Black iron fuel tanks

[Comodave]

Wow. Never heard of someone cutting out tanks that weren't leaking or visibly about to. On the smaller Grand Banks, even if one moved the engines, the only way to get old tanks out & new ones in was to remove salon windows.

I am starting to plan on replacing my fuel tanks since they are 32 years old. They are not leaking nor do they have any rust that I can see but the tanks have insulation around most of the tanks so I really cannot tell if they are rusting or not. My thinking is that at some point they will need replacing. I am getting to the point that in 5 or 6 years I may not be able to physically do the work anymore so why not do it when I am still able rather than paying someone a small fortune to do the work when they start leaking, besides it will probably happen at the most inconvenient time and place. I will have to pull one engine and stack it over the other engine. Then I believe I can get the tank out and back in in one piece. I can also access components that I cannot get to now. It would be nice to clean and paint the engine room, replace some hoses, water heater, etc. Still in the planning stage and will see, but I would like to do one tank this winter and the other one the next winter.

 

[PM]

P.O. did mine shortly after he bought the boat. It is vintage 1978 Albin (Taiwan). First the engine comes out then the saddle tanks. I would have replaced them but he elected to have the bottoms cut off and new bottoms installed. It reduced the capacity from 150 gls to about 130. That was around 12 years ago. The cost then was around $8,000. A recent sampling showed my fuel to be crystal clear. It is a comfort but I agree, all T.T.s will face the problem eventually.

pete

 

[Aquabelle]

P.O. did mine shortly after he bought the boat. It is vintage 1978 Albin (Taiwan). First the engine comes out then the saddle tanks. I would have replaced them but he elected to have the bottoms cut off and new bottoms installed. It reduced the capacity from 150 gls to about 130. That was around 12 years ago. The cost then was around $8,000. A recent sampling showed my fuel to be crystal clear. It is a comfort but I agree, all T.T.s will face the problem eventually.

pete

Pete....how did your friend manage to cut the bottoms off the tanks and replace them? Was the cutting and welding all done in the engine room?

 

[PM]

No, the tanks were removed. I don't think they could be worked on in place, just no room. One nice feature of them coming out is that they now have a heavy coat of some type of epoxy on them. Albin tend to leak along the walkway and the water lays on top of the tanks, mine are at least somewhat protected.

Here is an interesting story from my previous life as a restaurant owner. I had the bar rebuilt and added three new "stations" behind the bar for peak periods. That means three new 3 compartment wash sinks. The furthest one never got used. One summer we developed fruit fly invasion. I told the bartenders to pour a cup of bleach down each sink each night, which they did.One day the third station was needed and as we filled the sinks to wash glasses every one of the three sinks was full of pinholes. The labels were still on the sinks! I was mad and called the manufacturer. He simply told me to read those labels. Plain and simple language, "Don't use bleach on Stainless Steel unless is is diluted and flushed"
Who would have thought, Bleach eats stainless steel.

pete
.

 

[Redhook98]

I had 1 400-gallon and 4 175-gallon tanks on my 79 49-ft MT PH. They were all rotted so bad that they had gaping holes in the tops. (Rotted out decks). They were replaced with 2 150-gallon barrel SS tanks. I now have ample room around the engines and no huge 400 gallon tank lurking in the middle of the ER. 300 gallons will get me thru a year at least. I am good with that.

 

[Heron]

Pete....how did your friend manage to cut the bottoms off the tanks and replace them? Was the cutting and welding all done in the engine room?

My friend did that but the tanks were also removed. Unfortunately they had to come out the side of the boat through a 4x6 ft cut (Shannon 36). Aluminum tanks that had pinhole leaks in the bottom. Fabricator cut the bottom off, welded in a new one and he re-installed. The fiberglass guy was a genius and you cannot tell the boat was ever cut open...

 

[Moondance]

I cut out my tanks on my 82 Marine Trader 44. Engines were out so access was easier. Used a sawzall. Had tanks drained but they really weren't and I had to remove lots of fuel in 5 gal buckets. They actually had a drain valve, so that part was easier, tho lugging up the buckets and off was difficult. Designed 4 saddle tanks and a day tank, fabricated by Luther in RI. Covered the tanks in West System epoxy and fibreglass mat and then painted with Awlgrip.

It is one hell of job, I wouldn't do again.

Installed the new tanks on platforms. Day tank is gravity fed. Had my buddy put all the fitting on the tanks (not easy). Haven't used them yet as I can't find anyone in Montauk to put engines in the boat.

 

[Comodave]

I had 1 400-gallon and 4 175-gallon tanks on my 79 49-ft MT PH. They were all rotted so bad that they had gaping holes in the tops. (Rotted out decks). They were replaced with 2 150-gallon barrel SS tanks. I now have ample room around the engines and no huge 400 gallon tank lurking in the middle of the ER. 300 gallons will get me thru a year at least. I am good with that.

What does the missing weight from the 400 gallons do to the trim?

 

[Hawkeye]

Replaced mine in our 1981 Heritage about 15 years ago. Was working on a soft spot on the walkway, saw rust on top of a tank and signs of pooling diesel (had just topped up.) Pulled the fuel deck flange up and sure enough the sealant from time of factory build was spotty, both sides of the boat--the source of the water that puddled on top of the tanks over the years, rusting through. Got an estimate from a yard whose owner told me that some insurance companies cover "hidden defects at time of manufacture." Long story short a very expensive remove/replace project was fully covered by insurance, less deductible. The following year, that "hidden defects at time of manufacture" had disappeared from that insurance policy's language. (As we all know, all boats probably have hidden defects of one kind or another.)

 

[Redhook98]

What does the missing weight from the 400 gallons do to the trim?

With the water tanks full (both all the way aft, about 150 gallons each also) and both fuel tanks full, the bow raises about an inch or so. I have a mystery stainless steel tank under my V-berth that I will probably fill with water to try and counterbalance a little. Otherwise, not as much of an issue as I thought it may be. Just filled up the tanks for the first time in 18 years after the resto/refit.

 

[Comodave]

Well that sounds good. Glad it is working out for you.

 

[kapnd]

Nothing wrong with mild steel tanks, I've seen many that were quite old and had no problems.
They also didn’t sit in bilge water or have leaking decks above them.
If I had to build new tanks for my boat, they’d certainly have built in sumps and slanted tops so that any water would drain off towards the centerline.
A sight glass with valves would be nice too!

 

[pacificsailors]

We have a 1980 Monk 36 and one of our original steel tanks started leaking last season. We are in the processing of replacing our two tanks with four aluminum tanks. We believe they started leaking because they were not raised off the deck enough and were standing in moisture.

Lots of photos of the process on our website: https://pacificsailors.com/2019/05/diesel-tank-replacement.html

Don't let it stop you from buying a boat! Every boat is a project boat!

 

[T210DRVR]

Hello, I am looking at mid 1980 Taiwan built trawlers. Some have black iron diesel fuel tanks. I have no background knowledge about these type of fuel tanks. I would appreciate any comments concerning their reliability and what can be done if they develop problems (i.e. aside from finding a leak is there a way to inspect them, can they be repaired or must they be replaced, for a typical mid 1980 Taiwan trawler is repair/replace as big an undertaking as it would appear?). I realize that that there are many factors to consider for any particular boat, and that answers to board questions will be generalizations. But any information I learn will be helpful. Thanks in advance.

The best option for replacement is to have the old tanks cut out in pieces. Then replace with fuel tank(s) that will fit into the current opening. There are several options for replacement material ranging from stainless (expensive) to Aluminum and even fiberglass. There are pros and cons for each type.

If the tanks haven't been replaced in the past consider the replacement cost in your offer. They will need to be replaced sometime in the near future.

 

[Dave_E]

If a tank is rusted out from the top... might be in trouble. See my posting:
http://www.trawlerforum.com/forums/s3/42-year-old-tank-42523.html#post731969.


Dave

 

[88FuHwa]

Ours is a 1988 TT with a single Perkins. One of the steel tanks developed a leak which caused a lot of the diesel to empty out in the bilge. Mind you it must have been a very small hole or crack but I failed to discover the location of the leak as the diesel was seeping out. A minor panic, a big cleanup job and very expensive as spilled diesel is considered a hazardous material. I pumped out the tank, installed a new access cover plate, cleaned the bottom, but could not find any rust or obvious signs of a leak source. I have been filling the tank again slowly. It is now 1/3 full and still no leak so the area must be higher up in an area that I cannot see or have access to. Maybe I have to learn to live with it and run the engine using the other tank only. Replacing the tank is too expensive but I like the idea of cutting it out and replacing it with two smaller plastic tanks.
Great forum and excellent suggestions, Thank you.

 

[Deckape]

Here it what happen to me. Purchased a 1988 jefferson 45 twauler/motor yatch. Not knowing how long fuel had been in tanks, had the fuel cleaned. Tank guy got alot of crap out and said I might want to have fuel tanks cleaned. Did that and got alot more crap out , (rust hard pieces etc, ) . Filled tanks up and headed to the keys. After about a month smelled diesel and find a tank leaking. After removing tanks and cutting them up, inspecting them found that cleaning tank removed rust on inside walls and exposed the rusted thru areas on the tank walls. Would be vary cautious of tank cleaning as it removes scrabs on walls and exposes the hole and leak. Be careful of tank cleaning.

 

[jimisbell]

I had two 100 gallon tanks on my Bruce Roberts 44. The hull was steel and was one side of each of the tanks. The starboard tank failed and replacing it would require cutting out the side of the hull. I sold the boat.

 

[Gypsy Diver]

Hello, I am looking at mid 1980 Taiwan built trawlers. Some have black iron diesel fuel tanks. I have no background knowledge about these type of fuel tanks. I would appreciate any comments concerning their reliability and what can be done if they develop problems (i.e. aside from finding a leak is there a way to inspect them, can they be repaired or must they be replaced, for a typical mid 1980 Taiwan trawler is repair/replace as big an undertaking as it would appear?). I realize that that there are many factors to consider for any particular boat, and that answers to board questions will be generalizations. But any information I learn will be helpful. Thanks in advance.

[FONT=&quot]Hello. I have a 1983 Island Gypsy trawler with the original black iron tanks port and starboard. Mine each have two access plates that are screwed on using rubber gaskets. While not easy, this at least makes a partial inside inspection possible if the tanks are empty.[/FONT]
[FONT=&quot] [/FONT]
[FONT=&quot]Once I had the fuel "polished", which involved, in my case, taking all the fuel out of the tanks, cleaning and inspecting the inside, and pumping the fuel back in through a series of filters. My technician did not find any problems with the tanks.[/FONT]
[FONT=&quot] [/FONT]
[FONT=&quot]I myself have noticed sheets of rust accumulating in certain areas ON TOP of the tanks from time to time. I attribute this to rain water leaking in around the filler spouts. I scraped and painted those areas myself, which was no easy task given the space limitations.[/FONT]
[FONT=&quot] [/FONT]
[FONT=&quot]I have also heard that if one keeps the fuel tanks full, that allows less space for condensation to form, which can sink to the bottom of the tank as water.[/FONT]
[FONT=&quot] [/FONT]
[FONT=&quot]Good luck.[/FONT]

 

[venturadave]

Fun times

Newbie Question: in picture #2 above, it looks like mold in the area where the fuel tank was located. We will be boat shopping next March for our first big boat, but I'm nervous about mold on boats. My wife is very sensitive to it, so the prospect of mold (especially black mold) could put the kibosh on our plans to live aboard. I've been told by several sailors that mold is controllable with proper maintenance. But seems like things like this fuel tank are difficult to detect and could sneak up on you? Any feedback would be appreciated.

 

[jimisbell]

If you or wife is sensitive to mold....buy an airplane, not a boat. ALL boats have mold on them. Dont let ANYONE tell you otherwise.

 

[Eagle Pursuit]

I won't post my pictures because they look exactly like timb's. Mine failed because the fiberglass tabbing that was holding it in place allowed water to sit against the tank and.... Fail....

If only the tank had been place in a pedestal and blocked in so it stayed dry all the time it would still be there.

 

[Jakers12.]

I can only speak for Marine Trader boats. Whether their tanks are any good depends on the year. After 1986 they stopped using teak decks hence they stopped deck leaks and eliminated fuel tank issues. Teak decks are the problem not the mild steel fuel tanks.

 

[psneeld]

I can only speak for Marine Trader boats. Whether their tanks are any good depends on the year. After 1986 they stopped using teak decks hence they stopped deck leaks and eliminated fuel tank issues. Teak decks are the problem not the mild steel fuel tanks.

Teak decks aren't the only source of saltwater leaks.... a bad fuel fill or vent hose inlet could transport salt water to the tank top.


Tanks that rust from more from the top or inside out can be a problem too.

 

[Stormin54]

I have a 1985 Cheer Men PT 38 with twin Perkins 135s and two 165 gallon steel tanks. This spring we were shocked to find about 250 gallons of fuel in the bilge. The tanks had inspection ports fore and aft that appeared to ever being removed. Additionally the drains were an inch from the bottom so water could not be drained. I opened the ports and removed the sludge to find water corroded the bottoms. I could not see the center of the tanks due to the baffles.


I was able to remove the two 90 gallon stainless steel water tanks, one aft of each tank, pull the tanks back and past the engines and remove them.


I had new tanks fabricated out of aluminum with a 2 inch sump in the center with a ball valve for draining.


The steel tanks looked brand new from the outside but only took about a cup of water to corrode the bottom.

 

[Portage_Bay]

We have a 1980 Monk 36 and one of our original steel tanks started leaking last season. We are in the processing of replacing our two tanks with four aluminum tanks. We believe they started leaking because they were not raised off the deck enough and were standing in moisture.

Lots of photos of the process on our website: https://pacificsailors.com/2019/05/diesel-tank-replacement.html

Don't let it stop you from buying a boat! Every boat is a project boat!

Where did you find a place that will allow such a DIY project?

Who is your tank fabricator?

 

[MVDarlin]

I have a 1982 Ocean Alexander with 2 x 300 gallon steeltanks. I had them cleaned two years ago. They cut access ports in the top and removed the baffels and sent a man inside. 5 gallons of bio goo was removed from each tank. Baffels were reattached. Tanks were in fine condition.

 

[sunchaser]

If a vessel has any water in the tank bilge bilge when boat shopping, assume it is coming from the fuel tank tops or bottoms. Then, have owner or broker prove to your 100% satisfaction where the water is emanating, or be prepared whether tanks are mild steel or aluminum.

 

[Stormin54]

I replaced the tanks while on the hard and was lucky that only about a gallon of fuel went on the ground. The marina was happy to let me do all the work due to a small staff and lack of time. It so happened that the marina owner also owned the fab shop where the new tanks were made so he made some profit there.

 

[kapnd]

Here it what happen to me. Purchased a 1988 jefferson 45 twauler/motor yatch. Not knowing how long fuel had been in tanks, had the fuel cleaned. Tank guy got alot of crap out and said I might want to have fuel tanks cleaned. Did that and got alot more crap out , (rust hard pieces etc, ) . Filled tanks up and headed to the keys. After about a month smelled diesel and find a tank leaking. After removing tanks and cutting them up, inspecting them found that cleaning tank removed rust on inside walls and exposed the rusted thru areas on the tank walls. Would be vary cautious of tank cleaning as it removes scrabs on walls and exposes the hole and leak. Be careful of tank cleaning.

If your tanks are so fragile that they won’t stand a good cleaning, repair or replacements are long overdue!