfectly well if you don't mind the expense of welding it back together after. If these are tanks and not concrete ballast as I would have suspected you'll want a good look inside after the time they've gone uninspected. On steel commercial boats I've owned the ballast tanks are opened annually for inspection and cleaning, fuel and freshwater as well.