Will start building a fuel tank for my project soon and have a couple questions. The tank will be 175gal. and will be for twin 4 cylinder 4-strokes.
Should I use welded aluminum pickup tubes and what size tubes do I need? Pic shown below.
Do I need to acid wash the inside the tank before welding on the top plate?
Fuel tank build
Re: Fuel tank build
we make ones similar to this and use 1/2" sch pipe (7/8" od) we put a 1/2 x3/8 s/s bushing in the top and than a hose barb fitting.
welderbob
welderbob
Re: Fuel tank build
Do I need to acid wash the inside the tank
Re: Fuel tank build
we have never heard of anyone acid washing the inside of a tank.There is no reason why you couldn't as its clean and dry when your done.
Bob
Bob
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kmorin
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Re: Fuel tank build
w'bob, I acid etch/wash all my tanks inside and out.
The 95% failure was water bottoms becoming acidic and working/enhancing the galvanic difference of the mill scale to underlying alloy- to pit the tanks. Pin holes from the inside out! I etch and haven't had any tank failures like the ones I see in mill scale lined tanks?
I pour straight Zep-a-Lume in the tank when the pressure test done so any leaks are repaired, roll the tank on the bench or on the floor on boards if it's large. I add water a couple of times and continue the process. Then I drain the tank and flood/rinse four or five times and finally let the hose fill the tank and overflow for a couple hours.
When that is done I add acetone and repeat but no water flood. I've plugged a filter or two in my day with MIG soot so I'm particularly touchy about getting the insides cleaned.
If left to my own devices I'd etch the outside too. IF possible run a buffer on the tank parts before you build- skip the etch - since the mill scale is all gone with the 3M pads or drum sander.
I use oversize draw pipes so that plastic fuel hose will fit in them, and that allows a foot filter to be fitted to the end of the plastic hose- this can be removed by pulling the draw tube liner. I always try to have water bottom sumps in my tanks- sometimes it won't work- but I like the fuel draw and water bottoms to be separated 'ala-Navy practice' so the water bottoms can be lifted and not go to the filters.
Others prefer to have all the bottoms come up and get trapped in the filter bowl? As long as you get them out- either method seems to work?
Cleaning tanks either before or after building of the mill scale is super important to me. But then I'm the site's Mill Scale gnat-zee so any time I hear about mill scale on aluminum its a given; I rant.
Cheers,
Kevin Morin
Kenai, AK
My thinking on this is formed by the repair and replacement of hundreds of tanks - almost all production boat tanks- with the mill scale intact inside.welderbob wrote:we have never heard of anyone acid washing the inside of a tank.There is no reason why you couldn't as its clean and dry when your done.
The 95% failure was water bottoms becoming acidic and working/enhancing the galvanic difference of the mill scale to underlying alloy- to pit the tanks. Pin holes from the inside out! I etch and haven't had any tank failures like the ones I see in mill scale lined tanks?
I pour straight Zep-a-Lume in the tank when the pressure test done so any leaks are repaired, roll the tank on the bench or on the floor on boards if it's large. I add water a couple of times and continue the process. Then I drain the tank and flood/rinse four or five times and finally let the hose fill the tank and overflow for a couple hours.
When that is done I add acetone and repeat but no water flood. I've plugged a filter or two in my day with MIG soot so I'm particularly touchy about getting the insides cleaned.
If left to my own devices I'd etch the outside too. IF possible run a buffer on the tank parts before you build- skip the etch - since the mill scale is all gone with the 3M pads or drum sander.
I use oversize draw pipes so that plastic fuel hose will fit in them, and that allows a foot filter to be fitted to the end of the plastic hose- this can be removed by pulling the draw tube liner. I always try to have water bottom sumps in my tanks- sometimes it won't work- but I like the fuel draw and water bottoms to be separated 'ala-Navy practice' so the water bottoms can be lifted and not go to the filters.
Others prefer to have all the bottoms come up and get trapped in the filter bowl? As long as you get them out- either method seems to work?
Cleaning tanks either before or after building of the mill scale is super important to me. But then I'm the site's Mill Scale gnat-zee so any time I hear about mill scale on aluminum its a given; I rant.
Cheers,
Kevin Morin
Kenai, AK
kmorin
Re: Fuel tank build
Another question should I sit the tank on top the aluminum ribs in my boat are put some type of Teflon on rubber between the fuel tank and the ribs?
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kmorin
- Donator 08, 09, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24
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Re: Fuel tank build
joe,
I don't mean this in any rude way, buttttt....... please use the Search function for related topics- Why? I think we've been around this bush quite a bit. There are plenty of tank related threads and posts to explore, I've posted quite a few myownsef so I'd say they're here some where?
In general, size, construction details, welding procedures, methods to build, mounting and plumbing considerations seem like they have been explored here in the past?
too busy to take time to find them all, re-post and show the images and sketches provided, but I think there's a gold mine for you in the many possible searches you could do related to tanks?
Cheers,
Kevin Morin
Kenai, AK
I don't mean this in any rude way, buttttt....... please use the Search function for related topics- Why? I think we've been around this bush quite a bit. There are plenty of tank related threads and posts to explore, I've posted quite a few myownsef so I'd say they're here some where?
In general, size, construction details, welding procedures, methods to build, mounting and plumbing considerations seem like they have been explored here in the past?
too busy to take time to find them all, re-post and show the images and sketches provided, but I think there's a gold mine for you in the many possible searches you could do related to tanks?
Cheers,
Kevin Morin
Kenai, AK
kmorin