Deprecated: Function set_magic_quotes_runtime() is deprecated in /var/www/vhosts/tartan37.com/httpdocs/t37forum/common.php on line 88 Tartan37.com • View topic - Replacing fuel tank

Tartan37.com

Tartan 37 Owner's Forum - Ride the wind, but look good doing it!
The time is 25 Oct 2020 15:04

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 32 Posts ]  Go to page Previous  1, 2, 3, 4  Next
Author Message
 Post subject: Re: Replacing fuel tank
PostPosted: 21 Jan 2019 10:19 
Offline
Midshipman

Joined: 31 May 2017 22:18
Posts: 65
Location: Gulf of Mexico
Thank you so much for the quick reply and the photos! I agree, the thought of cutting it out sucks, but setting it up so that I can access it again in the future with out cutting is nice. Thanks for sending the pictures, the idea about adding the lip is priceless. I was trying to think about how to make it so that I would not have to glass it back in and that's just the tip about the lip is exactly what I needed.

One last question, leaving 3 inches still left you enough space to get the tank out? Knowing what you know now, would you have made that larger/smaller? Or was that just about right?

I'm on my way to the store now to pick up a fresh blade and get to work.

Thanks again!

Kirk

Mike wrote:
I cut along the hull,,, stayed about three inches away from the hull wall so I could use it for a tab to connect the bunk floor when it was ready to be re-installed. As I said in the previous post, the bunk floor is screwed in on one side so all the cutting is along the outside hull wall.

If the level of diesel in your tank is below the sender/inspection port and you still have diesel pooling down around the nav desk/nav seat I'd say it's leaking because all hoses connect above that point; the vent hose and filler hose.

Once I cut the bunk floor out and removed it,,,, a quick look down and I could tell that my tank was indeed leaking. When I re-installed the bunk floor and I installed it so I could remove it quickly if necessary. .... SO removing it might just be worth it in the long term to be able to inspect the tank when needed. Just a thought...

Oh to answer your question specifically,,, I added a lip on the piece I cut out and connected it to the 3" tab side with screws,,, so the bunk floor simply sits back in ,,, screws on one side and the lip resting on top of the tab side.... some folks have simply connected it with Fglass but I like the idea of removing it when I want.

I have attached 3 pictures, two are of the tank with the bunk floor removed. You can see how the tank is held in place,,,, metal straps... the third pic is the rusty corner of my tank,,, that corner was cut out and rewelded.


 
 Profile Email  
 
 Post subject: Re: Replacing fuel tank
PostPosted: 22 Jan 2019 03:42 
Offline
Skipper

Joined: 09 Jul 2008 12:51
Posts: 250
I didn't have any trouble getting the tank back in or out due to how much was left after cutting... as for exactly how much I left... it was about an inch on the other side of the gray tabbing strip that runs along the hull. I'm going to the boat today and I'll do a quick measure and let you know.


 
 Profile Email  
 
 Post subject: Re: Replacing fuel tank
PostPosted: 22 Jan 2019 22:23 
Offline
Skipper

Joined: 14 Jul 2012 20:36
Posts: 411
One of the main problems that causes leaks, is water sitting in bottom of the tank. Once a year it's a good thing to pull the sending unit and use a hand scavenger pump to suck the water and junk out. Also the biocides are very corrosion to aluminum. Never add more than what's recommend and add before filling the tank and run the motor some after adding.

_________________
Hull #208, Puff Card
Southern Chesapeake Bay


 
 Profile Email  
 
 Post subject: Re: Replacing fuel tank
PostPosted: 23 Jan 2019 08:34 
Offline
Skipper

Joined: 09 Aug 2017 15:35
Posts: 457
Location: Maine/USVI
puffcard wrote:
One of the main problems that causes leaks, is water sitting in bottom of the tank. Once a year it's a good thing to pull the sending unit and use a hand scavenger pump to suck the water and junk out. Also the biocides are very corrosion to aluminum. Never add more than what's recommend and add before filling the tank and run the motor some after adding.


And right there is the answer. I've replaced tanks in several boats. A "bubble" of freshwater, brought into the boat through hundreds and hundreds of fills, sits in one spot, particularly on the hard, with all of the diesel "floating" on top of it. I had a stainless tank in my Bristol 35 leak fully into the bilge on the hard. By God I couldn't find a hole in the tank, just a discolored area. I found it with magnification. Miniscule corrosion the size of a pinpoint. It was in a dusty yard on Mt. Desert Island, the cockpit scuppers filled with leaves and the seat scuppers filled with dust. It all flowed over and into the bilge, eventually, lifted the fuel over the floorboards, and what a mess. I put a custom baffled, welded plastic tank in, was never real happy with it. It worked, but I think the welds got brittle, especially at the fill and vent. On my Navy Utility (google "Uniflite 50 Navy Utility" - that's the boat, the one with the tuna tower) both 120 gallon stainless tanks let go. I'm a firm believer in aluminum with diesel. I replaced one 80 gallon aluminum tank in a friend's fishing boat. The foam around the tank held bilge water against it from underneath. It looked like someone shot it with 12 gauge buckshot. You need air circulation and drainage, not a sealed chamber underneath. Go easy on the foam.

What I do now with aluminum is clean it, clean it, and put a layer of Gluv-it on the tank before installation. Seems to do the trick, and its a relatively cheap preventive measure.


 
 Profile Email  
 
 Post subject: Re: Replacing fuel tank
PostPosted: 23 Jan 2019 12:32 
Offline
Skipper

Joined: 14 Jul 2012 20:36
Posts: 411
A friend is currently replacing his aluminum fuel tank, I talked him into spraying the outside bottom with Line-X the bed liner. Like the Idea of coating the bottom of the aluminum tanks and keeping the inside clean.

_________________
Hull #208, Puff Card
Southern Chesapeake Bay


 
 Profile Email  
 
 Post subject: Re: Replacing fuel tank
PostPosted: 23 Jan 2019 15:47 
Offline
Skipper

Joined: 09 Aug 2017 15:35
Posts: 457
Location: Maine/USVI
We Gluv-it over the whole tank. Then it gets ratchet strapped down. No rainwater gets to sit on top of it, etc. Let's see, aluminum I used to wipe down with white vinegar after cleaning with acetone. Some boat guy told me that before painting masts and stuff down in St. Thomas.


 
 Profile Email  
 
 Post subject: Re: Replacing fuel tank
PostPosted: 27 Jan 2019 01:08 
Offline
Midshipman

Joined: 31 May 2017 22:18
Posts: 65
Location: Gulf of Mexico
I'm 99% sure my problem is a pinhole in the bottom corner. The leak is incredibly slow. We haven't noticed anything in the bilge, the wood around the chart table has been wicking it up. The boat has been sitting high and dry for 6 months. I think I'll add "pumping out the bottom of the fuel tank to my seasonal decomissioning.

I like the idea of rhino liner or something similar. I've been wondering if I should coat it in something to prevent water sitting against the aluminum. We're starting the project tomorrow - hoping it goes smoothly.


 
 Profile Email  
 
 Post subject: Re: Replacing fuel tank
PostPosted: 27 Jan 2019 10:42 
Offline
Rail Meat

Joined: 09 Dec 2018 20:57
Posts: 8
sailingsoulianis wrote:
.......
I like the idea of rhino liner or something similar. I've been wondering if I should coat it in something to prevent water sitting against the aluminum. We're starting the project tomorrow - hoping it goes smoothly.


The only issue I would see with Rhino Liner is outgassing. The rhino liner used in truck beds outgasses and its oder can last a while an open truck bed.


 
 Profile Email  
 
 Post subject: Re: Replacing fuel tank
PostPosted: 27 Jan 2019 12:12 
Offline
Skipper

Joined: 09 Aug 2017 15:35
Posts: 457
Location: Maine/USVI
Use Gluv-it. It's a "waterproof marine epoxy sealant" and it will outlast you. Do the whole tank, or at least start with the bottom and up the sides until you run out of the quart if you're going to skimp. It's $50/qt (I've seen it for a lot less) and $100/gallon. And get an aluminum tank, not stainless. Every diesel shop I've ever dealt with says AL is for diesel, stainless and monel are not. But at this moment I can't say why.


 
 Profile Email  
 
 Post subject: Re: Replacing fuel tank
PostPosted: 26 Oct 2019 19:47 
Offline
Skipper

Joined: 14 Jul 2012 20:36
Posts: 411
Here we are ready to head south from Norfolk and it looks like the fuel tank is leaking very slowly. Guess we'll deal with it Monday.

_________________
Hull #208, Puff Card
Southern Chesapeake Bay


 
 Profile Email  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 32 Posts ]  Go to page Previous  1, 2, 3, 4  Next

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 10 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Powered by phpBB © 2002, 2006 phpBB Group