Leaking diesel fuel tanks

stubones99 said:

Check out Amazon for their boroscope or endoscope which is simply a tiny camera in a brass housing at the end of a long USB cable. Plug the USB cable into your laptop and fish the camera end wherever you want to see. The camera end has a few LED's to light up the area around the camera in darkness.

Range in cost from $15-$30 for up to 20' length. Good to go exploring all over a boat. They are waterproof so you can tape it to a boathook and check out your prop / rudder, and even bilge areas.

Fiber optic cameras are far more expensive due to the fiber bundle accuracy. Also, they are length restricted since you get loss by the foot.

Stu

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What you mention is what I was talking about. Just used the wrong term in a generic way.

Giggitoni
I have used the POR15 system. It takes four days to cure. I'll let you all know how it turned out on the 27th. Just by chance, have you gotten a ball park estimate for replacing the tanks in your boat?

Ball park estimate is about $18,000. Good luck with the Por15.

A friend told me he was quoted $46K for new tanks on his 1988 GB 42.
Your price sounds a lot better. I will try to get back into the Grand Banks Owners Resources but it's been awhile and I'm not sure that was the same name of the organization. Is there more than one?

Click on this link for the Grand Banks Owners forum, Grand Banks Owner's Resources.

I've seen tank replacement for a GB42 on the west coast go as high as $25,000.

Giggitoni
I have tried to get into the GB forum thru your link and no go. I can't get past the password. I asked for help and they have not answered. There has to be a simple reason for this but I can't find it.
Be well
Tex

Tex, you need to register and then its reviewed by the admin for approval and then you will have access, at least that is what I went through, found it a bit more difficult then it needed getting approval for some reason.

I have been following along, have used Por 15 on cars I have restored, but on a large fuel tank with a good amount of pressure within it not really the way to go, so where there is one hole there is most likely more waiting to happen. All the best.

The hole is the spot where an AREA of corrosion comes down to zero. Right next to the hole it's a few thousandths, next to that a little more. The proper thickness of the original material can be many inches away. Rarely does one find a pinhole in otherwise solid material.

On the GB the culprit is the leaky teaky (screws) and/or the filler hole and it's surroundings. For YEARS water leaks on the top of the tank, and dripping down the sides, often unseen. The small leak is the last stop before, you guessed it, the large leak.

No magic elixir is going to cure this, nor do you WANT to be on a boat where hundreds of gallons of fuel are being kept from spilling by a wad of chewing gum. Think about it.

Do it right.

fuel tank leak

Feel free to send me a private message and I can put you in touch with my contact at American Tank, should you decide to take that route.[/QUOTE]


What is the approximate price for a project like this?
Thx

Cappie,

The cost of old tank removal, manufacturing new custom tanks, installing the new tanks and other miscellaneous tasks depends on access in ones engine room and access from the outside of ones boat into the engine room.

In my case I'm removing two 300-gallon tanks (one on the port side and one on the starboard) for a total of 600 gallons. The old tanks will be cut up in place. I'm having six smaller tanks constructed (three on each side) for a total volume of about 520 gallons. The tanks will be plumbed together "as one tank" on each side. The reason for the smaller tanks is to accommodate limited access to my engine room from the outside of the boat (as stated in previous posts above).

I expect the total cost to be about $18,500. I feel great about the price! I was prepared for costs to be in the $25,000 to $28,000 range.

I will document the work on this forum when it commences.

Tex Stephenson said:

A friend told me he was quoted $46K for new tanks on his 1988 GB 42.
Your price sounds a lot better. I will try to get back into the Grand Banks Owners Resources but it's been awhile and I'm not sure that was the same name of the organization. Is there more than one?

Click to expand...

For $45,000, I will fly to the boat, rent a motel, cut out the old tanks, build in place fiberglass tanks to any controlling authority specs.

Where do I sign up?

That was a company that didn't want the work.

I'd like to thank all of you for your thoughts and advice. Tomorrow I will put in 100 gallons in the port tank and see how it goes. My wife has been resistant to removing the teak decks which would have allowed the diesel fill cap to be sealed properly and possibly avoided this problem or postponed it. In my mind the POR15 is a stop gap procedure to let me have time to examine my choices.
Be well
Tex

Tex,

One doesn't have to remove the teak decks in order to reseal the diesel fill caps. Search this forums archives or go to www.grandbanksowners.com and search their archives for methods to accomplish the task.


Edit: I found a good source for resealing your deck fuel fill. I "lifted" it from the Grand Banks Owners site.


"One of the problems with sealing deck fills for fuel, water or waste, is that they get pretty hot in the sun. This will tend to melt the oil based bedding compounds like Dolphinite.

When bedding the deck fill to the deck surface, most of the bedding is squeezed out so the benefit of cold flow of the urethane caulks is pretty much all lost since there is little left to cold flow.

The best method I have found and used successfully is to use a hole saw the size of the deck fill flange plus 1/4" all around (if the deck fill is 4" then use a 4 1/2" hole saw) and cut to a depth of the flange thickness plus 1/4" or so.

Use deck seam compound to bed the deck fill fitting. Make sure the deck fill is installed flush or a bit proud with the deck. The goal is to fill the voids under the deck fill fitting and all around it so that when cured, any excess can be trimmed and the deck fill will be sitting in and on a nice thick gasket that seals it all around and under. "

Greetings,
Mr. TS. Before you do put in the 100 gallons, have the equipment and material close at hand to immediately be able to pump it out into another thank if things go south.
Regarding the fill cap...Rather than removing the teak could you not simply remove a ring of teak around the fill large enough to allow you to do a repair?
I defer to Mr. G who beat me by 1 minute...

All
I put in 100 gallons, checked for leaks, forced the return fuel to go into the tank until they were equal, and then continued south. Two hours later there was some seepage. It appears to stop leaking when the boat is at anchor and weep when underway. Better but not perfect. It does not even fill an oil diaper for the whole day. I still feel better now though because I have time to get quotes and find where I can do the job.
Giggitoni, the GB forum still has not answered me. Disappointing
I'm working the booth for the MTOA at the Trawlerfest down it Riviera Beach, FL., and a guy came up to join, saw my boat card and told me he has a 46 GB with a bad tank also. Who knew!!! If anyone has dimensions on replacement tanks, I'd be grateful.

Tex, Did you just put the primer coat of Por on or did you follow with the paste?

Tex Stephenson said:

All
I put in 100 gallons, checked for leaks, forced the return fuel to go into the tank until they were equal, and then continued south. Two hours later there was some seepage. It appears to stop leaking when the boat is at anchor and weep when underway. Better but not perfect. It does not even fill an oil diaper for the whole day. I still feel better now though because I have time to get quotes and find where I can do the job.
Giggitoni, the GB forum still has not answered me. Disappointing
I'm working the booth for the MTOA at the Trawlerfest down it Riviera Beach, FL., and a guy came up to join, saw my boat card and told me he has a 46 GB with a bad tank also. Who knew!!! If anyone has dimensions on replacement tanks, I'd be grateful.

Click to expand...

The tank installers will have to take custom measurements based on your equipment and their placement in your engine room. These boats are all different; exhaust systems, generator types, turbo or naturally aspirated engines, height of engine mounts, location of black-water holding tank(s), etc.

Therefore, if you plan to come close to matching your current tank volume and want as few tanks as possible, very accurate measurements will have to be made. I've read about folks who even built mock-up tanks out of foam to see if they could fit them into place in the engine room and then constructed the tanks from the models. Good luck!

I agree with the repair method below with some elaboration. Remove a ring around the fill large enough to remove the deck core and form a solid fiberglass ring around the fill opening. Once that is done make a solid teak or composite circle to fit between the fiberglass deck and fill fitting to level the deck fill with your existing teak deck. Bolt it all down tightly with new bedding.

You need to stop all the water paths. If you do not leakage into your deck core from other areas may find its way to the deck fill opening, leakage through seams in the teak may find their way to the deck fill opening and if the fill cannot be pulled down tightly its own caulking may fail. Solid laminate and a ring around the fill fitting is as good as it gets in keeping with the original design.

RT Firefly said:

Greetings,
Mr. TS. Before you do put in the 100 gallons, have the equipment and material close at hand to immediately be able to pump it out into another thank if things go south.
Regarding the fill cap...Rather than removing the teak could you not simply remove a ring of teak around the fill large enough to allow you to do a repair?
I defer to Mr. G who beat me by 1 minute...

Click to expand...

After following this type of issue for years on TF and talking with local yards it seems:

1. Old plug style teak decks and fuel tanks buried beneath are problematic.

2. Salon windows that leak can put water onto fuel tanks

3. Deck fills can leak

4. Some fuel tank placement designs are water traps

So, buyer beware when looking at vessels suffering these build and maintenance issues.

All
I used the three step process which is meant to be used INSIDE the tank. I took my time and did it after speaking with the factory representative in New ROCHELLE NY. Oddly enough that's where I keep the boat in the summer. Never knew they were there. Using mirrors, I can see the area is near the corner weld just over a rubber support pad. I would like to use two tanks per side. Two tanks totaling 200 to 250 per side would be great, giving me 400 or 500 gallons total.

All
Thank you for all the advise. I'll be sure to try to seal the decks as you have advised. After the Trawlerfest I'll try to make specific measurements.
Be well and again, Thank you
Tex