Gas tank leak

[bud37]

Can you get two smaller tanks in that space easily. I ask, because if you consider the boats value, then a complete boat has more value. A US gallon of gasoline is just over 6 lbs depending on the density, so your 70 gallons weighs around 430 lbs not including the tank, so that is much less, maybe that helps your thinking here.

What is the plan for removing the tank that is there now ?....if that comes out then why can't a new tank fit right back in the same spot ?

[km1125]

Qr Bbpost .... 70 gallons translates to about 560lbs. or about 4 or so adult passengers. ...

70 gallons of gasoline would be more like 420 lbs, but you also have to figure in the weight different of a 70 gallon tank vs a 140 gallon tank.

If you could get a 70 gallon one in there past the engine, could you fit a second 70, or even two smaller (say, 60 each)?

[Matt1989Carver3807]

Qr Bbpost Can you get two smaller tanks in that space easily. I ask, because if you consider the boats value, then a complete boat has more value. A US gallon of gasoline is just over 6 lbs depending on the density, so your 70 gallons weighs around 430 lbs not including the tank, so that is much less, maybe that helps your thinking here.

What is the plan for removing the tank that is there now ?....if that comes out then why can't a new tank fit right back in the same spot ?

/ Happy to accept your 6 lbs/gallon number. Aluminum tank weight is perhaps not a concern because it is offset by the weight of the alum. stbd tank.
The problem with installing two smaller tanks is that they would have to have a pipe connection at the bottom of the tanks, otherwise they would need somewhat complicated fill and empty plumbing set up to function properly. I have not yet determined the size(s) of the smaller tanks.
As mentioned before, removing the old tank could be done by (1)moving the engine and black water tank and replacing them (2)cutting a hole in the side of the boat and repairing it or (3)cutting the tank into pieces and removing it piece by piece. Thanks for your comment.

[bud37]

I agree, multiple tanks on one side create more problems than they solve, just mentioned it for the capacity side of things....FYI, no fittings are allowed below the top of gasoline tanks......

[km1125]

Qr Bbpost .... The problem with installing two smaller tanks is that they would have to have a pipe connection at the bottom of the tanks, otherwise they would need somewhat complicated fill and empty plumbing set up to function properly. ....

You'd definitely not want to put a connection at the bottom of the tank. I was thinking an auxiliary fill and then an "a/b" valve on the feed to the engine. It is a complication but gets you back closer to the original config without having to cut the side of the boat.

[g36]

If you had 2 tanks side by side and the pickup of each tee's together and then a anti siphon valve for fuel line to engine wouldn't the draw be equal from each of the 2 small tanks? Without a a/b valve? As for filling couldn't you connect both fill tubes on the tanks together with fuel fill hose and then have one tank additional fuel fill added to connect to the deck it and then fill both from one deck fill. Lots of ideas but I think personally I would probably move engine and replace with one new tank as original. But it's great conversation and I wish you the best.

[Matt1989Carver3807]

So, in the interval it appears that here in San Diego (and perhaps elsewhere) there is a preference for removing a tank by making a hole in the hull. With the 38' Carver Aftcabin this is preferred due to the speed, cost, and complexity involved. With the Shelter Island boat yards I am told that it is almost a daily occurrence on a variety of boats.
So, it would then appear the "hole" is probably most likely at some time. The alternatives by comparison appear somewhat more untested. Thanks for your comments/assistance.

[Viper]

Hope it all works out for you. Are you getting it done this year? Keep us posted.

[Matt1989Carver3807]

Just got report of a similar gas leak from a friend who had a hole in the side gas tank replacement probably (i.e. new tank) and a fiberglass repair. This was in the LA area and I am uncertain as to the type of boat. Anyway, the cost was 18K which sounds pretty spendy. Not looking yet.

[km1125]

That sounds really high, but there might have been complications or they decided to do some other things "while they were in there" Or there might have been structural members in the way which greatly complicates the restoration. On my old boat it would have been a rather simple panel to cut through with no structural members. The toughest part really would have been the gelcoat match on the side of the hull.

You should get good measurements on your current tank and the space it's in. You might be able to find replacements that would fit even if they're a little different in capacity or dimensions, but at a much lower cost than an exact replacement. Once you find one that fits, make sure you check the fill location to see if that would be usable with where the hull fill port is.

Here is a great site to check:
https://www.greatlakesskipper.com/motor ... t=5793&p=1

if you can't find one that's a really close fit, then it might be better to just get a custom one made to the OEM specs.