Pemanant Gas Tank Question ?

[scstar]

I need some advice

I am thinking about installing a permanant gas tank under the console of my MR180 Center Console

There is a long center beam that would have to be cut out to make room for a tank.

Is this a structural support or only for floor support ?

 

[tazrig]

Re: Pemanant Gas Tank Question ?

That looks structural to my eye. Note how it appears to brace the transom with 6 big bolts? If it were mine I wouldn't cut it.

 

[dozerII]

Re: Pemanant Gas Tank Question ?

I agree with Taz, that is the main center stringer, although where you plan to take the section is a little further than half way to the bow. You may be able to make a bulk head to join the end of the center stringer to the two side stringers to compensate. The SS models only have the side stringers have no problems with structure.

 

[scstar]

Re: Pemanant Gas Tank Question ?

From looking at pictures of other Starcraft's, I see a lot don't have the center stringer
That's what got me wondering if the center stringer is not structural

 

[dozerII]

Re: Pemanant Gas Tank Question ?

I think you will be perfectly fine if you add something like these that close of the ski locker on an SS.

 

[jbcurt00]

Re: Pemanant Gas Tank Question ?

It's also a distance problem between the 2 outer stringers, w/out the central stringer, the plywood decking has to span a MUCH wider span:

How far is it between those 2 stringers? Much more then 24", 3/4" plywood won't carry the load sufficiently, IMHO, which would be thicker then the original deck. So any parts & pieces you want to put back that were sitting directly on the deck, will need to be trimmed, or they won't align properly w/ the hull & gunwales.

If you move the existing outer stringers inbound to narrow the gap, they'll become shorter, which makes the below deck space shorter. So that further complicates the deck height problem, as it's support stringers are now lower. If you can figure out the math, you might be able to move the outer stringers inbound 'just' enough to lower the tops 1/4" and allow them to be closer together AND no raise the final finish deck height.

Depending on what tank you want to install, 20-55gal all have varying heights & widths, start w/ those dimensions for your intended tank & see what you can do. You may find that the available tanks will stick up above the height of the tops of those stringers, and you may or may not want to have a hump running from back of your console to the splashwell.

Is it impossible, no.

Don't forget you want to make sure you have access to the fuel sending unit & fill neck after you put the tank below decks. And will have to route a fill hose from the gunwale to the tank fill neck.

Post a link back to your resto thread of the MR180 here so guys can find more pix of what your working on. In that thread, I'd post a link to this thread, directing people to your tank questions thread.

good luck w/ your project

 

[roscoe]

Re: Pemanant Gas Tank Question ?

I had been thinking about an in floor tank as well.

The center floor support is just that, a floor support, not tied in to the transom knee brace on my 1981 MR.

2 problems I came up with.

1, not enough height under the floor to fit a tank.
Found a tank, 700 miles away, that might fit, but it was over 6 feet long, and seller would not ship.

2, tank would have to be directly under the center console, or more forward, so that you could cut a hole in the floor to make room for the tank fill fitting and the hose, but then there is still nowhere to route the hoses to a gunnel for the deck fill. So the deck fill would need to be on the center console itself, inside the boat. Probably the vent too.

And you can't move the tank aft of the console, or you will completely block off the channel used to route the wiring, steering and control cables.


I have decided to use a permanent tank, mounted above the floor, but under the steering console.
I do have the original steel center console, but will be building a new one, that will set over the fuel tank.
I bought a Moeller 18 gallon tank, 18x36x7".

 

[scstar]

Re: Pemanant Gas Tank Question ?

Thanks for the feedback

I've decided its way too much trouble for what it's worth.
Been checking sizes and it looks like I would have to go with a custom tank unless I got incredibly luck on ebay and find a used one the right size. There's not much room to start with and the tank has to rest on something besides the ribs, and there needs to be clearance under the deck so you are not putting pressure on the gas tank as the floor flexes due to not having the extra stringer.
I might put a permanant one under the seat, but that's something I can decide later after the floor is back on.

 

[grzzzz]

Re: Pemanant Gas Tank Question ?

Moeller (FT1826) makes one that drops right in under deck.

Grzzzz

 

[roscoe]

Re: Pemanant Gas Tank Question ?

Moeller (FT1826) makes one that drops right in under deck.

Grzzzz

View attachment 217686

Got a source to buy one of those?

Do they still make those?

 

[jbcurt00]

Re: Pemanant Gas Tank Question ?

I don't think that tank fits what scstar has planned around the center console area anyway, does it? Or at least not based on his latest post about the filler neck & etc not working out as well as he'd hoped.


I think Moeller may be retooling or modifying their tank plastic formulation. A lot of their tanks @ebay lately, all new, never installed w/ #'s that don't match up to Moeller's website tank listings. Tanks are the same size & shape, but the angle/location of the filler, sending unit or etc has changed slightly.

Before I bought a trapezoid shaped bow tank, I had a search bot 'shopping' for 1. The model # I was using came back at some point as discontinued, and then about a week later, I found that # on evil-bay & bought it delivered for much less then 1/2 retail before delivery

The search bot kept looking, just never returned any hits. A month or 2 later, it came back w/ a query:

was this the tank you were shopping for?

Same shape, filler neck had changed, & the tank had a new, totally different numbering system model #........


I think Roscoe nailed it grzzz. NLA tank.....

The FT1826 is shown as out of stock @ a lot of online suppliers & but those that have it, show it as a large rectangular tank, not a 'v' shaped belly tank.

 

[roscoe]

Re: Pemanant Gas Tank Question ?

I've been looking for a tank like grzzzz posted for at least 2 years, no one seems to make one like it any longer.



Yes, Moeller had changed many of their tanks a few years ago, and now they have changed them again.
Fill/vent/outlet locations changing, and the molded in metal outlet is being replaced with a plastic outlet.

 

[scstar]

Re: Pemanant Gas Tank Question ?

Hey Grzzzz The bow tank looks like a good idea, but it won't work on the MR because of the casting deck.
Can't find it anyway. You got me looking again and a long skinny tank along the port side of the stringer might work.
It wouldn't be centered but it would be close to the center line, found one Moeller tank that might work but I need to check

 

[barato2]

Re: Pemanant Gas Tank Question ?

one other BIG SAFETY ISSUE you need to be aware of. i was working on the same thing (tank inside center console, filler, vent on side of console) but someone more knowledgeable than me stopped me short. the filler and vent need to be outboard of the hull, so that any vapors exuded vent overboard and any spillage goes overboard, both due to USCG regs and basic safety....gas vapor is heavier than air, and your hull makes a great place to trap it. no bueno. i was not happy to have to totally re-engineer my plans but it beats blowing self up.

 

[roscoe]

Re: Pemanant Gas Tank Question ?

Good point.
I forgot to mention that although I will have the center console, it will be extended over to the port gunnel, and the tank will be placed to port. So fill and vent will be outside.
Its gonna be different, but I need a location for the cooler and some additional storage, so the tank will be on the bottom, and the storage and cooler on top.

Hate giving up the ability to walk around both sides of the console, but this stuff has to go somewhere.

 

[grzzzz]

Re: Pemanant Gas Tank Question ?

Sorry you are having a tough time finding this tank. I bought it through this blog sponsor and I still have the shipping papers so I know I gave you the number i used. If it helps the discrip is "18 gal fuel tank 50.5"L X21"W X 5.38" H, invoice #730744 placed July 30 2010. My filler hole is on the right side top deck about 4-6" from the edge and about 18' in front of the wind shield. The vent and over flow is on the outside about 3-4" from the top so over fill, vapors are outside the boat. I need to take some pics of this is anyone is interested. I could see this working on a center console but there would be some part of the hoses that you might have to step over (or cover with a low storage box.). They do run pretty close along the side of the boat. Let me know if any more info/pics would help any of you. Otherwise good luck. I certainly like the added room of not having a tank up board. That's another cooler, live well or lady on board!!

Grzzzz