Diesel tank - non removal repair option?

[Bongi]

I have the regular rusted original diesel tank issue. I was told there's an option which avoids cutting them out and replacing with multiple aluminum tanks.

It comprises cleaning them out, cutting a large hole into them for access and then applying an industrial polymer over the entire interior. Then preparing and covering the entire exterior with the polymer. Essentially this makes the tank immune to future corrosion even if the decks / filler leak. Companies offering this supposedly offer a lengthy warranty.

Has anyone tried this?

 

[koliver]

I have the regular rusted original diesel tank issue. I was told there's an option which avoids cutting them out and replacing with multiple aluminum tanks.

It comprises cleaning them out, cutting a large hole into them for access and then applying an industrial polymer over the entire interior. Then preparing and covering the entire exterior with the polymer. Essentially this makes the tank immune to future corrosion even if the decks / filler leak. Companies offering this supposedly offer a lengthy warranty.

Has anyone tried this?

Before you decide to do anything drastic you will need to investigate properly, exactly what your tank problem is. This may not be easy, or it may be much less of a problem than your first fears would suggest.
Here is one possibility: http://www.belzonabc.com/

Best of luck

 

[Bongi]

Thanks Keith, I will give them call to ask more about their experience with this. Great point to fully investigate all parts of these tanks and the nature of the corrosion source, impact and repair options.

 

[Steve1.0]

I just replaced the tanks in my 46. It was a b*!%&ch. Here is a photo of the inside of the original 350gal. steel tank. Lots of baffles, not sure how you would coat the entire inside surface.

 

[Max1]

This is a timely post as I am in the same boat.
I have a starboard tank that was un-serviceable when I got the boat. I have no idea what the true condition of the tank is. I was only told "It leaked".
I am looking for an option that lets me re-coat it (seal it?) from the inside(?)

Will go the multiple tank route if I need to, but I don't want to.

 

[Max1]

I just replaced the tanks in my 46. It was a b*!%&ch. Here is a photo of the inside of the original 350gal. steel tank. Lots of baffles, not sure how you would coat the entire inside surface.

Ah- good point. I should mention that my tank is a long rectangle about 18" high, about 20" deep and about 8 feet long.
It is stuffed into the narrow space between the decking on top of the boat and the hull bottom. Not sure how I would even get it out other than cutting it out

Not in a hurry to make a decision yet. I can always make a bad decision tomorrow....LOL

 

[Larry M]

Here’s a thread that discusses coating the inside of diesel tanks.

https://www.trawlerforum.com/forums/s6/diesel-fuel-tank-repair-internal-coating-3719.html

I have used Flamemaster 3204 but as Steve mentioned, the baffles make it hard to access the entire tank.

 

[Marco Flamingo]

I went with the non-removal fix. The tank that was leaking is 125 gallons divided in to three sections. I hired it out and would recommend that for most owners. The equipment for repair isn't that complex, but having somebody with the experience and equipment was worth the expense. Plus, he had +30 gallons of diesel/water/solvent, etc. to dispose of when finished, which he offered to email me the receipt from the HazMat site showing the fees he paid. It was also low tide when he hauled it up the gangway. I couldn't have done that.

He put in three inspection ports. My corrosion was almost entirely the bottom plate on the tank. Just a few little rust spots on the sides. We never did find the actual pinhole leak. He used a plastic goop that is unaffected by water and, with a helper, spread that 1/8" thick on the bottom of the tank and up about 4 inches to clean steel on the sides and baffles. Took about 6 hours and cost $2,800. I was offered a cut rate should I decide to do the other tank (which I probably will before it starts leaking).

My tanks are covered with a skim coat of fiberglass, so the leak in the tank didn't align with the leak in the fiberglass coating. It was a little discomforting to have the tank weep for a few days after, but since then not a drop. With a new plastic "basin" in the bottom of the tank, and basically zero corrosion on the upper parts of the tank, I think that tank is probably good for another 75-100 years.

The actual cost of the plastic goop used is only about $200, which might inspire a DIY. Having seen the process, I'm still not tempted.

 

[cks]

I used Belzona to fix my ss water tank. It took ALL summer to actually locate the hole.
Once found I used Belzona and used the excess ss when I cut a hole into the tank to create a cold patch. Belzona is an amazing epoxy.

 

[Max1]

I used Belzona to fix my ss water tank. It took ALL summer to actually locate the hole.
Once found I used Belzona and used the excess ss when I cut a hole into the tank to create a cold patch. Belzona is an amazing epoxy.

Is Belzona resistant to diesel fuel?

 

[cks]

Yes.

 

[Slowmo]

The in place repair using a polymer is commonly used on commercial vessels, so it is a well proven approach.

 

[neworleansrich]

Exactly which Belzona epoxy is used for a diesel tank repair?

 

[koliver]

Exactly which Belzona epoxy is used for a diesel tank repair?

Belzona 1161, to coat the affected area, this is the peanut butter consistency epoxy. It is pressed into corners with the back of a spoon.

Followed by Belzona 1341. This more like a paint and is applied over the 1161 and to a wider area. It flows and will wick into tighter places to guarantee a good seal.

 

[SteveD]

I see you are in the Seattle area. I had my leaky tanks repaired by Felix Marine Industries. They come to your boat, pump out the fuel, cut enough access holes to get to each part of the tank and spread around some epoxy goo. It is definitely not cheap, but it beats the alternative. So far all seems to be well.

 

[syjos]

I see you are in the Seattle area. I had my leaky tanks repaired by Felix Marine Industries. They come to your boat, pump out the fuel, cut enough access holes to get to each part of the tank and spread around some epoxy goo. It is definitely not cheap, but it beats the alternative. So far all seems to be well.

What is the size of your tank and cost to repair?

How long did the process take?

 

[SteveD]

There were two tanks (one on each side). About 160 Gallons each. The final bill, which was about 2K over the estimate, was about 7K. I don't think the job took longer than a week, although my memory is hazy on this.

It looks like the business has been absorbed by a bigger one (cleantank.com). I am not sure if they are still doing this kind of work or not.

 

[HuffinandPuffin]

Inside out?

Disclaimer: I have no experience with this. Repair on the inside seems like it might work well if the deterioration is on the inside but I am under the impression that often these tanks are rusting from the outside inward. If that were the case, I’d be concerned about a catastrophic failure eventually resulting.

 

[SteveD]

Sometimes they do rust from the top, such as when water leaks past the fill. In my case the problem was condensation and bugs in the fuel, so it was leaking from the inside and the bottom of the tank.

 

[Arc]

I have used many Balzona products. I blame myself. Probably poor prep , but I never had any long term luck. Sealing the inside of a tank using a spoon with multiple baffles would be near I possible

 

[Capt. Carman]

Diesel Tank - Non Removal Repair Option?

I had scaling rust on the top of my tanks but zero leaks. I have used products from POR-15 to seal rusty fuel tanks. Spoke with their engineering folks and they recommended repairing/sealing the tops using a four step process.


1. Use a metal blade scraper to knock the scaling rust off and get as much rust off as possible. Vacuum the bigger bits off.
2. POR-15 De-greaser - follow their instructions
3. POR-15 Metal Prep - this neutralizes/stops the rust and puts a really heavy layer of rust prevention. Follow their instructions.
4. POR-15 Tank Sealer/Final Coat - Colors to choose from. I used a roller to apply this on my tanks. Once it sets it is hard as a rock.



I did ask if I found small holes in the the top and he told me they have a sealer for that.



Might give them a look....

 

[Efftea]

I have the regular rusted original diesel tank issue. I was told there's an option which avoids cutting them out and replacing with multiple aluminum tanks.

It comprises cleaning them out, cutting a large hole into them for access and then applying an industrial polymer over the entire interior. Then preparing and covering the entire exterior with the polymer. Essentially this makes the tank immune to future corrosion even if the decks / filler leak. Companies offering this supposedly offer a lengthy warranty.

Has anyone tried this?

the polymer coating has no structural integrity. if the tank is rusted then it may be wise to get the metal thickness checked with an ultrasonic tester. I think they are around $100. If its thin, you could apply some Pultruded FRP sheet on the outside if you don't want to weld.

 

[Bongi]

You guys are amazing! This is a treasure trove of wisdom in this this situation. Thanks for the replies and contributions. Will indeed check out the options. Thanks for the pointers - will fill you in on how it goes. Will add some photos as we tackle this.