Fuel Tanks

Important note: The information here is not warranted. Each writer has contributed his or her own opinions and experience for the benefit of other Nor'Sea owners and does so with the caveat that should you have difficulties implementing these suggestions or as a result of using them, the writer accepts no blame nor offers any warranty or redress. Please proceed at your own risk.

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In Praise of Diesel

I love the smell of diesel fuel in the morning or, better yet, on the midnight-to-four watch. Who can forget the silky feel of this aromatic liquid as it trickles into the armpit and thence into the just-cleaned bilge? Or the rainbows formed in the fine mist created by bleeding the system underway? These memories make me long to change filters right now!

I have carried this previous fluid in jerry jugs all over the world. Despite reverential caution, I have spilled it on new teak decks, freshly-scrubbed cockpit grates, and, for an unforgettable entertainment, in Mexican taxis. A mere teaspoon of diesel mixed with rain water in the bottom of a rubber dinghy will render it silky, slippery, and fragrant for weeks.

This most noble of liquids has provided endless respite from the boredom of cruising. The search for it takes us to paradise's most interesting places where tourists never go (those who dispense diesel are the very essence of local color). Carefully-chosen jerry jugs provide a splash of color on a drab side deck and give lifelines a reason for being. You can tell an upscale anchorage if the jugs have matching canvas covers.

God tends to create balances. Those endless white sand Caribbean beaches are uncrowded, thanks to voracious sand fleas. Cheap rum causes blinding headaches. For every downwind, there is a windward. For the yachtie, blessed with being one of God's most perfect creatures, He created diesel fuel.

A Couple of Gimmicks to Make Dealing with It Easier

Parallel fuel filters. A few hose tees, a fuel valve, and an additional fuel filter will gain you immeasurable peace of mind. If you have two filters in parallel, you can: (1) instantly switch to the other if one filter gets plugged; (2) change a fuel filter underway with engine running; (3) instantly bypass an airlock in a filter.

Squeeze bulb. Changing filters or bleeding the system is made immeasurably easier by installing an outboard fuel tank squeeze bulb in the fuel line between the tank and the first fuel filter (I trust you have a pre-filter in addition to the one on the engine.) Changing filters? Just squeeze until the new filter is full and bleeds clear. Bleeding the system? Just squeeze and bleed and forget that effete little tickler on the fuel pump. With this system, you can have the engine bled and running within a minute after changing filters.

Additionally, in an emergency, you can quickly force fuel through a mysterious airlock, and should the engine-driven fuel pump foul, you can station a crew person below to give the bulb a squeeze occasionally to get your home. If you carry an extra length of hose, you could jury-rig to squeeze from the cockpit.

A couple of caveats: (1) Don't create a new airlock! Choose a high-quality bulb. Exchange the cheap clamps supplied with all-stainless and goop the joints with silicone. Replace every few years. (2) Install it in proper direction. For years I used an electric fuel pump in the same location for the same purpose. When I went to replace it, I couldn't find one with a decent cleanable internal filter. (Remember: if you have a thank full of crud, the first thing it will plug will be the electric pump.)

Now, when is the last time you heard of a great marine improvement or marine anything for under $10?

How many times have you struggled with a boat problem while muttering, "I wish that %#*@! Designer could be here right now!"? Well, folks, I've been there! On my knees with my head in the engine compartment. My wife, Jacqueline, has been there, too. She's small enough to crawl entirely in.

Some background: we chose to put the Nor'Sea fuel tank in the keel. It used unusable space and provided ballast. To fill that awkward space, we designed a very complex-shaped tank. It was made of an aluminum alloy which was "guaranteed not to corrode in any marine environment." We then encapsulated it in closed-cell foam which was "impervious to saline and aromatic liquids." Right! After 15 years and 40,000 miles, our tanks' aluminum was Swiss cheese and the closed-cell foam was a sponge.

If you're in this vast majority and your fuel tank is not now leaking, you *must* preserve it by preventing saltwater from reaching it. Saltwater reaches the tank from two sources. Foremost is the shaft packing gland. Here it is necessary to build a waterproof dam connected to a drain hose going over the tank and into the sump. Second is the sump itself. Fiberglas covers the tank about two-thirds of the way up, but a full bilge can reach the tank. The seal must be extended to the top of the tank.

If you do have a leaky tank, you can (1) ignore it; use water absorbers and biocide; (2) re-seal the tank internally with some magic goop; results unknown; (3) seal the tank externally; (4) replace the rank with a rubber bladder type; (5) replace the aluminum tank.

Choice #1 has a catch 22: if diesel leaks out, water leaks in. Biological sludge grows in the interface of water and fuel, and chances are if you have a leaking tank you have sludge in the tank. It will lurk there quietly until you have to make harbor to windward on a wild night. The wild motion will stir it up to plug your filters; the fuel pressure will be the reciprocal of your blood pressure. The fix here is to clean out the tank and keep your fuel laced with water absorbers and biocides.

I chose #3. I sealed the entire tank with cloth and epoxy and sealed both the main sump and the shaft log area with epoxy. This prevents diesel from leaking and water from intruding. Now the keel becomes the fuel tank. Nor'Seas were laid up with isopthalce resins. This is the construction which has been used on Hatteras and Bertram fuel tanks for years. Four years later, I have seen no problems.

Ed and Ellen Zacko (#44) chose fix #5 and replaced their aluminum tank. Ed has written a tome on how it's done, but don't bother him with a request unless you are prepared to spend hundreds of hours and/or thousands of dollars. This is *no* easy task. Ed is blase about it now, but I didn't talk to him during the job!

If you choose to thoroughly clean out your tank, it requires two inspection plates covering large cleanout holes. If you're lucky, there is a local fuel cleaning service to do the clean out. If not, I suggest you take your boat to where there is one. You will save a lot of aggravation and give you a nice cruise.

Ed also had some suggestions for fabricating and installing inspection plates. There is a baffle midway on the tank. It may or may not be necessary to remove the engine to install the inspection plates. Don't be intimidated by this. A good yard should be able to remove the engine in 1.5 to 3 hours. I have it by myself at sea in a few hours. Be sure the yard has a "C frame" hoist and is familiar with sailboats/ This will also give you a chance to clean out the bilge and engine, repaint where necessary, and give things a good look over-like checking the brushes on the starter if you have 1000+ hours.

A caveat: if possible, remove the engine without pulling the lag bolts holding the engine mounts to the wooden engine bed. Polyester resin was poured into the lag bolt holes to prevent vibration from eventually loosening the wood surrounding the lag bolts. If you must remove them, rock the lag bolts back and forth and hammer them viciously to break them free. Just pulling on them harder with a bigger wrench may snap them off.

Also, *always* use a biocide and water absorbers and relax! Relax is *after* you have installed the dam and hose to divert shaft log drip water over the tank and sealed the front of the tank adjacent to the bilge sump.

In some of the boats built between 1976 sand 1980, the tank is flame-welded with welding rod and an oxacet torch. The problem is the welding rod is dissimilar metal to the tank sheet metal; and any time you have an alkaline solution (saltwater) and two dissimilar metals, you have a battery. Keep it dry, folks! Tanks from these years sometimes corrode at the seams for this reason. In the 1980s, I changed the welding process to TIG (tungsten inert gas). This produces an absolutely beautiful clean and shiny weld. The metal we use is called 5052 (aircraft quality aluminum). We always have a couple in stock should you need one. (714-489-8227)

• Magic goo inside tank. I was strongly advised against this approach by Yanmar and also by the company that makes the sealer. It works well on jet planes, but in the marine environment, it is iffy.
• Encapsulating the tank (Dean's solution). This is probably a good idea, but I was afraid that the diesel fuel would act on the old foam in such a way that the foam would end up in the injectors.
• Bladder tank. I've known too many cruisers who have had them leak and rupture at the wrong time. I don't trust them.
• Replacement. It seemed that this was the only permanent fix that we could trust to real ocean cruise. I was actually going to try to repair my tank, even though I was admonished by a German engine mechanic: "If you have one leak, you have a thousand little ones. I guarantee it! Remove the tank and replace it." He was right on! Dean is right about two things, though: I would not want to pay a boatyard to do this job. It's not at all difficult; it just takes some time. The results are worth it. You should be able to do the entire job in less than two weeks.
• Remove the old tank and replace it. I always said I'd take this option, but in the end discarded it. I was thinking I would remove the old tank and replace it with some sort of water tank under the engine and remove the port water tank and replace it with an aluminum fuel tank. This would result in 10 gallons more water and 10 gallons less fuel, plus the trim of the boat improves and the fuel pump problems disappear. You do, however, run the risk of fuel smell in the cabin. I just chickened out. Now with the desalinator, we don't need the extra water, but I'm glad for the fuel.

So I put in through-hulls but I didn't feel very good about it either legally or morally. Then, for various reasons, the boat was out of the water for 10 years and during that time I had what I thought was a brilliant plan - - SWITCH THE TANKS! A thirty-gallon holding tank would be a better "live-aboard" size and a smaller fuel tank, conforming somewhat to the shape of the hull, could take the place of that blue lunch box-sized head tank and its pedestal on the port side of the engine room.

So last year I got everything fabricated, re-arranged, back together, and in the water (we live in Massachussetts). And everything worked great. And worked great again this year, too. The new tank has a clear plastic tube that runs along the side of the tank from the top to the bottomm functioning as a fuel gage during the season and a siphon during storage. And since the tank slides into position and bolts to the bulkhead and engine bed, it can easily be removed for cleaning or replacement without removing the engine. Also, the tank holds 9 gal.- - which is about 50 hours of motoring. All my problems solved. No worries. Right?

Now I read that getting salt water on the aluminum tank under the engine is a disaster - - particularly for boats of my vintage. And here I've been pumping salt water -into- the tank for two years. At least I don't have fuel worries.

But I don't want the contents of that tank leaking out since it is now a holding tank. I suppose I could encapsulate the tank as Dean Wixom suggested. If I do that, will I have osmotic blisters inside the keel? Does anyone have any sage advice here? You know, the keel holding tank idea (made of plastic) should have been an option from the start.