Diesel tank pitting

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mike cunningham
Posts: 489
Joined: Sat Dec 20, 2008 11:21 am
Location: Jacqueline, F30 #3, Discovery Bay, California

Diesel tank pitting

Post by mike cunningham »

Anyone who has read my saga regarding white smoke and injectors will know I have had water in my fuel tank. This has resulted in pitting of the tank interior in a small area around the fuel uptake where the tank is deepest. Those pits are eventually going to turn into leaks. The vast majority of the tank is in perfect condition. I am wondering if the community thinks it is feasible to remove the tank and ask a fabricator to cut out the small pitted area and re-weld a replacement plate in there. It seems crazy to have to replace the entire tank to fix about 4 square inches of pitted interior surface.
Mike Cunningham
Freedom 30 (Mull) Hull #3
Build date...June, 1986 . Freedom Yachts USA, sloop, shoal keel
Gun Mount and pole retrofitted (purchased from a Hoyt Freedom 32)
Yanmar 2gm20F , 1600 hrs fixed two blade prop
e-rud and ocean racing equipment

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rvivian
Posts: 210
Joined: Sun Feb 21, 2010 2:08 pm

Re: Diesel tank pitting

Post by rvivian »

Hi Mike -

Before you cut into a non-leaking diesel tank maybe you should consider coating the affected area (if you can reach it) or try coating the tank innterior with a specialty lining material like: http://www.northernfactory.com/UserFile ... lletin.pdf to try and prevent leaks from developing.

My tank started leaking a few years ago and I took it out and replaced it with a new one from the original tank manufacturer used by Freedom located in Florida. They still had the original specs and dimensions and shipped me a new tank matching the original for about $750.
Heart's Desire
Freedom 30
Shelton, WA

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mike cunningham
Posts: 489
Joined: Sat Dec 20, 2008 11:21 am
Location: Jacqueline, F30 #3, Discovery Bay, California

Re: Diesel tank pitting

Post by mike cunningham »

Yes, I can get into the tank and get at the pitted area. Thanks for the link. I will check this out. I was wondering, but forgot to ask, about possible interior coatings.
Mike Cunningham
Freedom 30 (Mull) Hull #3
Build date...June, 1986 . Freedom Yachts USA, sloop, shoal keel
Gun Mount and pole retrofitted (purchased from a Hoyt Freedom 32)
Yanmar 2gm20F , 1600 hrs fixed two blade prop
e-rud and ocean racing equipment

Lionel7
Posts: 32
Joined: Fri Dec 05, 2008 12:12 pm

Re: Diesel tank pitting

Post by Lionel7 »

My surveyor a few years ago told me about a liquid paint like product that you can use to line the interior of fuel tanks. It is a product designed for the aviation industry so my thinking was if it worked in that highly regulated environment it would work in a marine environment. You might be able to just "paint" the area of pitting at the low spot in your tank if you have a suitable access port to reach it.

Doug
Freedom 21 Maketea
Previously Freedom 28 Free at Sea

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JohnReinagel
Posts: 94
Joined: Mon May 08, 2017 1:44 pm
Location: Suburb of Buffalo, N.Y.

Re: Diesel tank pitting

Post by JohnReinagel »

Hi Mike,

On my last sailboat, a 1973 CAL 29-2, I used KBS Coatings on the leaky aluminum diesel tank with great success. The tank does need to be removed from the boat and is quite a process, but the results were impressive. The coating felt hard as a rock but when I bent some test patches that I painted onto other surfaces, they flexed without issue. As a matter of fact, I kept bending to see if the coating would crack, it did not. The inside of the tank looked brand new of course and I had enough material left over that I coated the exterior also. The tank held pressure as expected. If I recall the kit I needed for a 20 gallon tank was under $100.00.
John


1984 Hoyt F32
Hull #53

Erik
Posts: 35
Joined: Thu Dec 14, 2017 7:24 pm
Location: Stony Point, Hudson River New York USA

Re: Diesel tank pitting

Post by Erik »

To All
I am currently removing my fuel tank in a 1983 Freedom 33 Cat Ketch. What a PITA the tank is beyond repair. The tag on the tank is unreadable does anyone know who made the tank. Any help would be appreciate.

Thanks Erik
33 Cat Ketch # 74

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drcscruggs
Posts: 81
Joined: Tue Apr 03, 2018 3:06 pm
Location: Galveston, Texas

Re: Diesel tank pitting

Post by drcscruggs »

I don't have any idea who made the tank. Having said that I think it would not be too difficult to find a fab shop to make you a new one using the old one as a pattern. I think I would do that. I am near Houston and there are many fab shops around here. I believe due to the petrochemical business. Best

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rvivian
Posts: 210
Joined: Sun Feb 21, 2010 2:08 pm

Re: Diesel tank pitting

Post by rvivian »

The tank for my 1986 Freedom 30 was manufactured by"

Aluminum Fabricated Products
PO Box 1088
Perry, Fla 32347

904 584-6898

I ordered a new tank from them in 2011 and they still had the tank specs and dimensions. The new tank matched the original and dropped right into place.
Heart's Desire
Freedom 30
Shelton, WA

Erik
Posts: 35
Joined: Thu Dec 14, 2017 7:24 pm
Location: Stony Point, Hudson River New York USA

Re: Diesel tank pitting

Post by Erik »

Thank you will give them a call Monday
Erik

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