An Acceptable Repair or Wimping Out?

[kloudie1]

Non-removable tanks.. The H-34 tank is a poly tank and it cannot be removed without some serious de-construction.. the main fresh water tank is pretty much that way too.. Many boats are built with fuel tanks that cannot be easily removed.. a design mistake in my opinion..

 

[Stu Jackson]

Most boats require some pretty serious disassembly if you want to replace the engine, and that, like tank replacing, is something almost every boat will require at some point.
I think you give boat manufacturers way too much credit for any thought about repairs or replacing things like tanks. Most couldn't care less, once they've got your money.

These are very important considerations. And ones often "missed" by those shopping for old and even new boats. In a shameless plug, my boat has none of these problems and is one of the reasons I bought her. 8 screws opens a panel, and one can (and many have) slide the fuel tank right out and "pop" a new one in.

My "favorite" is what I call "The Dipstick Test." If you have to do demolition derby to get to the oil dipstick, it may tell you that the PO may not have checked it regularly.

So, capta's right: perhaps many, maybe not most, and certainly not all. Some builders DID get it right.

Back to rardi: decommissioning: everything related to it. For example: What will you do with the "OLD" fuel fill? Don't want anyone using it in the future. Think each one all the way through.

Good luck, sorry to hear about your issue.

 

[Jeff]

I had to replace the 20 gallon aluminum diesel tank on my 1993 Hunter 33.5 a few years ago. It began weeping as you describe. I had no access from the cockpit and ended up cutting the bulkhead in the aft berth. The manufacturer's (Etzell) label was still on the tank. I contacted them to see about a replacement. They still had the drawings to make an exact replacement. Just slid out the old and slid in the new one.

 

[Gunni]

Thanks. Then the Darwin Award remarks are unnecessarly alsrmist. You can throw a lit match into diesel and it will just go out.

You know, I understand you have all the answers but you need to acknowledge you really have no experience to back it up. That will get you killed. I managed fuel tank demo for years and had to pick up the pieces, or peel know-it-all fk-ups off the wall because they found safe practice rules restrictive. Tank demo should be done by pros, but at the very least done by a person knowledgeable about the risks involved, how to monitor and mitigate them.

 

[Johnb]

Ridiculous. It's diesel, not gas!

Maybe you should learn something from what just happened. The combination of ignorance and assertiveness and rudeness you just displayed are pathetic.

 

[Ron20324]

You know, I understand you have all the answers but you need to acknowledge you really have no experience to back it up. That will get you killed. ....

OH, come on, Gunni... let him throw the match- he needs the experience.

 

[jviss]

Other than the fact that you'd have oil contaminated water after, is there a compelling reason to purge the tank with CO2 rather than just liquid water?

 

[Justin_NSA]

 

[jviss]

Maybe you should learn something from what just happened. The combination of ignorance and assertiveness and rudeness you just displayed are pathetic.

I admitted I was wrong, what would you like a pound of flesh?

 

[jviss]

You know, I understand you have all the answers but you need to acknowledge you really have no experience to back it up. That will get you killed. I managed fuel tank demo for years and had to pick up the pieces, or peel know-it-all fk-ups off the wall because they found safe practice rules restrictive. Tank demo should be done by pros, but at the very least done by a person knowledgeable about the risks involved, how to monitor and mitigate them.

I defer to your knowledge and experience. I really had no idea. Why aren't blowers, spark arrestors, etc., necessary, as for gas engines? I suppose the conditions, and amount of heat are important for combustion, but I'd like to know more. Is it the heat from a torch or saw that can light it?

 

[capta]

I defer to your knowledge and experience. I really had no idea. Why aren't blowers, spark arrestors, etc., necessary, as for gas engines? I suppose the conditions, and amount of heat are important for combustion, but I'd like to know more. Is it the heat from a torch or saw that can light it?

Basically, it's not the liquid that is explosive or ignitable, but the vapors. The right combination of many things and oxygen can combust. Check out spontaneous combustion online if you want to be haunted for the rest of your life by the nagging worry that your engine rags, paint thinner soaked rags, a bag of wet coal, etc will spontaneously combust one night.
All inboard gas powered vessels are supposed to have spark arrestor carburetors, exhaust blowers ("run blower for 10 minutes before starting engine") and any electrical equipment that goes in the engine space should be certified ignition proof. It is especially dangerous on any gas boat when fueling, as that's when there are more fumes than normal.

 

[quadrille38]

Filling or flushing the tank with water is not going to help much. Diesel fuel is not soluble in water and I don't think it's actually going to help much in your effort to "clean the tank". Additionally you are going to end up with a bunch of oily water that is going to be difficult to dispose of.

It would be illegal to put it in a sewer system. An oil reclaimer isn't going to want it because it's more water then oil.
You might find someone who would "fix" it which is essentially using an absorbent type material to make it a solid and then finding a facility that will accept it for disposal.

As others have suggested, I'd get as much out as you can. Use the inert gas and get a larger opening in the tank that will allow you to pump out and then remove the rest of the liquid before cutting the tank apart.

 

[Skipper]

Additionally you are going to end up with a bunch of oily water that is going to be difficult to dispose of.

You might find someone who would "fix" it which is essentially using an absorbent type material to make it a solid and then finding a facility that will accept it.

He's in California. Nearly every CA public marina has onsite hazmat disposal. Oil, diesel, coolant, even rags and containers.
We have one. It's fantastic. And free.
One of the good things the Eco-Nazis have come up with here.
They're not all crazy.

I'm not advocating for the water treatment, but if he dumped water and diesel mixed, nobody would care. They process the waste.
However, if he needed to drain the tank or for any other future reference, he can investigate onsite disposal, if he hasn't already.

 

[JimInPB]

When cutting fuel oil tanks, there are a few methods that I have seen used in industry. They include:
1) filling the tank with water first
2) filling the tank with inert gas first
3) cutting a big vent hole with a drum deheader (looks like a giant can opener), then ventilating with forced air, then cutting with "hot tools" while still ventilating. Drills & reciprocating saws are considered hot tools.

Choice #3 was the most common.

Once the tank is in open pieces, cutting torches can then be used (on steel tanks) to cut the open pieces up into smaller chunks fast.

 

[jibes138]

Best to replace the tank versus relocation. You want the weight on the centerline of the boat. 30 gals of diesel will weigh 210 pounds or so. I replaced a tank a few years back and documented with photos on this site. I used a Moeller tank for replacement as you are thinking and a little smaller to allow fuel to cycle more frequently, and allow easy replacement. Do a forum search, lots of good info on past projects like this. I used a six gallon tank temporarily to stay operational during the project. PM me if interested in the tank.

 

[jibes138]

You'll probably find the cradle for the tank all oil soaked so plan on some work building and installing some support structure. An oscillating tool is invaluable for this project.

 

[JimInPB]

If a bladder tank is available in a size that fits your current tank, I think that would be my first choice in a boat that has a difficult-to-remove original tank. In the past, I have had good results from tank liner products like Tank Kreem, but they require the tank to be removed for proper preparation & application of the product, so that is not an option here.

You may want to think about your past fuel usage to determine if the size of the original tank was a good fit for you or not. If your fuel was constantly 6-months old or more, &/or needed polishing more than once, then you might want to consider a smaller tank. If you were constantly packing the boat with jerry cans to stretch your range, then you might want to consider a bigger tank, or a second tank.

 

[jibes138]

How can you install a bladder without cutting an opening in the tank? Can you stuff it through the fuel fill or sender cutout?

 

[JamesG161]

you can throw a lit match into diesel and it will just go out.

You can do that with Liquid Gasoline too. The match will go out.

It takes Oxygen at the right mixture with the Vapor of combustibles to ignite.

Good liquid fuel test is...
If you can smell it and you are breathing....

FIRE POTENTIAL !!

Jim...

PS: One key is HEAT. Heat vaporizes Diesel faster.

 

[JamesG161]

compelling reason to purge the tank with CO2 rather than just liquid water?

@Gunni very clever idea using dry ice!!


Cools Diesel and tank, no water contamination, little chance of Oxygen to burn and best of all...

Halloween season "Spooky"

Jim...