proper fuel tank install......

froggy1150

Master Chief Petty Officer
Joined
Nov 3, 2017
Messages
802
i felt froggy so i am going to leap on this one! thanks kcassells. this is strange doing this on a computer, i am a phone guy.
i have read "yacht survey fuel tanks install" ~ 4 times. i have read alot of posts here and on other less worthy forums.etch with alodine, paint, dont paint, open air, rhinoline....... it was last year i did most of my research and had settled on this if i remember right. acid etch, coat with gluvit to seal and refoam in cuz thats how it was originally. i always read as much as possible and have not installed tank yet.i read kcassells debate a few weeks ago ( we are listening, thanks) and started second guessing my plan. i am going to follow the open air procedure. i will have to do some rework to make it structurally sound because that area was foam but safety is foremost! knowing whats safe and doing less is negligent. i have read that coating with epoxy is good, and have also read that if you coat it can crack and hold moisture. i have read to just etch with alodine or zinc cromate. also have read that if its open air it will produce its own protective coating.about the only thing thats consistent is to support with neoprene. i went thru the " how to sticky" and i didnt see this covered either and because there is so many opinions on whats right and whats acceptable. i didnt include this on my post but kept it seperate and maybe it can go into the how to section when its got some good info in it. sooooooo how to prep? how to coat?support? hold in position with and with out mounts? etc....... let the debate begin!
 

kcassells

Fleet Admiral
Joined
Oct 16, 2012
Messages
8,596
Oh my.....So soon you will hear.."this topic/discussion" is an old topic. and look around.
Like I said before on-one will give you the right answer only their interpretations. Ea. one seemingly will have a flaw.
Then again maybe someone has some great interpretation.
You go boy!
 

froggy1150

Master Chief Petty Officer
Joined
Nov 3, 2017
Messages
802
so over the past few days i have read for hours and hours. several different forums articles etc...... alumina prep & alodine,
open air on welded tabs..... oh dont weld tabs cuz they cause stresses and crack. set on neoprene strips with them glued to tank and hull with 5200...... oh dont glue to hull so it can shift..... but chock so it dont move. dont adhere anything to tank.... coal tar epoxy in foam is the way to go, no paint with epoxy paint. then full circle to alodine with epoxy paint. oh dont forget vinegar acid etch. head is spinning and really dont have a definitive answer. i do know i want it safe. i will have my son on mine and i have already lost a child so i dont want to risk anything. i knew this was a toxic topic but when it comes to safety on the premier boat building forum ........
 

sphelps

Supreme Mariner
Joined
Nov 16, 2011
Messages
11,432
Well I saw the bait but unfortunately I must sniff then move on ..
I honestly have never dealt with a fuel tank under the deck . I’ve never had a boat large enough to even consider using one ..
All I can say is do some research .. :rolleyes: :joyous:
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
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Jul 23, 2011
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47,496
FWIW

My pristine 32 year old tank had butyl rubber strips under it, and along the sides with 3/4 strips of marine ply under it and wedging between the tank and stringers

on top was a few pieces of marine ply strips holding the tank.

When I put it back in, i will use butyl rubber and pieces of delrin with dynema webbing to hold it down

Air can get under and around

When i had it painted, it was snow white axalta (imron)
 

NatedoggAZ

Petty Officer 2nd Class
Joined
Mar 7, 2018
Messages
182
I just took my tank out a few weeks back.. I have an under floor tank setup as well....

My tank had 3 strips of.... something.... taped onto the bottom of the tank.... I am guessing it was neoprene.

Each about 2 or so inches wide. One on the front, one in the middle, and one in the back.

Friscoboater put together a video which I just watched yesterday ... because I have the same dilemma as you.

https://www.youtube.com/watch?v=y_ge8qSFMwg

I plan to do something similar possibly with rubber floor mats... but I heard that rubber may not be the best thing.
If I can find neoprene, I will use that.

I do not think I will use the 3M 5200 sealant to bond in the straps...
I have some Loctite Marine Sealant which should work just fine.

ND
 

froggy1150

Master Chief Petty Officer
Joined
Nov 3, 2017
Messages
802
Rubber is a big no no. So is dissimilar metal fittings. Like brass touching aluminum. Those are things that are gospel. The rest is up for debate. When I pulled tank last year I researched everything I could find and never got good results. I have just done a second loop around the same articles and I did watch Frisco. My tank was treated with aluminaprep/alodine and was in decent shape and is 45 years old. I did have to tig a bit to fill in minor pitting. Less than 20% loss in the deepest spot. And wasn't much but I did build up to original thickness. I was foamed in. So I will continue searching for answers for a bit before tank goes in. Maybe a month
 

froggy1150

Master Chief Petty Officer
Joined
Nov 3, 2017
Messages
802
Didn't think I was letting this die ...
so I am going to say concensus is to not foam a tank back in unless some one has a different opinion.
1. How to coat / or to even coat?
aluminaprep then alodine,
2. then epoxy paint? Or coal tar?
3. I guess in my install it has to sit on neoprene strips that sit on glassed wood on the hull. 5200 to bond neoprene to tank directly or glue to whatever coating it gets?
 

chevymaher

Commander
Joined
Mar 29, 2017
Messages
2,915
I used weather strip adhesive and glued the neoprene to the boat. Factory it was just in there nothing holding it.
 

froggy1150

Master Chief Petty Officer
Joined
Nov 3, 2017
Messages
802
So that's 2/0 for not bonding to the tank but to the wood support on the boat. Any dissenting opinions?
and 0/0 on how to coat....
 
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