Replacement fuel tank options

[Joe McClure]

I will be replacing my B31 tank soon and have been reviewing some options. At this time it appears no one makes a fiberglass tank. Hightide (Dan) and Allied Bertram (Richard) do not have a mold at this time. It is also estimated at $4000. Kracor or other plastic rotomolding companies do not make large replacement tanks. It will cost $10,000 for the first tank and about $1600 thereafter. Another option is an aluminum tank. I have read there are potential issue with aluminum and ethanol. Apparantly there may be etching and oxidation that may cause premature failure. Another option is to open the tank, clean, grind, sand, pray and recoat with ethanol resistant coatings. There appears to be numerous coating options. US Standard Fuel Tank Sealer, Fire retard Class 1 resins, ...etc. This is a do it yourself option that has insurance issues. The option I am leaning towards is a stainless tank. I have contacted a local welder in VA that will make one using the original as the template for about $1600 in 3/16".

Does anyone have comments on ethanol and aluminum? What life might you expect? What is the suggested wall thickness?

Are there any reasons not to use a stainless tank? What is the suggested tank wall thickness? Thanks, Joe.

[JohnD]

Joe, I don't think there's any easy answer to this question and I'm facing the same thing in my B35.

A while back, on the old board, there was much discussion about Stainless Steel tanks. I think the one thing that stood out was that they were not approved for a charter ( vessel for hire ) boat. Also, I'd have a little concern over spark-hazards. Though that hazard exists with gas in general and can be easily mitigated through routine maintenance and attention to the tank & line systems (something everyone should be doing anyway). Any way there were long discussions of the pros and cons of SS tanks and I took away from that discussion that not every welder/metal shop could make a SS tank correctly for services in a boat.

Aluminum is somewhat of a standby, but suffers ill effects of ethanol but not like our fiberglass tanks. Also, after having replaced our FG tanks once, subsequent Aluminum tank replacements aren't that big of deal. So if you get 10yrs from one that cost $500, you could replace it 10 times before you get to the cost of a new fiberglass one.

So my vote would be for Aluminum unless a very-good local Stainless Steel tank maker was available (don't be the guinea pig).

[Peter]

There are two issues with Al tanks.

First is that the ETH in concentrations above 10% can etch the aluminum. below 10% everyting in the etching department is A.O.K. The real issue is wether you suffer phase separation in your tank in which case the phase puddle on the bottom of the tank is on the order of 84% ethanol.
This is not good for the AL tank, no good for plastic or even most of the newer fiberglass resins either. About the only thing reliable in that case is 300 series stainless steel. But SST, as JohnD pointed out, is not CG approved for charter boats. It is perfectly legal if you don't use your boat for charter, though. Just make sure you go to an experienced shop to have the tank fab'ed.

The second problem with aluminum is that the Ethanol makes the fuel electrically conductive. Therefor you have galvanic corrosion isssues to deal with. Since the aluminum is pretty far down on the nobility scale, you have to be sure to use all aluminum fittings. These are becoming increasingly available, and if you are aware of the situation should not present a huge problem.

Bottom line is that AL is probably a pretty good choice if you are chartering.
Phase separation is the real culprit, and can damage a lot more than just your tank.
If you go AL just keep an eye on the tank for signs of degredation, and plan on future replacements sometime. i.e. don't put a brand new permanent teak deck down over the new tank.
If you are NOT chartering, I personnally like the stainless route. Still, I'd leave plans open to replace the tank with minimal fuss in the future in case you sell the boat to someone who would like to charter.

Lastly ethanol fuels don't like to sit around. Either the ethanol evaporates off, or it can suck up water and phase separate.
Consider how you use your boat. If you usually take short runs, you might consider having a small "Day tank" that has enough cpacity for your short trips, and a separate "Bunker tank" that you only fill when you are going distances. This keeps the fuel from sitting in your tank all season going sour. It also means that you might find your capacities for each individual tank small enough to where inexpensive "Off the shelf production" tanks will do the trick for you. In that case the cost per tank is measured in hundreds of dollars, not thousands.

[Chuck Fulmer]

Joe
I feel that relining the tanks with an ethanol resistant resin is possibly one of our best options. If a marine surveyor checks the fiberglass work in progress, this should that care of the insurance issues and also satisfies a buyer in the future. Insurance in South Florida with a 1969 boat, with new running gear 2002, is impossible any way. The only quote I was able to get was BoatUS at 9% of agree value per year $600 per year in Georgia. I probably am just as well of with liability and lots of praying or towing out of state yearly. Would shut off valves on the vent hose, when not in use, solve the water absorption and phase separation problem? By the way my grandmother was a McClure.

Chuck

[In Memory Walter K]

Chuck-Relining doesn't work as another post on the site has proven again. You're putting off the innevitable and risking your engines. If you're staying with gas, change your tank. This stuff is poison and unless we can get rid of it, theres no simple fix. Walter

[Carl]

$1500.00 in 3/16" SS? Something does not sound correct unless he is a TRUE BUDDY of yours as that will only cover the cost of Materials.

SS may be a great choice if done correctly, get a few more prices then do some comparing ( Materail Grade, Filler Grade, Welding Process, Welder Certification or recommendations from others), cheapest is not always best.

[R Cahoon]

There are correct resin and fiberglass materials to reline with, the same that is used in current gas station, marina and chemical plant tanks.
The most effective way to reline would be to lay up 2 or three layers of the correct materials. I don't have the name of the materials in front of me but they do exsist.
Yes, I know that all said and done relining could or will not save money or time but done right it is final, Aluminum is not!

Keep Smilin

[craig mac]

my fiberglass guy just relined a tank on a 33---the supplies and labor costs approach a new aluminum---not sure which way to go

[Rawleigh]

I have a friend who crews on a 68" Hatteras which has a pinhole in the middle of the bottom of the Mezanine stainless diesel tank!!

[R Cahoon]

Craig
Like I said relining is not money saver and in some cases not practical. But if it can be done and done right it's final with standing Ethanol at any percentage, with Aluminum its a good choise for now but not final.

Keep Smilin

[Ed Curry]

Craig
Any word from Raybo on how that tank is holding up?

[craig mac]

as i understand it--the tank will be put back in a 33 that will be repowered with diesels---so will not be a problem----the tank had to be redone because the gel coat failed.

[TonyNJ]

I spoke to Kevin Horn (forget where he is from, but a well known fiberglass yard in Fla.) yesterday and basically the process to re-glass our tanks should be the most cost effective way to go. He recommended Interplastics Corp ( http://www.interplastic.com/ ) VE8870 promoted resin which conforms to UL 1316 standards for "All Fuels".

From Interplastics website: VE8770 Vinyl Ester Superior Solvent Resistance, High Heat Capability. Our highest heat distortion point (300° F/149° C) vinyl ester with outstanding retention of physicals in high heat exposure. CoREZYN® VE8770 is an excellent choice in solvent exposure and in construction of high heat exposure corrosion resistant laminates. Used for UL 1316 "All Fuels" applications.

The process he described was to open the tank, grind the interior glass, wash it out and lay at least 3oz of fiberglass mat. The cost should be the hourly rate (his is $100/hr) plus the resin / fiberglass. He estimated about 10 - 15 hrs.

If anyone knows any good glass guys in NJ let me know.

I would suggest that WE supply the resin so there are no "suprises" down the road. Also, it might be a good idea to talk to a surveyor to see if he would write a report to document the work as it was being done. I think it would help for both insurance and sales purposes.

Tony

[Bryan Barlow]

I have a 35' Bertram and its a fairly big pain to remove the glass tank. Has anyone explored fuel tank bladders? The internet is full of fuel cell and fuel bladder ads for Marine and Aircraft applications. This option seems like it might be the easiest and maybe the quickest solution. I am interested in inserting a bladder into my existing glass tank with as little cutting of the original glass tank as possible. Has anyone explored this option and can you provide any detail on a company that custom fabricates bladder tanks for fuel, etc? If you do please email me at bbarlow@caratron.com or call 586-285-7700 x 217.

[pfm]

Joe:

My brother just replaced his fuel tank on his 1978 31 Bertram. We located ABI Industries who has a mold for the 31 fuel tank. The tank is made from Isophthallic resin which is resistant to Ethanol. The old 220 gallon tank was very difficult to get out of the boat. It had to be cut up and removed in pieces. You would not believe how well the 220 gallon tank was made. The tank cost about 3K and $800 for shipping. You can reach ABI at 818 780 1594. Please let me know if you would like to discuss this project is further detail.

PFM

[JohnD]

Joe, I too have a B35 and initially looked into buying a 100-200 gal bladder to get me through this year. I don't recall the costs, but found suppliers through google. I think the costs were $1k or more by the time I added in some additional fuel lines and rigging.

On the 35, the tank is pretty easy to get to, its completely exposed when the floor is removed. As for coming out, that I'm not sure of. I had to have the fwd bulkhead replace on mine several years ago and the guy did a fabulous job "stronger than ever before" were his words. Now the though of cutting that out makes me sick to my stomach.

PFM, that price for a FG tank seems reasonable and would be the best way to go. I called the other company advertising tanks (don't want to name names) and they were not interested in the B35 tank unless I brought hem 3-5 people with deposits….not to mention the price was north of $5k.

I don't have a problem with paying a little for design in addition to the labor and materials but $8k for a fg tank seems like lawyer rates to me, screw 'em when you can (UV, present company excluded of course).

br,
JohnD

[babycakes]

Richard Kidd has my original tank which he is making a pould as we speak, so contact Richard at 305-305-9580, Thats where I'm getting my tank out of glass. Good luck Dave Decker

[JohnD]

I called Richard, the tank is for a B31 not a B35

I sending Richard my info and if there's enough interest He'll do a B35 tank and offered to work with the supplier for pricing, but will proabaly be around $5k.

-jd

[andyvou]

I'm new to this board. I have a 1983 26 bertram with a fiberglass tank. I just finished removing the tank and plan to reline. I have a couple of questions. My plan is to recoat the inside with interplastic corp resin (or similar) then further recoat with a layer of a tank liner called POR-15. I wrote to the company that makes por-15 and they said it would adhere to resin, just wash the surface with a special cleaner they make, sand and brush on 2 coats of por-15. My question is why did a previous post talk about adding a layer of fiberglass mat with the new resin? I understand that if the bottom is in bad shape it would need reinforcement but my bottom should be ok. Are they building a new tank within the old tank ?Would you think that cleaning and sanding prior to adding resin would be adequate? I guess it all comes down to the ability of the new resin to adhere to the older polyester resin.
What are your thoughts ?

Andy

[CaptPatrick]

Andy,

The resin is a vinylester and will have good adhesion by itself, but the reason for adding fiberglass mat is to create a tough non-cracking matrix.

Resin by itself cures and becomes brittle, glass like, and is subject to cracking. Much the way gelcoat cracks with age... In your tank, this cracking could lead to flaking off of resin particles and allowing exposure again to the original wall materials.

Granted, the POR-15 over coat will abate that occurrence to a degree, but it would still be wise to add the mat along with the vinylester. The additional time and material cost will not be that much greater.

Anytime a fresh resin is added over an old resin, surface preparation is paramount. In the case of a fuel tank, the surfaces should be first heavily degreased, followed with a good scrubbing of industrial strength detergent and water, pressure cleaned, and then sanded well with a course paper, (nothing finer than 80 grit), vacuumed, and finally wiped down liberally with denatured alcohol.

Best regards, and welcome aboard!

Patrick