Bleach in diesel tank

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Dougcole

Guru
Joined
Jan 21, 2008
Messages
2,167
Location
USA
Vessel Name
Morgan
Vessel Make
'05 Mainship 40T
I'll start by saying in 40 years of boat ownership this is the dumbest thing I've ever done. I was distracted. You can beat me up if you want to, but nothing you can say is going to make me feel any more foolish.


Anyway, I decided to clean my water tanks last night, which is something I do once a year or so, by pouring a little bleach into the tanks, letting it sit awhile then flushing it through. Somehow, I opened the diesel fill instead and poured 4 to 6 oz of bleach into the tank before I realized what I was doing.


There are 60 gallons of fuel in the tank, which hold 150 gallons.


I immediately called the owner of a company I have worked with before who does tank cleaning, tank repair, fuel polishing, fuel storage, fuel disposal etc. He is very experienced, smart and a good guy.



His feeling is that the amount is so small that it probably won't hurt anything and the Racors will spin it out, but I did some googling and some of the results were pretty scary. People sabotage cars by pouring bleach into the gas tank. Now, that is a gallon or more into gas not diesel in a much greater concentration but it still scares me. There is also the possibility of it causing corrosion in the tank.



The active ingredient in the bleach I used is 7.5%, the rest is pretty much water. So there is very, very little actual chlorine (or whatever it is) in the tank, perhaps 1/2 oz.



As a test, I poured two ounces of diesel into a jar then added an ounce of bleach. The bleach immediately fell to the bottom, like water does. But I'm not sure if the active ingredient fell out with the water or if it emulsified. The fuel did not get milky.



Anyway, my guy is coming tonight to pump out the tank, flush it with diesel and dispose of the fuel. It's going to cost me a pretty penny, but I am just too worried about the possible consequences if I don't do it.


I know I am dumb, but am I crazy too? Is this a waste of money and fuel?


Thanks.
 
A few oz to 60 gallons I will agree nothing to worry about. Grab a bottle of the grey power service to add extra luberciticy to the fuel and run them down or top them off to dilute it more and run it down. I would tho add some extra luberciticy to the fuel.
 
i doubt the fuel polisher will get to those few Onces of bleach anyway.

add some additives including water dissolving ones and forget about it.

just my opinion.
 
Maybe your insurance policy covers the costs. My wife (now ex) filled one dieseltank with 200 liters of water. The insurance company covered the costs because it was caused by something coming from outside of the boat. I do not know whether the same rules apply in your country but it is perhaps worthwile investigating it.

Good luck.


Paul
 
It may not hurt and the Racors may catch it, but what does an engine rebuild or even an injector pump rebuild cost?
 
It may not hurt and the Racors may catch it, but what does an engine rebuild or even an injector pump rebuild cost?

That’s what it came down to for me. Probably would be fine, but the potential penalty if it is not fine is just too high.

Im pumping it out now.
 
I wouldn't be so sanguine about 4 oz of bleach mixed with your fuel. Bleach is sodium hypochlorite (hey I am a retired chemical engineer) and I suspect it could react with some of the additives that are in the diesel and maybe not in a good way. It may deactivate some of them, leaving you with less protection.

So here is what I would do. Contact your fuel polishing guy again. Dump a few gallons of fresh water into the tank, maybe five while running the engine until the Racor shows the water being picked up. Then have your fuel polishing guy suck it all out. That will dilute the sodium hypochlorite many times by sucking out the contaminated water. If you do it right you can dilute the sodium hypochlorite a hundredfold all for the cost of a simple water removal job.

Now the question remains- is the remaining diesel compromised. To be really, really sure, then remove the fuel as well and fill with fresh. I suspect that will cost a few bucks not to mention the cost of the replacement diesel.

David
 
Doug
There is a bright side to your oops. You now will have a tank that has been properly cleaned. :thumb:
 
I wouldn't be so sanguine about 4 oz of bleach mixed with your fuel. Bleach is sodium hypochlorite (hey I am a retired chemical engineer) and I suspect it could react with some of the additives that are in the diesel and maybe not in a good way. It may deactivate some of them, leaving you with less protection.

So here is what I would do. Contact your fuel polishing guy again. Dump a few gallons of fresh water into the tank, maybe five while running the engine until the Racor shows the water being picked up. Then have your fuel polishing guy suck it all out. That will dilute the sodium hypochlorite many times by sucking out the contaminated water. If you do it right you can dilute the sodium hypochlorite a hundredfold all for the cost of a simple water removal job.

Now the question remains- is the remaining diesel compromised. To be really, really sure, then remove the fuel as well and fill with fresh. I suspect that will cost a few bucks not to mention the cost of the replacement diesel.

David


This is close to what we did. I pulled an unused return pick up off of the top of the tank, then we slid a piece of semi rigid nylon tubing (about 1/4" ID) down into the tank until it hit the bottom. We then hooked it up to the big pump on his truck which creates a ton of vacuum (he told me how much but now I don't recall what he said) and sucked the tank dry. Then blew about 20 gallons of clean diesel back into the tank under pressure and sucked it out too. Discarded all of the old fuel.



Tomorrow, as per his advice, I am going to add PriD for Lubricity and Startron for water removal to the tank and put at least 75 gallons of new diesel in. Let it sit for a few weeks, then run the boat pretty hard watching the racors closely.


He called a few other fuel guys that he knows well and that was their suggestion as well. He thinks I'm safe.


I do like the water suggestion, thanks you for that, but I think we got the tank pretty dry. The tube went all the way to the bottom at the lowest part of the tank.


Expensive, $400 plus the lost fuel, but it gives me peace of mind.
 
I’ll bet he is thrilled about that…


Silver lining, I guess. Doesn't feel like much of one.


The lost fuel was from the Bahamas, which can be sketchy at times, so I am telling myself that that is a silver lining too. Delusion can be a good thing sometimes.
 
Any contact with a "real" diesel fuel expert...like from a refining company?

One might have been able to tell the good the bad and the ugly if you had just topped off the tank and added an additive or two.
 
The consultant may have charged more than the $400…
 
I once had a lawsuit in which my client was a fuel supplier. In a break in the action I asked about fuel contamination by being put in the wrong tank at a station. His response was something about 10% being allowable contamination, didn't matter what was the contaminant.
 
Any contact with a "real" diesel fuel expert...like from a refining company?

One might have been able to tell the good the bad and the ugly if you had just topped off the tank and added an additive or two.


Good suggestion, but I'm not sure where I would even start to find someone like that. I read some stuff that it is important to get the bleach out of the tank as soon as possible, so I didn't want to wait.


One of the people that my guy called is from a refinery, not sure at what level. He was sort of unsure as well, and agreed that the safest move is to get rid of the fuel and clean the tank.
 
Good suggestion, but I'm not sure where I would even start to find someone like that. I read some stuff that it is important to get the bleach out of the tank as soon as possible, so I didn't want to wait.


One of the people that my guy called is from a refinery, not sure at what level. He was sort of unsure as well, and agreed that the safest move is to get rid of the fuel and clean the tank.

Yeah, getting through to the people you really want to speak to is tough...it has been hit or miss with those level people for me in my career. A petroleum engineer (or whatever title) could have been hard to find quickly...just a thought though. My point was to get to the level where the guy could actually tell you what might be going on in the fuel and if it would degrade below the typical engine specs.

I may have started with Blackstone (my oil sample guy) as they also do fuel I think. If they do, they might have the kind of contacts to start the ladder climb of petroleum specialists.

I never recommended calling a "consultant"...its funny how some can never think out of the box and are destined to limited courses of action.

Me, I might have tried the "add 5 gallons of water, let it settle out, pump it out, top off the tank and let MR. Racors and an additive do the rest." or debated a bit/heeded caution and pumped it all out ASAP, found something to neutralize the bleach and a bit of rinse and pump, and replaced the fuel. Now about the pumped out 60 gallons. Those I may have sat on till I found out more about the mixture because now I had the time.

It's amazing the quality of fuel that much of the world burns and a one time shot in your engine I doubt would have spelled doom based on the dilution factor. But I still would have looked for some top tier advice/research.
 
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Since the fuel tank was only about 1/3 full, why not just fill your tank all the way? This would further dilute any bleach and harmful chemicals.

Cheers, Bill
 
Since the fuel tank was only about 1/3 full, why not just fill your tank all the way? This would further dilute any bleach and harmful chemicals.

Cheers, Bill

it's now bleach under the bridge for the OP
 
As a side note, I question the design choice to put the fuel and water fills on my boat immediately adjacent to each other. I'm sure it made some sense from a plumbing design standpoint, but I feel like if they were at different locations in the deck, maybe by a dozen feet or so, there would be less likelihood of making this kind of mistake. Inside the boat, the fuel and water tanks are separated fore and aft buy quite a bit. They did put the pumpout quite a bit farther aft even though it's almost in the same fore/aft location as the water tank. Bit of a head-scratcher, probably just not something they thought of.
 
Since the fuel tank was only about 1/3 full, why not just fill your tank all the way? This would further dilute any bleach and harmful chemicals.

Cheers, Bill




I considered that, but when I did the jar test with some diesel and an ounce of the bleach solution the bleach sat on the bottom of the jar, like water does. It did not emulsify into the fuel. As I said earlier, household bleach is only 7.5% active ingredient, the rest is water. Maybe the sodium hypochlorite mixed in with the fuel and the water fell out but it is hard to say.


So adding more fuel would not have diluted it anyway and since the bad stuff is on the bottom of the tank it would have either sat there forever (corroding the tank?) below my pickups or would have been sucked into the fuel filters. Maybe they would have spun it out, maybe the startron would have emulsfied it, maybe not. It's just not worth the risk.


And if I did fill the tank all the way and it didn't work, then I would have had 150 gallons of bad fuel to deal with rather than 50.


I don't think there is a single right answer here. I think I took the most conservative choice.
 
It's probably worth it just for the peace of mind. 50 gals is not the worst thing. I probably would have done the same.
 
At least you have a happy ending. It’s only money.
In a month you’ll be laughing about it ( ok maybe in a year).
Cheers!!
 
Thanks for making me feel a little better everyone. On top of this my son blew out his knee (tibial plateau fracture) mountain biking. It’s been a rough couple of days.
 
Greetings,
Mr. DC. Although you had an "oopsie", it appears to be a lot less severe, expensive and long term than doing the reverse. For example: Pouring a quart of bio-bor or fuel conditioner into your water tank.
 
A friend of mine who was the 3rd Mate on a large tanker, was responsible for a crew member's pumping the wrong fuel into the wrong hold, essential ruining the whole batch of petroleum. It was not even his error, but as the 3rd Mate he is responsible for overseeing the loading and off loading of cargo. It cost him his job with that company, and almost his career.

So, in the grand scheme of things, mistakes are relative.

I agree. I'd have done the same thing as you. Thanks for sharing the story with us. It helps us to be mindful of even the little things. I'm finishing up a solar panel project on our boat. "No short cuts!" = No Fires. Right?!
 
I'll start by saying in 40 years of boat ownership this is the dumbest thing I've ever done. I was distracted. You can beat me up if you want to, but nothing you can say is going to make me feel any more foolish.


Anyway, I decided to clean my water tanks last night, which is something I do once a year or so, by pouring a little bleach into the tanks, letting it sit awhile then flushing it through. Somehow, I opened the diesel fill instead and poured 4 to 6 oz of bleach into the tank before I realized what I was doing.


There are 60 gallons of fuel in the tank, which hold 150 gallons.


I immediately called the owner of a company I have worked with before who does tank cleaning, tank repair, fuel polishing, fuel storage, fuel disposal etc. He is very experienced, smart and a good guy.



His feeling is that the amount is so small that it probably won't hurt anything and the Racors will spin it out, but I did some googling and some of the results were pretty scary. People sabotage cars by pouring bleach into the gas tank. Now, that is a gallon or more into gas not diesel in a much greater concentration but it still scares me. There is also the possibility of it causing corrosion in the tank.



The active ingredient in the bleach I used is 7.5%, the rest is pretty much water. So there is very, very little actual chlorine (or whatever it is) in the tank, perhaps 1/2 oz.



As a test, I poured two ounces of diesel into a jar then added an ounce of bleach. The bleach immediately fell to the bottom, like water does. But I'm not sure if the active ingredient fell out with the water or if it emulsified. The fuel did not get milky.



Anyway, my guy is coming tonight to pump out the tank, flush it with diesel and dispose of the fuel. It's going to cost me a pretty penny, but I am just too worried about the possible consequences if I don't do it.


I know I am dumb, but am I crazy too? Is this a waste of money and fuel?


Thanks.

I did almost the same thing. Decided to try to clean up the inside of my holding tank with some laundry detergent. Put it in the fresh water hole. Man I flushed it 4 times before it got the laundry smell out of it. Stupid is as stupid does.
 
Bleach.JPG
There are worse things one can do with bleach!
 
You did the right thing imho. The oxidative properties of the chloro could reek havoc or passed harmlessly but why take the risk? Besides, Bahamian fuel can be iffy at times, lesson learned! So, did you ever get the water tank sanitized?? :rofl:



I considered that, but when I did the jar test with some diesel and an ounce of the bleach solution the bleach sat on the bottom of the jar, like water does. It did not emulsify into the fuel. As I said earlier, household bleach is only 7.5% active ingredient, the rest is water. Maybe the sodium hypochlorite mixed in with the fuel and the water fell out but it is hard to say.


So adding more fuel would not have diluted it anyway and since the bad stuff is on the bottom of the tank it would have either sat there forever (corroding the tank?) below my pickups or would have been sucked into the fuel filters. Maybe they would have spun it out, maybe the startron would have emulsfied it, maybe not. It's just not worth the risk.


And if I did fill the tank all the way and it didn't work, then I would have had 150 gallons of bad fuel to deal with rather than 50.


I don't think there is a single right answer here. I think I took the most conservative choice.
 
It's sounds like a done deal now but how temperamental is your engine(s)? A new highly strung, common rail, electronic everything relies on good fuel. An old 671 will drink anything.
 
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