Any boats manufacturers moving away from aluminum fuel tanks?

flkeys2000

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If plastic/poly seems to be the better alternative for replacement tanks - so I've heard - why are aren't boat builders using them to begin with??
 

BRICH1260

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My Chaparral has a molded tank. It`s kind of nice as you can see the fuel level thru the side panel to double check the gauge.
 

GA_Boater

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The manufacturers don't build any tanks in a boat - Fuel, potable water, gray water, etc. Some tanks may be built to a builders spec, but most are off the shelf and the cheapest supplier wins. Costs to form plastic tanks are higher than aluminum because forms/molds and injection molding equipment are expensive.

Now that doesn't explain why when looking at comparable aluminum tanks and plastic tanks, AL is always more expensive than plastic.

Also - Ethanol does not eat plastic tanks. Plastic tanks in cars and trucks have been the standard for probably 30 years. Where do these ideas come from?
 

oldjeep

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Curious what kind of boat you are seeing aluminum tanks in?
 

flkeys2000

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Never had the luxury of buying a brand new boat, but thought maybe an upgrade ($) like a plastic over aluminum fuel tank might be something offered...

If it was I'd consider targeting those makes/models in the resale marketplace.
 

Scott Danforth

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I believe you are all over thinking it. Cost of a rotational mold for most fuel tanks is usually amortized over the first 100 tanks. average 25 gallon below deck tank in plastic or aluminum will cost the OEM boat company about the same if the volume is about 500 pcs per year or less. above that Plastic will cost less. Is one better than another - not really, they both have equal pros and cons. One doesnt play nice with salt, one doesnt like temperature extremes or UV, both need to be replaced if they are breached. Both must be manufactured in a qualified and certified manor.

Aluminum vs plastic has no resale impact.

low volume models or special tanks can be stainless steel or aluminum because the lead time is shorter and the cost to cover initial capitol of the mold is passed on to the customer.

Many boats such as Cruisers, Carver, Welcraft, Formula, etc. have aluminum tanks. Many boats such as Bayliners, regals, searays, etc have plastic tanks. its not across the board, it is a per model case based on volume (see first paragraph)

per USCG requirements, the fuel system must be inspected periodically regardless of material http://newboatbuilders.com/pages/fuel.html http://www.uscgboating.org/assets/1/AssetManager/ABYC.1002.01.pdf

Ethanol did not play nice with fiberglass tanks
 

shrew

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I've seen old boats with fiberglass tanks. I've seen smaller boats with plastic tanks. I've never seen a large plastic fuel tank. All the boats with 80+ gallons tanks I've seen have aluminum tanks. That includes Bayliners and Searays.
 

oldjeep

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Never seen a tow boat with an aluminum tank, but I think the biggest tank I've heard of in a wake boat is about 88 gallons.
 

frantically relaxing

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Nov 19, 2011
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Our SkipperLiner started taking on water last Fathers day, the result of many small holes in the steel hull, caused by stray current corrosion- which is not to be confused with galvanic corrosion. Stray current corrosion is the result of low DC voltage energizing normally grounded metal in the boat that's in contact with water. (or humidity outside water I'm finding out). And it is particularly destructive. The usual cause is bilge pumps, because if there's water in the bilge, the pump's hot feed will be in the water, and any current leakage will energize whatever the pump is grounded to, such as metal thru-hull fittings and, of course, outdrives.

The reason I bring this up is because I have 3 aluminum fuel tanks and an aluminum black waste tank in the SkipperLiner. The waste tank has a corrosion hole the size of a dime right on top. And my starboard 78 gallon fuel tank has a hole 9" from the bottom, that I've yet to see because it's hidden, but I found out the hardest way that it's indeed there-- And stray current corrosion is the source of both holes...

For this reason, if ever I have a choice of tank material for fuel, water or waste, it will be NOT be aluminum!
 

airshot

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Proper maintenance on an aluminum tank is everything, alum tanks should never be attached to other metal, a wood or other non conductive spacer needs to be used. I have had many boats with alum tanks over a period of many years and not one issue if installed properly. Just my guess here, but it appears yours was not properly installed. Plastic is good if it is a premium quality tank, cheap plastic tanks are a headache and that is where most problems arise....you get what you pay for!
 

dingbat

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Nov 20, 2001
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PERMEATION
Permeation is a natural phenomenon of gasoline in a cross-linked polyethylene fuel tank.
Permeation is the result of gasoline fumes escaping from the fuel tank, not the loss of liquid fuel.
Several precautions need to be addressed when using a cross-linked polyethylene fuel tank:

Fuel (gasoline) vapors settle to the lowest point in the compartment, therefore, a means for removing the fumes is required. See ABYC Standards Section H-2 for specifics.
A covered boat will not allow these fumes to escape, so build up of these fumes is inevitable. Caution should be taken when a boats fuel tank contains fuel and is covered for an extended period of time. A boat cover should never cover the fuel tanks exterior vent fitting(s).
Fuel vapors will migrate to any compartment open to the fuel tank. The smell of fuel vapors does not necessarily mean that there is a leak in the fuel tank, but a closer inspection should be performed.
Fuel vapors may be absorbed by other objects located in compartments where fuel vapor may migrate. Following the above precautions, a cross-linked polyethylene fuel tank will provide years of service.
 
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Skypirate

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"Also - Ethanol does not eat plastic tanks. Plastic tanks in cars and trucks have been the standard for probably 30 years. Where do these ideas come from?"
But we are talking boats, the auto industries have been playing with different compositions for a long time( and some say right on the fuel cap and warranty " no E85), as mentioned about cross linked polyethelens and permeation, some aircraft also had this issue and had to go back to aluminum header tanks.. no disrespect intended in my response, believe me , I wasn't just making this up
 
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JoLin

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A new poly tank shouldn't have any permeation issues. Some of the earlier ones did. My 1999 Chris craft was one- checked over every hose and fitting several times and could never get rid of the odor.

My .02
 
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Mikeopsycho

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When I looked into a new tank for my boat I chose aluminum because :A- I didn't like the manufactures warning that their plastic tanks need to be installed in a vented compartment due to permeation, and B-there wasn't an off the shelf plastic tank that'd fit my space and custom built would have been ridiculously expensive.
 
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