## Fuel Tanks

## from the

## Tayana List

I talked to a guy in San Diego today that repairs tanks, fuel mostly but water as well. He is aware of two tank coatings, Ceram-Kote and Plastisol (sp). They are both 2-part coatings with great flexibility. I will know more next week and will send update then but for now. . .

1) Ceram-Kote requires a #80 anchor surface. This would require sandblasting to get to every nook and cranny. Any surfaces missed in preparation would be a problem.

2) Plastisol (sp) can be applied to clean dry surface. No sanding or other difficult prep necessary.

I also asked him about Tom Cagney's MarineTex under pressure method and he agreed that would also work.

Van Anderson October 2000

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There is also an outfit in Rome, NY, called Microseal which produces a sealer material which is used to seal porous castings. In experiments which I did, I found that it would seal tanks with holes as large as 1/16 inch though it is most effective for sealing smaller leaks. Sorry, I don't have their number here but one can get the number from information.

Earl Potter October 2000

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When we purchased Tundra Spirit 3 years ago, the survey said to clean the rust from the fuel tank (bilge located). I decided to pull the tank to clean the whole thing. This is an fairly easy task once the tank is empty. With the tank on the ground it looked good everywhere except the bottom. It had that crusty stuff and when we started scraping, we when right through the bottom. The tank was 14 years old at that point and had not leaked. We were real happy we found the problem.

Anyway, we went with an Aluminum tank and so far so good. We had a sender put into the tank and I sure am glad we did as it is always nice to know at a glance how much fuel we have. In fact if I were to replace the water tanks, I think I would install them there also.

Bryan & Linda Biesanz Tundra Spirit T37 June 2001

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Bill,

When we first thought about tank replacement, we considered using the SS bilge water tank as a diesel fuel tank....but ended up deciding against it.

Though our SS water tank never leaked, it did have some surface corrosion going on and I think it was only a matter of time. The most prominent was towards the aft bottom - deep bilge area. From what I recall when I looked in the tank, it didn't look real bad, though there was some rust showing along the welds. And since our boat is a little over 20 yrs old (#170), I leaned away from using it as a fuel tank. What convinced me even more was what I was finding when reading about using SS for diesel fuel; Nigel Calders book, among others, touches on this topic. He says that though "SS is considered by many to be the ultimate fuel tank material, in fact it can be some kind of fore-aft risers (at least 1/2" tall or so) to get the tank off of the bilge sole. When I took my tank out, there was a bunch of collected dirt/crud/mud etc under the tank. With the risers / added air under tank - it would add better airflow and you can periodically hose out the bilge and keep it clean under the tank....at least this is what I plan to do, and is what I've done on boats past; usually clean/hose out bilge at least few times a year to keep it clean and work the pumps etc.

Dashew, in his 'Offshore Cruising Encyclopedia' book, touches on this topic briefly. He points out that "the sulfur in diesel fuel can combine with moisture in your tanks to create real corrosion problems."......"SS has to be used in heavy gauges for it to last a reasonable length of time."

There was also a real good article in Cruising World on tanks in October 2000. If using SS - they also talk of using 316L or 317L (L=low carbon), in 12 gauge )0.105") or thicker.....SS fuel tanks "may suffer from corrosion, specifically crevice corrosion. That happens when SS is robbed of its supply of oxygen and kept wet, such as in stagnant bilgewater." The article goes on to talk about 'weld decay' or 'carbide precipitation "along each side of the weld if low carbon SS is used, the heat from the welding process drives the chrome ions out of the weld, leaving strips of mild steel along either side of the weld, which will begin to rust." It's been a while since I looked at the inside of our SS tank -- I don't remember if ours was rusted on each side of the weld or just rusted on the weld seems in general.

The article goes on to say that....."the welded seams along 90-degree corners tend to be brittle. Over time they can work-harden, experience fatigue corrosion, and rack."......"SS tanks may be used for fuel, and to be ABYC compliant, they should be cylindrical and not exceed 20 gallons. That's because big rectangular tanks flex more and their welds are subject to more fatigue. Obviously, few SS fuel tanks are ABYC compliant"

Well, I hope there is something in this lengthy email that is helpful to you. I think I have a couple other sources about tanks etc, but these were what I dug up for now. As I mentioned, we seriously considered using the SS tank for fuel also. If it didn't have as much surface corrosion (though it wasn't visibly extremely bad) we probably would have used it. Maybe yours is in better shape than ours was. I think I recall there being an article or two on this topic in the TogNews letter -- conversion of SS tank to fuel etc.

We are going to be doing extended offshore cruising...hopefully for years, so (as you know) we ended up opting for new Vinylester fiberglass fuel tanks. We didn't want to have any question as to the condition of such a vital piece of the boat. Maybe Rich H will throw in his 2 cents, he seems like he would be knowledgeable in this area.

Good luck with your decision....and have fun if you decide to remove the bilge/bow tanks...it's a fun job, especially the bow tank!! Ya, right!:)

Walter SOLTARA T37 #170 August 2001

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I guess I’m lucky. For the time being, I've overhauled my V-berth tank in place and run a recirculation particulate filter system with the dip tube at the very bottom of the tank ....... with plans to add a dewatering filter system to prevent internal corrosion in the near future.

I do plan to relocate the fuel to midships, & initially plan to use steel tanks (?????)

Although Calder (et al) is correct, I believe he ***misses the point entirely*** as the simple and most obvious solution is to continuously recirculate the oil and remove the free water and the 'dissolved' water, .......... then you CAN use iron tankage. In industry (very large: transformers, circuit breakers, regulators, switch gear, steam turbines, arc-quenching, etc. ) there are special absorptive filters that contain starches / hydroxymethylcellulose, etc. to remove the water. In the power generation industry, they use these filters to remove water from the di-electric transformer oils and this allows the use of steel or iron containment instead of stainless for transformers, etc. - a huge savings overall. No water = no corrosion.

Soooo.... water absorption/removal to me is preferable than using expensive or exotic tank materials. Iron tankage can easily be coated externally to prevent surface rust. Besides, you really don’t want water getting into the engine anyway, so if you simply continuously remove it you won’t need to worry about what its doing to the tank. Right now I’m consulting with a company who manufactures such absorptive filters, ..... and will get back to the group with what I dig up for small applications such as boat fuel. Racor offers these types of filters but they don’t have any real emulsified water removal capacity.

Rich Hampel August 2001

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Another comment of support for Walt's analysis. The lovely and elegantly built Tashiba40/Panda40/Baba40 (all built by Ta-Shing to essentially the same design by Bob Perry) has Stainless Steel fuel tanks in the bilge. Virtually every one of them that I have heard of developed severe corrosion and leakage with failure of the tanks. A number of builders use marine aluminum. But the most cautious and, hopefully, longest lasting are likely to be the fiberglass with vinylester. You also have to make sure that the type of resin used in the construction is fully compatible with diesel fuel. Similarly, should you decide to build your fresh water tanks of plywood and fiberglass as per Dan Spurr and Don Casey's suggestions, make sure that you choose a fiberglass resin that is certified as safe for holding drinking water. Many of the resins will leach various toxins for many years, and their long term impact on health is unknown. (But I can't imagine that it would be good!)

Another strategy would be to use the various butyl rubber flexible tanks by Nauta. They are reportedly safe for diesel or for water. I don't know their projected longevity, but they are supposed to be very durable and long-lasting.

regards, Harvey August 2001

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Subject: Fuel Tank

Harvey,

Not true! I have a 1987 built Tashiba 40 with a factory installed "Black Iron fuel tank". All the Tashiba 40's I know have "Black Iron". They also have rust problems with the tank as Tayana owners report. Some of the Tashiba tanks have failed at the 15-year mark. My fuel tank is showing rust on the outside near the bilge in an inaccessible location. I am very interested in how Tayana owners are addressing this crisis project because it is just down the road for me. Unfortunately, TaShing has installed our tank (110 gallons) in the center of the boat under the cabin sole and under the beautiful cabinetry of the galley and port settee. I know one Tashiba 40 owner who sailed back to Taiwan and had TaShing pull the tank and install a SS one. The Cabinetry was all rebuilt as original. Not many of us have the time or luxury to sail back to our manufacturer for alterations.

Has anyone looked into a, "heavy wall close linked polyethylene custom tank" to fit the space available? I'm not talking about the quality of fuel tank sold in the West Marine catalog. There must be fabricators out there who will make a custom, heavy-wall, close linked, polyethylene tank suitable for diesel fuel storage.

We do have stainless steel water tanks, but the stainless is not of the best quality. I do see rust in the area of welds inside the water tanks when I clean them at the beginning of each season.

Rich Cassano S/V Gray Eagle, Tashiba 40, Oyster Bay, NY, USA August 2001

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Rich,

You might want to contact my friend Tom Beard (although you may have already communicated over the Panda/Tashiba bulletin board). Tom had cautioned me about problems with the fuel tanks when he was shopping for a Panda 40 and I checked one of them out on his behalf. He finally bought a different boat, but that definitely had defective leaking tanks. The previous owner had done a poor patch job, as I recall. I can't remember if Tom had his new tanks made of Aluminum or of Stainless. It would definitely be worth contacting him. He is extremely well informed on these issues.

But your friend who sailed back to Taiwan to have his tank changed..... Now that is determination!

I also have wondered about switching to heavy polyethylene tanks, in the event that our bow tank dies. (It would also be an improvement in weight distribution to move the fuel tank into the bilge, and then shift the water tanks to locations under the settees). A number of Tayana 37 owners have removed the bow tanks. But I wonder if the number of tanks with bad leakage is somewhat less with the tanks in the bow, as they are not likely to be sitting in salt water. The other interesting point is that made by Rich. His comment indicates that the tank corrosion is also related to the residual water in the fuel tank, producing corrosion from the inside.

regards, Harvey August 2001

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You might consider an option I used about 5 years ago. I found that my black iron fuel tank located in the bilge had very large rust scabs. I lifted the tank and hung it from the overhead hand rails. I then took a grinder and ground off all the rust, a very messy job indeed! In the process, I actually went through the bottom because the metal had gotten so thin. After grinding off all of the rust, I coated the entire tank with Ospho. I then glassed over the tank with 5 layers (more on the bottom) of glass cloth using West System resin. When this process was complete, I painted the tank. The results have been very satisfactory; no water can get to the outside of the tank so no rust. I was concerned that the glass would break loose when the tank expanded and contracted with filling but this has not been the case. I think the tank will now last the life of the boat.

Gary Schieferdecker S/V Bold Venture T-37 August 2001

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If my present bow tank starts to leak, and before I’m ready to relocate the tanks to midships, I'm ready to cut the top off, epoxy-in a fiberglass liner + new baffles, and close her up again ---- probably no more than a 2-day job. Haven’t had ANY rusting, etc. since I put in a pumped recirculation filter with a water "knock-out pot", and moved the dip tube to very bottom to be sure to suck up any possible separated water. The real problem with the bow tank is that you have to cut it apart to get it out.

Rich Hampel August 2001

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Subject: Fuel Tank

Rich,

Sounds like an option, but if you're gonna cut the top off AND cut the baffles out, then you're probably doing as much if not more cutting than just cutting the tank up itself to remove it from the bow!

-...probably no more than a 2-day job.

Sounds a little optimistic to do all this in two days. Cutting the top AND baffles alone will take a good chunk of time. And then there is glassing in the walls of tank, waiting for it to cure, and then glassing in your baffles (of which you probably need to lay up first and then cut to shape), waiting for them to cure, and then ?glassing-building up a sheet of fiberglass for the top, probably outside of the boat, cutting it to the shape of the tank and then glassing it in place. Then you would cut out the hole in the lid (or do it first, outside the boat) for the inspection plate/fittings (reused from original tank), then drill holes and epoxy in the bolts for the lid (a good chunk of time in itself). If this is kind of what you had in mind, then I guess you would not be rewelding the original top back on. All added up, I would guess this to take longer than 2 days.

If this is your thinking, ?? then you're basically using the old tank, minus the top, as a shell, to build a new tank in.

I guess this would still be a reasonable option, especially if you didn't want, or have to deal with a new tank in another location - which would probably be the bilge, which means that you would then be relocating the water tanks, which then means that....... removing the bow tank leads to more work, which means that your idea sounds like a more reasonable option if you didn't want to get into dealing with the other tanks! Though, if the bow tank was bad and you didn't want to install in another location, I think I would lean more towards cutting the tank out and having another two tanks built to install in same location, side-by-side - so you could get them back into the bow.

My final thoughts would be -- I would guess that on your boat, you wouldn't have to deal with anything related to your bow tank if you are not seeing any signs of any problems, external or internal. I would guess that the most likely place for any problems would be at the external bottom front and sides. When I removed my tank, I found the problems to be at the external front bottom and sides of tank. Due to coagulation of dirt and stuff, which meant the anchor chain water could not flow freely under the tank. Thus creating a kind of compost, causing the pitting/corrosion on the outside of tank. After cutting up the tank, i found the rest of the tank to be in excellent condition. No signs of any problems at all in interior.

Walter Bruj SOLTARA T37 #170 August 2001

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My father had a Grand Banks 42 built in Taiwan with those lovely black iron tanks. They had leaks that the surveyor went directly to. I used the same surveyor recently on a failed survey. We got to talking about Tayana's, Union's, Hans Christian's, etc. His statement to me was that they all develop leaks in the fuel and water tanks. His statement was that both aluminum and stainless were bad in a bilge. His recommendation was plastic or fiberglass. I know that the biggest Grand Banks dealer in FL uses Fiberglass for replacement. And get this - they cut huge holes in the side of the hull and drag the old ones out and put the new ones in. Scary.

After having built a ply and glass dingy, I would be tempted to build them myself. They are easy materials to work with. Good Luck with your new tanks.

John Reynolds August 2001

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I thought I would forward this as it may be of interest to all.

From: Mtdilemma@
Date: Wed, 26 Sep 2001
To: MASEPOXIES
Subject: Are MAS epoxies FDA approved foodsafe? Are they impervious to Fuel (dies..)
John:
Mas Epoxy Resins and Hardeners are formulated using FDA approvable components. This does not mean that our final formula has been FDA approved for direct food contact but it is a pretty safe bet that the formed polymer would be safe for potable water storage etc. Personally, I have epoxy water tanks and the water does not take on any funny taste etc., with exposure to the tank.

Fuels? Gas - definitely not. Diesel is probably OK but I have to do a little testing to confirm this for you. I would be glad to do the work and get back to you with the information. I usually recommend Ameron for fuel and chemical resistant formulas as this is what they do. We are generally considered a structural resin group.

Thanks, Tony

Forwarded by John Reynolds August 2001

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The tank can be repaired with MarineTex. Get some plastic corner protectors from a wallpaper store and cut to the desired length. Mix the MarineTex and butter the plastic angle. Press the buttered angle in the corners inside the tank and cure. It would help if he can pressurize the tank to a few pounds while it is curing. I have used this method and it works well.

Tom Cagney November 2001

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We, too, have a 1986. Our tank was originally in the keel, 90 gal. It "went south" with the other owner apx 3 years ago. He replaced it with a SS 90 gallon, custom tank in the same location. We also don't go thru a lot of fuel....apx 20 gals all last summer on a lake.

We routinely add a biocide available at most marine stores to help with the gunk. I also have thought of rigging up a "recycle" pump and filter system to cycle the fuel from the bottom of the tank thru a fuel filter to try and keep it clean...any inputs from the TOG site?

Mark & Joan s/v Querencia, T37 April 2002

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My T37 has a steel tank in the forepeek. I opened up the inspection hatch the other day when the fuel level was very low. As expected I found a lot of sludge (crap) but no signs of rusting. Has anyone out there cleaned the tank? Advice?

Greg Barnicoat, Stockholm KISH, T-37 PH Nr. 315 September 2002

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Subject: Cleaning fuel tanks

You can clean it out by hand then scrub all the internals with a long handled bronze wire brush. The very best method however is to remove/dispose of all the oil, mechanically remove the 'crud' as best you can, then use high pressure steam to blast the 'crud' and particulate off the walls to the bottom, etc. Then *polish* the new fuel in the partly cleaned tankage to remove any residual particulate.

Polishing is recirculation of the fuel from the tank back to the tank, typically through a 12 volt transfer pump, then through a 10µM or 15µM Filter, thence back to the tank. The relatively high value of µM retention filter will allow a more open flow from the pump due to less internal resistance (differential pressure) which will enable relatively high flows of recirculating oil through the system and the filter. The recirculation total volume would be in the magnitude of 1000 gallons total filtered, although you would only have 50 gallons in the tank.

Since, for example, the 10µM filter typically has a % removal in LOWER retention (i.e. 20% removal a 2µM, 5% at 0,5µM etc.) at each pass through the recirculation system you will get a statistical removal of very small particulate. Consider that if you recirculate the oil 25 or 50 times, then the statistical reduction comes close to 100% of ALL particles, including submicronic particles (including bacteria). Such 10µM or 15µM filters are quite inexpensive - in the range of USD $8.00 for a 2.75" diameter X 10" length filter. The transfer pump that I use is a Walbro 12 volt Fuel Transfer pump from www.belgoes.com (no longer a good link – try http://www.kaydonfiltration.com/ )..... they also sell filters; but, not GOOD filters.

Most broad-based marine services usually have polishing systems mounted on a cart and can do this service dockside.... but they charge a humongous amount of money to do so and usually don’t leave the recirculation system on long enough to get down in to the truly "removal of essentially all particulate" range. You can make such an 'onboard' recirculation system yourself and every time you take on new fuel or if the sea conditions are rough ..... simply turn on the onboard recirculation system to keep the fuel clean. My system sits in one of the bins just aft of the fuel tank and is mounted on one of the mini-bulkheads.

I guess what I'm saying here is that there are professional services that will clean your tank for you and they are quite good. However you can build (probably for less than a single professional dockside polishing) for yourself your own system, and that system can become a permanently mounted on-board process system to prevent FUTURE trouble. There are several websites devoted to fuel polishing (trawlers, etc.) that you can do a web search for info, but from my professional purification background... those websites are selling snake oil. The techniques therein posted are OK but the equipment and most of the products that they pander are worse than inferior.

Glad to hear that you had no rust inside the bottom of the tank. Consider taking a small mirror on a long handle and go in through the limber holes that drain UNDER the external surfaces of the bottom of the tank and inspect the underside of the tank.... as that's where most of the corrosion and rust is usually found.

Rich Hampel September 2002

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Check out "Gas Boy " portable transfer pumps at their web site: www.gasboy.com/

I purchased their 600 series pump (comes either 12 or 24 VDC) and just stuck it in the tank manhole. It's rated for 20 GPM, so I let it run for about 30 minutes and did it 3 times, so I figured I polished my fuel pretty well. It can also be used as an emergency onboard fuel pump for other vessels either giving some fuel or taking on fuel. Cost was about $235 and it comes with a canister filter. Cheap, quick, and best of all, it does a great job.

Chuck "Sirena" September 2002

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For those of you with Perkins 4-108 diesels, what size micron, final fuel filter do you use? 10, 5, 2, or what? I currently use 10-micron but am considering changing to 2-micron.

Doug Coleman September 2002

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The complicated answer is: Industry convention is that prefiltration stages are 5 times as large in retention than the following stage filter. The final stage filtration should be 1/5th (SMALLER) of the diameter of the most critical orifice (or equivalent) in the engine. "One fifth" is historically chosen because particles tend to 'clump' together and 'bridge' .... so that its probable that 2µM particles will block a 10µM orifice (or equivalent).

My Yanmar uses a 2µM as its integral final stage. I prefilter to 2µM so that I never challenge the engine's integral filter with debris. Filter systems should be sized so that ALL filters (pre and final) fail simultaneously - for economy purposes and so that you are not replacing 'uncompleted' filters. The surface area (larger is better) that you choose is just as important as the 'micron rating' ..... although a dirty filter is more efficient than a new filter.

The resinated paper filters commonly used on boats are typically 90-95% efficient in removal at the advertised size rating, translating in 'absolute' terms:.... a paper 2 micrometer filter probably approaches a 10 or 15 micrometer 'Absolute' rating.

IMPORTANT ..... Be very careful with manufacturer's "micron size" ratings..... as they are 'arbitrary' ratings assigned by the filter manufacturer and bear NO relationship to what is the actual retention !!!!! .... as they NEVER state the removal efficiency at the 'size rating' which can be anywhere from 50 to 97%. Stick with the leading 'brand names' (Racor, Fram, Purolator, etc.) and don’t buy CHEAP.

Rich Hampel September 2002

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Ray & al,

I don't know how I'm going to clean my fuel tank except that it's going to be a mess. I have a simple fuel filter with an 80-mesh filter from McMaster-Carr. I'm going to use this and my fuel pump (a KR12-40 from Belgoes - it's their upgraded replacement for the Walbro 68XX series.) to try to get as much of the gunk off the bottom of the tank. I'm going to insert a length of tubing through the dipstick hole and try my luck. The main goal of this operation is to inspect the fuel as it goes through the filter globe and remove enough water and crud so that the fuel won't clog the yard's heaters. If this is the case, they will pump it out for free.

Once the tank is empty I'll probably use some version of the Long Armstrong Method to swab down the inside of the tank.

I'm thinking of replacing the dipstick with a length of tubing with a removable cap. The hydraulic lines from the auto parts store look sturdy enough. When the vacuum gauge on the Racor indicates that the filter is clogging up, I'll switch the pump inlet to the dipstick, go after the stuff in the bottom of the tank and then replace the filter. Someone suggested that I have a few inches cut from the bottom of the tank so that it wouldn't rest in bilge water and coating the tank (it's aluminum and fairly new) with coal tar epoxy. Does anyone have any thoughts on this?

Coleman Blake Traveler T-37 # 328 November 2002

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Hi Coleman,

Cleaning the tanks is on my list this winter too. I was wondering how you are going about it? A lot of paper towels and long arms or what? My arms aren't long enough to reach around the baffles so I'm trying to engineer a way to do it. I ran down the fuel on purpose this summer and will pump the rest out into cans. Then I'll see how far my arms reach once the inspection port is off. Any ideas?

Also, about the recirculation pump. I like the idea and will probably put one in too but I was advised by a friend who is a very knowledgeable mechanical engineer and world cruiser that I should not waste my money because the engine pumps much more fuel than it uses and therefore polishes the fuel just by running the engine. If you have refrigeration and are living aboard cruising it my not be necessary to install a separate polishing system since you will be using the engine many hours a day. On my friends 80-HP Westerbeke, he says he pumps 10 gallons for every gallon burned at cruising speed. He feels this is sufficient to polish the fuel. Combine that with a gauge for the Racor filter and even if your filter gets a little dirty, you know when to change them by the flow meter. If I had dual Racor filters so I could A/B them to clean one off line, like he does, I too would feel comfortable with not having a polishing system. The point I find interesting is how much fuel goes through the fuel return line back to the tank.

Ray Slaninka Red Bank, NJ November 2002

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Frank,
Part of the grit may be the remains of deceased cooties. Making sure only clean fuel goes into the tank is a necessary first step in making sure only clean fuel goes into the engine. We also have a large Baja filter and all the fuel that goes into Traveler will go through it first. West Marine has come up with new design that improves on the Baja. It was one of Practical Sailor's picks of the year. If we didn't already have the Baja I'd get one.

I'm installing a recirculation/polishing system on Traveler. It only requires one valve and a little extra plumbing. I hope to finish the job this weekend and I'll let the list know how it works. This system will allow me to remove the water that will inevitably get into the tank (water always wins) as well as the corrosion products and cooties that develop as a result. As part of this operation, I'm going to clean the tank so we'll get a fresh start.

Coleman Blake Traveler T-37 #328 November 2002

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Joe,

        If the gunk in the bottom of the tank is "gritty", I would be surprised if it was related to algae or bacteria growth. Gritty, granular stuff is usually corrosion products from your tank or the one at the marina or sand that gets carried in with the fuel.

       The only way to reduce these types of things (you can not ever really eliminate them) is to reduce water in the fuel and filter the fuel going into the tank (I would use a big Baja filter funnel, especially if the marina does not adequately filter their fuel at the pump). I always ask when the spin-on filter on the pump was last changed.

       I have not had to clean the tanks on Magic Dragon yet, only having owned it for a year. I will probably sample the tanks this winter to decide if I need to clean them.

       Our last boat had about 1/4" of oily black residue on the bottom of the aluminum tank. I left it there, because it would have been a big PITA to remove and the Racor filter did a good job of removing it slowly. I never had a problem with filters plugging. This was with 20 years of weekend and seasonal use only.

    Frank Timmons       V-42        "Magic Dragon"        Deltaville, VA              November 2002

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Re: decay and rust of iron tanks in bow

One of the contributing factors to degradation of the iron tank in the bow was apparently lack of adequate ventilation and drainage from the anchor locker (and perhaps other sources of leakage from cap rail and stanchions). Tom Beard pointed out that when he took a pressure water hose and flushed from forward to aft, with the water flowing under the bow fuel tank, he washed down a large amount of wood shavings and other accumulated debris. This was apparently left in place under the fuel tank at the time of the original construction of his boat many years earlier. I subsequently did the same flushing on our 1977 boat in about 2000 - some 23 years later - and found a similar pile of crud washed down from under the bow tank. This included wood shavings, steel washers, pieces of paper, etc. As there is no overboard drainage from the anchor locker, the mud and sand with salt water can accumulate leading to corrosion of the iron tank.

At the moment, we appear to have reasonably sound original iron tanks, but we are only riding on hope that it will last another 26 years. I presume that if I keep the water laden sediment out of the bottom of the inside of the tank, and flush the outside, this should minimize corrosion. When the fuel tank was last emptied and the fuel "polished", the report indicated that there was very little evidence of thinning of the walls of the tank, and no flaking of rusted iron.

Regards, Harvey January 2003

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Subject: Fuel tank replacement

I had a NorSea 27 for 15 years. It had an aluminum fuel tank located in the bilge under the engine. It held up fine.

The early NorSea's had aluminum fuel tanks and they frequently failed because the wrong alloy was used. My tank had been replaced with a new tank made from the correct alloy. I am sorry but I don’t remember the names of the alloys, good or bad. The fuel tank on my NorSea was mounted above an intact 3" PBC pipe that allowed water to flow from the aft bilge (under the stuffing box) to the bilge sump right in front of the fuel tank. The tank was glassed in to its top edge.

I have heard that is not a good material because welding causes the steel to loose its corrosion resistant characteristics and pin hole leaks can form along the welds.

John Lewis January 2003

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Harvey,

I have a friend in Germany who has the heating oil for his house in a 1200 gallon plastic tank in his basement. Since the Germans are so regulation minded and his house is not that old, I suspect it is a pretty safe arrangement. His house does not bounce around in the ocean so that might be a reason that plastic is not used very often. I suspect that metal is better from a fire safety standpoint. A tiny fire near a plastic tank could start a real disaster. I know people who have had electrical fires on their boats due to battery failure. It was something that could not have been predicted and was not the fault of bad maintenance. The fire was started by a defective marine deep cycle battery.

NorSea had roto-molded polyethylene water tanks that held up fine.

I am not so sure that putting the weight of the extra fuel tank aft and high is such a hot idea. The most uncomfortable boat I have ever sailed on was a C&C 39 where the owner kept "balancing" his boat by adding heavy stuff to each end. First, he had a big SS weldment made for anchor handling and that made the boat bow heavy, so he added a radar arch. The radar arch made the boat stern heavy so he went to an all chain road and nice heavy windlass. The boat looked balanced at the dock but hobby horsed in any sort of chop. I know it was not a characteristic of the boat's design because another friend had the same model and it sailed like a dream.

John Lewis January 2003

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I think I raised this question once before, but can't recall receiving an opinion - What are the arguments, pro and con of using plastic tanks for either water or for fuel? We have a thick polyethylene water tank in the bilge. It is only about 50 gallons, and I am thinking of adding an additional 50 gallons either under the settee or in the aft lazarette. The advantage of putting it in the lazarette is that I might be able to install it close to the midline, thus not affecting the balance.

I also recall sailing on a number of boats with plastic fuel tanks. What would be the downside of replacing the iron or corroding aluminum tanks with plastic ones?

Harvey January 2003
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Kamaloha has the arrangement you are going to, with a SS fuel tank in the bilge. As far as I can tell it is original. It's always been a Caribbean boat. So far, knock on wood, the SS fuel tank causes no problems. I haven't done anything yet to try to preserve or nurture it. It seems to have enough room on either side for bilgewater to pass.

SS water tanks fill both settees. They seem to be fine too. I like having two separate H2O tanks in case one gets contaminated, and I always have a "halfway empty" alarm that way.

Charlie Freeman January 2003

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The fire safety issue is most striking. I also wonder if an older polyethylene tank might not be more prone to fracture than a comparable age metal tank. I noted that in Dan Spurr's book on Upgrading Cruising Boat he describes a fiberglass and plywood water tank. Presumably one must use a resin that is approved for drinking water.

Your point about fore-aft balance is an interesting one. I guess that there have been quite a few T-37s with both bow fuel tank and all-chain anchoring with all the weight in the bow. How badly does that affect performance, and does it produce a markedly "bow-down" configuration? Everyone seems to agree that it isn't good, and that it is preferable to have the weight low down in the bilge. But has anyone actually calculated the affect on balance and handling?

Harvey January 2003

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Isophthalic polyester resin, I found, is FDA approved. A quick cure of regular polyester is acceptable (raising the temp of the tank to 145 degrees +/- for a couple of hours). There is also a polyester resin that can be used in diesel tanks but not for gas tanks. I was told the ABYC says Stainless tanks for diesel are limited to 30 gal. The ABYC has set several standards for aluminum tanks also. Most of them are designed for long life of the tank IE the type of aluminum, gauge and how it should be mounted.

Joe Sprouse January 2003

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I would try to stay away from using any type of plastic for drinking water. The chemicals (plasticizers) eventually leak into the water and are carcinogenic. Plastic might be a good solution for diesel.

"Captain" Kirk January 2003

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Thanks for everyone’s input so far on my fuel tank replacement projects. I've been doing some research over the weekend and so far marine-grade aluminum seems to be the leading candidate. Apparently there are several grades of highly corrosion resistant alloys. It looks like 5052-H32 is the preferred material.

FYI I've uploaded a document that defines the different grades and their properties to the FTP server on TOG. I also included my initial sketches for tank layout; comments/opinions/suggestions as always are welcome.

files at ftp://tognews.com/Tortuga_T37/NewFueltank/

J. Ware Tortuga T37 #175 January 2003

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I've just recently gone through a similar experience. I pulled the old tank out and found it full of corrosion and abrasion holes. I used it as a template and had new tank made of aluminum to be used as a fuel tank in the bilge well. After weighing all the alternatives, I went with 3/16" 5058 marine-grade aluminum just because there were too many options and each has it's own pluses and minuses. One thing I did do differently that I read about during my research was I applied a 1/4" piece of high density plastic to the bottom of the tank. Doing this is suppose to keep the occasional moisture in the well from being trapped under the tank and acts as an abrasion surface between the tank and the rough fiberglass well. The tank has been in for all of one week so time will have to be the judge as to whether this was a good choice. One thing is for sure the fuel doesn't have to travel near as far to get to the engine, everything that needs to be connected on my boat seems to be at the opposite ends i.e. head forward, holding tank aft - engine aft, fuel tank forward.

J. Ware Tortuga T37 #175 June 2003

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I don't mind share what my new aluminum tank cost especially when you ask so nicely. I purchased it from Florida Marine Tank and, with the exception of the somewhat handmade nature of the inspection plates, I'm very satisfied with it. The cost was $900 which was about $125 more than what I had quoted initially because I choose to upgrade to 3/16" as opposed to the standard 1/8". The tank holds approx 87 gallons and weighed about 100lbs dry. I have FMT actual drawing of the final dimensions but I haven't uploaded it yet. I did upload some pictures and the drawing I provided FMT for the estimate and construction.

files at ftp://tognews.com/Tortuga_T37/NewFueltank/

John Ware June 2003

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Marco,

It can be done. I've never done it on the tanks in the boat, but have tested oil tanks on land (required by environmental reg's in VA). You'd have to block off all of the connections to and from the tank. Because of the unstayed flat surfaces, you need to use a very low testing pressure, 1/2 psig max. Square tanks are not designed for any internal pressure, and will distort easily or even open up like a tunafish can if you put too much pressure on them. If your tanks are glassed in like ours are, if you round out the tank, you'll break the tank loose from the boat. Not good.

Instead of pressure testing, I would open up the tanks, clean them out well, and look for any pitting from the inside (pay attention to the corners and weld seams). If you don't have rust stains coming out from underneath, you probably are OK on external corrosion on the bottom. I would treat the surface rust with Ospho, and repaint. I did this last spring using Pettit "trailercoat" paint. It seems to be holding up well.

The trick to not having your tanks corrode, is to keep water off them on the outside and make sure that any water that gets in is removed promptly. Keep the tanks as full as possible to avoid breathing and condensation.

Frank Timmons V-42 Magic Dragon Deltaville, VA February 2004

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Subject: Leaky fuel and water tanks - need guidance

Kendall,

There is a product called "Proseal" that is used to seal aluminum airplane wings. It's sold by Aircraft Spruce. It may work on other materials besides cast iron (I would check before buying). It's kind of like a silicone or caulk in consistency.

http://www.aircraftspruce.com/catalog/appages/prosealant.php

or here for the brand name stuff...

http://www.aircraftspruce.com/catalog/appages/ps890.php

John Hovan s/v Celtic Dream October 2004

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For what its worth, I just pulled my 95-gallon fuel tank out of the bilge. After 26 years, the bottom of this black iron beast was gone and it had started to leak fuel if I put more than 20 gallons in. It was resting right on top of the ballast with no provisions for drainage or air circulation beneath it, surprising it even lasted that long. I had 2 smaller tanks custom-made out of black iron using the old fittings and inspection plate. The old tank was tapered 3 ways for a snug fit in the keel and it had to be matched with the 2 new tanks. I made a full size pattern on a 4x8 sheet of Masonite and the welder had no problems and everything came out just right. I am on my way back down to the boat to install all this. I will add a layer of Dri-Deck below the tanks and have already multi-coated them with Dura-plate 235 immediately after sandblast. The Dura-Plate 235 is an industrial coating from Sherwin-Williams made for ballast tanks, bilges, offshore platforms etc...and is approved for salt water immersion (if surface is properly prepped and material properly applied). If I get close to another 26 years out of these new tanks, I'll be happy.

Alain Provost Blue Moon T37 # 95 November 2004

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Subject: Leaky fuel and water tanks - need guidance

Outfitting a tired 1979 Tayana 37. Big trouble - discovered leaky bow fuel tank. With apx 12 gallons in tank, engine off sitting overnight, apx 1 tablespoon of fuel weeps out and drains aft into my oil absorb pad. Unable to see tank bottom or sidewalls without tearing apart V-berth. From the collective wisdom of the group, what is the most logical solution? I have not pulled the access port for visual inspection yet.

Also, green wire connection to stainless water tank below cabin sole has come loose, causing tank to drain into bilge. Looks to be either a ground wire of perhaps remnants of an old sensor. Hole is right at bottom of tank, aft end with green wire hanging out. Looks like there is one more "probe" about 1 inch away for the hole. Found green wire with screw attachment and black rubber cover connected. Tank inside is clean and shiny, no rust. Have others had this problem? Is there a way to plug the hole from the outside? Again - need your guidance on what works.

Thanks, Kendall Bailey Dana Pont, CA November 2004

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I wasn't aware that FRP tanks could become permeated by diesel. My tanks are about 12 years old - do you know how long it takes for this saturation to occur? I'll do the rag test later today.

Thanks, Chuck Snyder November 2004

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Chuck,

Yes, FRP tanks (like hulls) can permeate, it all depends on how well they were built and the resin used (polyester being more permeable than vinylester, and vinylester more permeable than epoxy). I'll share a related shaggy dog story about my own boat:

I hadn't known the stainless steel fuel tank in the saloon/galley bilge was leaking until I had the boat hauled for the winter, and had the hull bottom soda blasted. My boat was 18 years old at the time and had had a vinylester blister repair job done by Osprey Marine Composites (Deale, MD) three years earlier. When the repair work was done, Osprey was still using copper dust in the final vinylester barrier coat. It was supposed to facilitate a hotter cure and a harder (and less permeable) barrier coat.

After the blister repair work, however, I had major problems with flaking bottom paint (I was using Micron CSC ablative paint at the time). The bottom paint would come through the boating season in good shape with little or no fouling. It would also withstand power washing on haulout without flaking. But after sitting on the hard through the winter, the bottom paint would "shatter" like a car's broken windshield and come off in large areas when I tried to roll on a fresh coat of paint.

I'll never know whether the flaking paint problem was due to the paint itself, Osprey's final preparations prior to painting the hull bottom after the repair work, the copper dust in the barrier coat, or a combination of all three. In any event, Osprey no longer uses copper dust or Micron CSC (mine was not the only boat to experience this problem). Osprey's owner, Garry Williams, offered to remove (gratis) all of the bottom paint on the next haulout by soda blasting, in lieu of sanding or scraping, to avoid damaging the barrier coat.

When I inspected the hull bottom after the soda blasting, I noticed several dime to quarter-sized spots, generally in a line corresponding to the top of the keel's ballast cavity. There was a small drop of diesel fuel visible in the center of each spot. After I pumped the contents of Aeolus' fuel tank into a couple of barrels, the hull spots vanished. When I pulled the tank out of the boat, I found a pinhole leak in the bottom. Ta Yang had installed the tank so that it rested directly on the fiberglass laid in keel molding above the ballast. Time, moisture and/or humidity, and sawdust trapped in several areas beneath the tank, combined to produce the pinhole. The FRP laminate had effectively become part of the tank. There was no noticeable fuel or fuel odor in the bilge. But fuel eventually permeated the hull and its barrier coat. In my survey work I've seen several examples of FRP tank or hull permeation. The worst involved engine oil in the bilge.

Do you know who constructed the tanks in your boat and how they were built?

Sue Canfield Aeolus T37 #-305 Annapolis, MD November 2004

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Regis,

You listed many good tips. When I started cleaning the interior of my 25+ year Tayana I took a hose right in with me and cleaned the inside of the hull and was amazed at all the junk, dirt, and debris that ended up in the bilge. I scrubbed every inch that I could reach with a hospital grade disinfectant cleaner that works on gram - and gram + bacteria, mold, etc. (Johnson Virex 256) and it helped out tremendously.

Subsequently, I removed the diesel fuel tank from the bow and the fresh water tank in the bilge and still found saw dust, old screws, bits of wood, coins, etc. that were lodged underneath. I have literally touched every inch of the boat in cleaning it.

I removed all the old hoses, etc., and they reeked of odor. I agree that the biggest contributor to odors is old fuel and sanitation hoses. Once old hoses are replaced and the interior is really cleaned and kept clean on a regular basis, odors should be minimal.

John Keefe CT37 No.63 ODYSSEA Youngstown, NY November 2004

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Subject: T-37 bow fuel tank

I would think that weight in this tank would encourage hobby-horsing, (we’ve never sailed the boat). The prospect of cutting it out and putting a new one in the bilge is not that exciting. Is this one of those “you really should do that when you have her torn up” jobs or is it “not that important to move it”. I did look at the pictures of one tank being cut out and quite frankly…..ugh!

Bill & Sue Jaine T-37 Wellantanzerin Port Hope, Canada June 2005

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There is no question that any tendency to hobby horse is increased by a full tank in the bow - but just how bad is it? After all, lots of T-37's have sailed around the world with bow tanks. The T-37's displacement is on your side when it comes to maintaining forward momentum - unlike those lighter boats.

I would put it in the category of "do when already torn up for other projects" - the other reason for replacing it is if the old tank goes bad - in that case you can decide whether or not you want to replace it with tank(s) in the bilge or a new or repaired tank in the bow. My 1984 T-37 still has the original tank and it is in fairly good condition. The previous owner epoxied the top to retard some rust that was starting there.

I emptied the tank out, removed the inspection plate and had someone come do a through cleaning of the inside with chemicals and brushes. When the cleaning was done, we could see that the tank was in good shape on the inside.

Steve Wolfer s/v Island Girl June 2005

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As has been pointed out many times, a 90-gallon fuel tank in the bow is just not a good place for potentially an extra 600 lbs of weight, especially when you consider the weight of anchors and chain already in the bow. But that's where it is on most T-37s. The question of whether or not to remove the bow tank and when to remove it, in my opinion, depends on the shape it is in. If it is rusty and flaking thin sheets of rusty metal, best to remove it now before a leak develops and dumps a load of diesel into your bilge and then overboard when the bilge pump activates. If the tank appears to be in good shape, maybe you want to leave it alone for now; but ultimately it will need replacing. At the very least, make sure the limber hole just forward of the tank bottom and just aft of the anchor locker is free of gunk and mud so that seawater from your rode drains past the forward bottom of the tank rather than becoming dammed up there by the gunk. And, remove the inspection plate and take a good look into the tank. BTW, my 1984 T-37 still has the original bow fuel tank.

Jim Smiley June 2005

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The positive aspects of a bow fuel tank: there is nothing that says you MUST load a bow tank to capacity. If you start full, when the tank empties you will have less plunging action. You cant store extraneous & needless heavy junk in the bow fuel tank. Downwind the extra bow weight is a good thing to help balance the helm (if you are sailing). If the black iron tank begins to leak, you can epoxy-in a new liner. If you regularly remove the tank water, you won’t need an epoxy liner, new tank, etc. It will 'work' until you move it to near the boat's center of rotation --- later.

Regards, Rich Hampel June 2005

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I cut mine out 2-years ago. It is noisy, nasty, uncomfortable, and your whole body hurts after have wrestled with a grinder and a reciprocating saw. The good news is that it doesn’t take very long. If you start Saturday morning, you'll be done in time for dinner on Sunday.

But make sure you wear a respirator and cover everything in the forward berth with plastic (its dirty work).

S/V Radiance June 2005

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Subject: Diesel smells

I'd like to expand the topic to include diesel smell. Soleil is a V-42 with three black iron tanks. None of the tanks appear to be leaking and all have copper lines to the engine room where short (6") lengths of hose connect them to the distribution valves.

The bilge has been scrubbed to hospital standards and all appropriate treasures have been recovered. Still the diesel smell is noticeable (significant per my other half). I tried a small fan vented outside and running continuously in the engine room, without much luck. Any ideas?

Christine and Ray s/v Soleil V-42 CC #71 June 2005

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The most likely cause for a diesel smell may be the fuel fill hose. I had to replace one of my diesel fuel tank hoses due to an unfavorable method of hose installation. If a hose runs vertically to a tank, it only contains diesel while filling. Or in some cases, while sailing. I have never filled my tanks so full that diesel remains standing in the fill hoses. That's asking for trouble! But my port tank under the settee has a hose that attaches horizontally to a ninety degree pipe on the top of the tank. The problem was that it was not a downhill run all the way. Diesel pooled in the hose near the tank. After 18 years, there was a significant bulge in the hose as the diesel had separated the layers of the hose. It was easy to see the problem. Repositioning during hose replacement solved the geometry problem. Also, if a tank is designed to have the fill hose enter the side of the tank rather than a 90-degree fitting on top, then that tank should never remain filled to that level for a long time.

Wayne V-42 C/C RESTLESS June 2005

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It has finally come around to the fuel tank removal project. I am trying to remove the aft starboard side fuel tank with little success.

I have cut the top off the tank leaving the baffle and lifting ring and attaching a come-along to a 2x4. I have already broken one 2x4 and now have two 2x4s screwed together. The tank is not budging. Nothing appears to be attached to the tank. I only need to raise the tank a few inches or so to miss the hull while cutting.

Does anyone know if Tayana attached tanks to the structure unseen? I have already removed the bilge water tank so this is not a new experience.

Don T-37 #21 October 2005

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Harvey and Tad,

I just removed my tank also and I am very glad I did. It was just a matter of time before I had a bilge full of diesel. Our boat, Hull #118, has been in the TOG news long ago. In fact, Frank & Dottie Stulen (see TOGnews #10) were the first owners (I believe) and kept the boat in the Virgin Islands. Sometime during the 90's, the tank was fixed the first time. Someone painted the inside of the tank with epoxy. When we finally got the tank out of "the hole" there was epoxy that had dripped out the bottom of the tank. So the tank must have leaked quite a bit. How many surveyors look under the tank....they can't, and you can't!! If you have an old boat, I would seriously consider checking your tank. Ours leaked on the port side along the top seam forward and, like some posts talk about, we also had a pile of nasty stuff right below the chain locker that forced the water up and around the fuel tank. You cannot get at this stuff. Like Harvey said you might be able to run water down the sides but believe me there will still be tons of stuff left. YOU WILL NOT BELIEVE WHAT YOU WILL FIND!!! We even found what was left of a can, maybe tuna, maybe something else. My wife, who has a much better nose than I, wouldn't even give it the sniff test. Smart girl!!! Now I feel I have to pull the water tank. I have watched the water stand in front of the water tank and hoped it would go down as one would look in a toilet and wish the same thing!! So now all we have to do is get the smell out of the cushions. There is nothing like a dwindling list. Yea right !!!!

Nick &amp; Julie DeRocher S/V Paul Martin T-37 Hull#118 November 2005

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Bert at www.seafabtanks.com is building us a new custom 100-gallon bilge tank now. We should pick it up sometime next month, I'll let you know how it works out.

Jim Grant T-37 # 370 February 2006

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Jim,

How does the 100-gallon tank fit into the bilge? I'd consider this option instead of the 2 smaller tanks currently in the bilge. The two smaller tanks are placed in between the 2 removable "floorboards" and the teak grate (at the bottom of the companionway). The tanks extend from just in front of the engine to about 18" in behind the compression post. Would the retro-fit of a 100-gallon tank require a bit of sole removal and woodworking?

Steve Abel SV Victoria Rose Tayana 37 #384 February 2006
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Bert at Sea Fab seems very nice and I'm looking forward to getting my tank. With reference to how it fits in the space, I'd have to see your sole. I think mine is pretty standard. You open the two first floor boards and there's the tank. My wife has all the dimensions. If mine fits after Bert builds it, I'm sure everyone could use the drawings we sent him.

Jim Grant February 2006

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Harvey and all,

Considering the limited options on a T37, I think Traveler has a pretty sensible arrangement of tankage. We carry 150 gallons of water in two (factory original) 75-gallon SS tanks, one each located under the port and starboard settees in the main cabin. Our 90-gallon fuel tank is, alas, in the bilge (but for that matter so is the wiring at the base of the keel-stepped mast). Potential exposure to salt water aside, it is low and on the centerline between the galley and nav station. So, additional weight ~ 1200lbs. for full water tanks is centered longitudinally; fuel weight is low as it'll go, and we have no iron fuel tank in the bow, so hobbyhorse special effects are minimized.

I agree with Tad - the old saw about putting all one's eggs in a single basket is particularly true when considering the storage options for potable water offshore ------ watermakers, et. al.,not withstanding.

SandraBlake T-37 Traveler Hull#328 Herndon, VA February 2006

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Jim,
I made contact with Bert at SeafabtankS.com and he was very helpful. After much sucking of teeth, he came up with a price of $1431 per tank, with a 10% discount if I replace the 2 (port & starboard) at the same time. I think that this price, albeit steep, is representative of replacing the tanks with stainless and it should be a once only job (although even the Taiwanese SS lasted 24 yrs!). Thanks for your help, and if anyone else has the same under-bunk arrangement and wants to retain 2 separate 70-gallon tanks, I'm happy to act as an intermediary to see if we can drive the price down.

Stephen February 2006
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This has been a hot topic since the first bow tank was installed on a T-37. I have sailed both in the lumpy seas of Monterey, CA and really didn't notice the difference. While it is probably true that weight in the bow will affect performance, I think the T-37 is less susceptible to hobby horsing and pounding than many other boats. The original reason for moving the tank forward was to give more space under both settees, for battery or other system installation. Moving the steel tank up forward helped keep it out of a salt water environment. I have seen older T-37 and Panda 40 with the fuel tank located centerline in the bilge (where a S.S. water tank is normally located), and after a few salt water baths, like flooding the head or leaking packing gland caused some serious rusting.

Neil Wineberg February 2006

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With respect to the heavy weight of a full forward/bow tank ..... there is no rule that states that the tank must be full. A half empty forward/bow tank can’t be crammed full of heavy stores; hence, a partly full tank keeps the bow light. With saddle tanks amidship, unless you plan to keep them always topped off ...... in my mind its better off to store 'heavy' items in that location. As always, there's two ways of looking at something. My boat hobby-horses a lot less with less than a half empty bow fuel tank.... but then again, I always keep a full 100 gallons of water in the bilge tank... as I perceive the 'top heavy' T-37 rolls more than pitches and high weight well down is the best remedy for that.

Rich Hampel February 2006

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Hi David,

The CAD drawings of the water and fuel tanks in John Lewis's boat can be found at:

http://tognews.com/ftpfiles/Active_Transport/drawings%20of%20tanks%20in%20T37%20581/
However, there may be enough variation in the construction of these boats, that you should double check to be certain that these dimensions apply to your boat as well.

regards, Harvey March 2006

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On this subject, I have heard that West System suggests a method of coating the interior and merely uses the old tank for shape. While I have not checked this out, the source said that West Systems gave detailed instructions (using their products of course) and the favorable end result was done with tanks in place. If true, this might save a lot of time and $$ on this issue. You may wish to contact them to see if my source is correct.

David sv hegira April 2006
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WEST SYSTEM is probably a good time and money economical method of refurbishing/relining a fuel tank. However, WEST does not have a material that is FDA approved for potable water. For potable water tank linings, go to Interlux Marine Division and see (or do web search) for their product "Interline, 925" .... suitable for lining potable water tanks.

Rich Hampel Ty37 #423 "Aquila April 2006

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Harvey's multiple tank idea makes me think that if I replace the 90-gallon fuel tank in the bilge, I should install two independent tanks - each with its own RACOR filter, using only one for weekend sailing and then leave the other unused until we start cruising....
Dom Sheehan S/V Timimoune Hull #520 March 2006
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