Pulling fuel tank advice needed

[jerryjerry05]

Re: Fuel tank out - should I paint it?

Re: Fuel tank out - should I paint it?

Do a SERIOUS inspection.
ANY corrosion at all and the tanks gonna gonna rot through.
1 spot and it should be replaced.
If there isin't any?? Then clean it good and put it back.
The Rhino lining stuff is a good bet.But not necessary.
Painting's not needed.
Or replace with a similar plastic tank.

 

[greenbush future]

Re: Fuel tank out - should I paint it?

Re: Fuel tank out - should I paint it?

I've often wondered if all the work I see many DIY's do with tanks that come out of older boats is really worth the effort. Some of these guys are spending quite a bit of time and $$ to make these things look like a new car, only to bury them under the deck never to be seen again. After reading the tank expert that Fireman posted, it looks like all this work may not really be worth it? I can see value in patching up a tank that is pitting, and doing a pressure test to avoid a failure, but it looks as though the experts are saying don't bother with the fancy prime and paint??

 

[film842]

Re: Fuel tank out - should I paint it?

Re: Fuel tank out - should I paint it?

Thanks everybody for the advice. I'm going to to go with the majority and not cover it. I also won't be foaming it in...it's in there pretty tight as is so I'll just lay new rubber strips for it to lay on, put it back in and rebuild the forward bulkhead around it. Although it's snug in there it looked to me like it had around 3/8" to 1/2" clearance all around it for air and water flow which might have helped it's longevity. You can see by the pic how tight it is.

 

[rbh]

Re: Fuel tank out - should I paint it?

Re: Fuel tank out - should I paint it?

Let the outside of the tank breath and bond it to the system as was said.

 

[dingbat]

Re: Fuel tank out - should I paint it?

Re: Fuel tank out - should I paint it?

I can see value in patching up a tank that is pitting, and doing a pressure test to avoid a failure, but it looks as though the experts are saying don't bother with the fancy prime and paint??

As I noted above, aluminum is naturally corrosion resistive. It's produces an aluminum oxidize layer on the surface that protects it from corrosion under most circumstances.

You can paint aluminum for cosmetic reasons, but realize that your compromising it's natural corrosion protection by depriving the surface contact with oxygen, opening the window for crevice corrosion to occur.

The best thing you could do for your aluminum tank is keep it clean and dry so oxygen can remain in contact with the surface at all times. Minimize areas of contact with materials that retain moisture. The area of an aluminum tank in contact with wooden support member is prime candidate for corrosion to occur. Moisture permeating a "protective" barrier and getting trapped between the surfaces is another place for corrosion to propagate.

Anyone caught foaming an aluminum tank in place should be shot on site.

BTW: Rubber strips are a real no, no. What a better way to trap moisture than cover something with rubber or plastic.

 

[chriscraft254]

Re: Fuel tank out - should I paint it?

Re: Fuel tank out - should I paint it?

This is sorta like, do I put coolant in when I winterize or not?! Do what you feel comfortable with.

The cost for coal tar epoxy is minimal and will protect the exterior of an aluminum tank from corrosion.

Foaming in a tank has its benefits, mainly from keeping the tank from ever shifting. Bolts and screws sna, there are many threads with evidence of exactly that happening.

Yes, untreated, aluminum tanks properly installed will last 15 to 20 years, some much longer.

The fact is, most of the aluminum tanks that has pits and corrosion are from poor installation from the factories, if they were coated, the tanks probably would have never had an issue unless they rusted from the inside out.

Painting an aluminum tank is completely different than coating it or having it rhino lined.

Yes, a aluminum tank that has plenty of air flow and no moisture getting to it, will last a long time. What boat have you ever seen other than very large ones have enough air flow and no moisture in them?

 

[dingbat]

Re: Fuel tank out - should I paint it?

Re: Fuel tank out - should I paint it?

Yes, a aluminum tank that has plenty of air flow and no moisture getting to it, will last a long time.
What boat have you ever seen other than very large ones have enough air flow and no moisture in them?

My past and present Grady's for one. The tank is blocked in with 2" x 4" so there was at least 1.5" all around the tank. Had roughly 3.5" between the top of the tank and the hatch above and slightly more underneath because of the keel.

Moisture is only problem if it is allowed to stagnate (looses it oxygen content) and starves the aluminum surface of oxygen. Pure freshwater has absolutely no affect on aluminum. Chlorides is the presence of an electrolyte, i.e. saltwater, can causes pitting....however chlorides rarely, if ever cause any structural damage. Keeping standing water off the top of a tank is as simple as keeping the deck plate o-ring in good condition and your deck joints sealed.

No problems with painting if you want to spend the time and expense to do so. Just beware that any type of a coating has a potential to trapped moisture.

Pay your money, roll the dice......

 

[chriscraft254]

Re: Fuel tank out - should I paint it?

Re: Fuel tank out - should I paint it?

If you notice the op's tank had very little room around it. Condensation alone can keep this area wet. If you don't have the proper air flow, its going to rust. Were talking about a tank that is already very old, not a new tank, that should be considered when talking about coating or not. Most fuel tanks you see, including the op's tank out of older vessels are in poor condition. Some foamed, some not.

If the tank is rubbing against anything as the op's tank looks like it could have, it will cause rust and premature failure.

There is a reason that many builders still use foam around the tanks. If they care to plan ahead the tank is covered with something that will protect it before foaming them in.

If the tank is going to be wedged into a coffin type deal like the op's boat , it needs to be secured so it does not move. A lot of tanks come with tabs welded on them for mounting, I have seen plenty of these sheared off or the screws/bolts broken.

Dingbat, I've had two grady's and neither one of them had room around the tank for airflow. Even if they had, the tanks were inside a space that would get very little to no airflow when sealed up. Not saying yours is like that but mine were. Like I said, even condensation can cause issues. The coffin lids that are usually installed are another issue entirely, most people don't maintain a boat like you and I.

 

[film842]

Re: Pulling fuel tank advice needed

After reading a ton of posts and feeling the same way about "when is it going to leak", not if, I am pulling mine to convert the area to a storage and use a transom tank. If you are thinking about downsizing you could put a new tank in and change the layout so it is easier to service in the future. Just a thought.

Not a bad idea. The present tank is a 55 gallon and I don't need that much for the type of fishing and crabbing I do. On the other hand a new tank of almost any reasonable size is spendy.

 

[chriscraft254]

Re: Pulling fuel tank advice needed

You might be able to to fish a strap around the tank towards the bow and then use a pully/comealong to raise it out of there. the hardest part would be to get the strap around it. Remember when talking fuel, you should always have 1/3 in reserve.

You also might want to make sure your tank is empty before doing any cutting around it.

You might be able to take that tank and have it shortened as well if its in salvageable condition.

 

[film842]

This tank thing has got me confused.

This tank thing has got me confused.

My situation is this: As part of the restoration and conversion of my '86 Capri 2150 cuddy to a more fishing friendly boat, I've pulled the gas tank to have a look. It has not leaked in the past and it looks pretty good. Little if any corrosion. I found a local place that will give it a pressure test just to make sure but I can't find anybody who (if it was necessary) will weld an aluminum gas tank. Apparently they can't get enough of the fumes out.

So, I thought well it's not leaking, so how about giving it a coating of something (epoxy?) and re-installing. Maybe even design an installation to make it easy to remove should a problem occur.

Problem is that I have received two kinds of advice from people who sound like they know what they're talking about. Some say pressure test it and stick it back in...no paint. Others say paint it, it will last longer.

At the moment I'm coming down on the no paint side because it's been doing fine in there just like that for a long time already, but I'd hate to miss a trick sooo....

What would you do?

 

[chriscraft254]

Re: This tank thing has got me confused.

Re: This tank thing has got me confused.

Why are you making another post with the same question?

 

[zool]

Re: This tank thing has got me confused.

Re: This tank thing has got me confused.

What I did with mine was clean and prep it properly, then skim coated the pitted areas with jbweld high strength, then painted the exterior with por15 rust prevent paint, came out like new.

Por15 also makes a inside pour in tank sealer you could use for extra protection. (us standard)

US STANDARD FUEL TANK SEALER

the procedure for the prep is in my build thread in my signature link.

 

[Bondo]

Re: This tank thing has got me confused.

Re: This tank thing has got me confused.

Why are you making another post with the same question?

Ayuh,... Great question,...... Mergin' the threads,...

 

[britisher]

Re: Fuel tank out - should I paint it?

Re: Fuel tank out - should I paint it?

The 'rubber' straps should be made of neoprene rubber. It's impervious to oil & gas. You'll find that your original straps were made of it. Can't you recycle them? I did on my 89 SR. Couldn't use all the straps, so cut them up in to pads.

 

[film842]

Re: Pulling fuel tank advice needed

Sorry about reposting. I got my forums mixed up. Will have to be more careful.

 

[Bondo]

Re: Pulling fuel tank advice needed

Sorry about reposting. I got my forums mixed up. Will have to be more careful.

Ayuh,.... Please read the forum postin' rules, 'n guidelines,....

Ya get to post yer question Once, in One forum, the 1 it fits Best in, not every forum it Can fit in,...

This thread now reads bad, because it's 3 threads, 1 from this forum, where it should be, 'n 2 from the drydock,...

I merged 'em, but the timeline stays the same,....

 

[jerryjerry05]

Re: Fuel tank out - should I paint it?

Re: Fuel tank out - should I paint it?

Do the foam thing.
The canned foam is all you need.
You don't want your tank moving at all.
They come fiber glassed in or foamed in.

 

[Fireman431]

Re: Pulling fuel tank advice needed

What would I do if it were mine? Clean it, and put it back in. If it wasn't leaking before, why even go to the trouble of pressure testing it?

If you absolutely have to have some coating on it (why?!?), the look into powder coating. Open your wallet tho $$$.

When reinstalling it, no rubber or neoprene strapping is required. It's not the fact that they're impervious to gas/oil, it's that water gets trapped under the rubber and that leads to corrosion. No foaming is required. Block the tank up off of the floor and secure in place with wooden blocks in the corners or along the edges. Once you add 40 gallons of fuel, it's not going anywhere (260+ lbs plus the tank weight).