POR 15 Tank Sealer for a gas tank?

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rgano

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Panama City area
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FROLIC
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Mainship 30 Pilot II since 2015. GB-42 1986-2015. Former Unlimited Tonnage Master
Friend with three 100-gallon gasoline tanks in his boat has found one leaking at the bottom. Luckily, all is now safe. It would cost half the value of the bat to remove engines and tank to replace, and he is considering having the tank treated with an internal coating of this PUR 15. Any experience or comments?
 
I'm not sure this will be of help, but... one thought: Before I decided to do tank replacements for my boat, I looked into several coatings. I don't remember if PUR 15 was one of them. The thing that dissuaded me was that all the examples I found (videos etc) required that stuff be poured in, then the tank rotated & rolled around to make sure the entire interior was coated. Easy for a motorcycle tank, maybe even a car gas tank. To do that for big tanks installed in a boat stumped me.
 
I have used it to refurbish a corroded RV batty bay / tray. It is advertised as acid resistant but don't recall it claiming to be a fuel resistant sealer.
It is tough stuff but I brushed it on and don't know how you would get complete coverage inside a tank?
 
I wonder if somebody has figured out a way to spray it in in the same way professional diesel fuel tank cleaners shoot diesel fuel at the interior surfaces of diesel tanks to dislodge tank crud?
 
My biggest concern would be whether it's ethanol resistant in the long term. Even if you generally avoid ethanol I wouldn't want a known incompatibility there.
 
Greetings,
POR15 does make a coating for fuel tanks. BEST to call the company and ask THEM the questions. I've used their paint and it lived up to what they claimed. VERY reputable company IMO!
Fuel Tank Restoration
 
I could maybe be convinced to try sealing a diesel fuel tank but a gas fuel tank, I don’t think so because if it starts leaking again it could be a serious problem. Have you ever seen a gas powered boat explode, I have.
 
RG
Is the tank Fe or Al? If Al the leak could be a sign of corrosion that once started may be difficult to stop. I’m with Comodave, be careful. Me, I’d replace the tank. What model of boat?
 
A friend's boat on SF Bay a few years ago......I forget the cause.

Reminds me of the skydiver who had both parachutes fail. As he's free-falling, he see's a man heading up as fast as he's headed down. As they pass, he shouts "Hey.....do you know anythng about parachutes???" The man yells back "No! Do you know anything about Coleman Stoves??"

Peter

boat fire.jpg
 
I used that system to coat the top outside of one of my fuel tanks. Its a 3 part process. Degreaser, primer, then the” paint”. I dont see how ypud get the degreaser and primer in the right place inside the tank.
But if you do try to use that system, you need a respirator.
 
For a gasoline tank rather than coat the tank if the boat is not worth the cost to replace I'd abandon the tank and live with the reduced range. The risk is simply too great.
 
I had a 1989 Lien Hwa 47 back in 2007-2009. One of the steel diesel fuel tanks was leaking. I had a professional clean the fuel and tank using the POR15 system. Cleaned, "the cleaner smells just like 409", rust reversal, and epoxy coating. Because of the economy I had to sell the boat. The new owner called me a year later and told me the fuel tank was leaking again. Replacement is best or POR15 and sell it.
 
So POR-15 does make a gasoline tank repair kit. The only negative I have hear on POR-15 is that it hardens and becomes brittle. This leads to hairline cracks which can allow moisture penetration which could lead to future leaking.

As regards to safety, I wouldn’t have a boat like that with out having vapor monitoring. With vapor monitoring I would be comfortable with the safety aspect.
 
Back before I decided I needed a more ruinously expensive hobby (boating), I used to fix up old muscle cars. POR15 was a staple for sealing up rusted body panels (something ubiquitous in old American cars). It does an amazing job of binding with rust, sealing a corroded part, and preventing future corrosion. But I would not trust it for use on anything mission-critical, nor anything which I expected to come in contact with fuel or other non-water fluids. It's also not structural, and as tiltrider notes, doesn't really have any flex to it when it's in place. If it's on something that will be under stress (a fuel tank wall, for instance) or flex at all, it WILL crack.
 
One more thing. My current boat developed a fuel tank leak and I replaced the aluminum tank. Expensive? Yes but worth it. If you want to read further, I planned to replace both aluminum tanks since, if one leaks the next one will. But when we cut out the mid line 265 gallon tank I found several factors. It was built into a portion of the bilge under the aft stateroom bed that was cut off from the rest of the bilges. Under the bed was first the water tank, then the fuel tank. The water tanks had been replaced so they originals must have leaked and then the water sat in the closed bilges holding the tank. To prevent vibrations there were rubber pads spaced here and there along the length of the tank. Those pads held the water against the tank and that is where there was corrosion. So then I just replaced that tank as the other 400 gallon tank was well lifted above any water in the bilge.
 
I once repaired a gasoline tank. The tank was removed from a race car neutralized and the crack was grounded and tig welded.

I once repaired a diesel tank. The tank was removed from its location but could not be removed from the boat. Because of the location welding was deemed unwise. After preparing the tank for repair we had a 1/4” hole and a surrounding 6x6” area with mild pitting. An epoxy putty was worked into the hole and coated the pitted area. An additional 18” was coated in G-flex epoxy with glass roving added for strength.

I have never attempted to repair a diesel tank without removing the tank.
 
I have used Caswells Gas tank sealer 4 times and have had excellent results. This was for small tanks that were removed, cleaned and sealed. One tank had a pinhole in the top that they recommended putting tape over and then seal. worked out very well and the tank is still in service 8 years later.

For a non removeable diesel tank with an inspection port, I would drain tank, clean the area that needs sealing (probably the bottom) and then pour some sealer in and then roll it out and up the walls. This would be my plan!

I would definitely call Caswells and get their input on partially covering the inside of the tank vs. 100% coverage.

 
I had a diesel tank repaired with a 2-part epoxy (Splash Zone). My research showed that one common use was for the repair of airplane tanks (avgas) so diesel is not a problem. Three inspection ports were cut (because of two baffles in the tank). Tank was cleaned and pressure washed. Not completely dried because Splash Zone adheres to wet surfaces. Troweled on to the steel tank like plastering a wall. Two years w/o problem. Don't expect any in my lifetime.
 
I am familiar with Splash Zone. I am unfamiliar with it as a tank sealer. Nowhere does Pettite (the manufacturer) recommend it as a tank sealer. This of course does not mean it won’t work. I would like to see more information on it as a tank sealer.
 
RG
Is the tank Fe or Al? If Al the leak could be a sign of corrosion that once started may be difficult to stop. I’m with Comodave, be careful. Me, I’d replace the tank. What model of boat

RG
Is the tank Fe or Al? If Al the leak could be a sign of corrosion that once started may be difficult to stop. I’m with Comodave, be careful. Me, I’d replace the tank. What model of boat?
Agree with Sunchaser, corrosion has to be remediated and surface prep is critical in a gas environment, I wouldn’t be comfortable at all.
 

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