OK to move Fuel Tank forward?

[PriceTR24speed]

Any issues moving fuel tank to the front of a Jon Boat (1542)? I would like to clear out the area in front of the transom and move some weight forward to balance out the boat. I know the battery is easy, but what about the fuel tank? Here are the questions or potential issues that come to my mind.

Can my motor physically pull fuel from an extra 6-8’ away - ‘06 Merc 15hp 4 stroke?

What about fuel vapors - tank would be under the casting deck would it need to be vented?

Fuel hose shielding/protection?

Thanks

 

[TheGrandestPoobah]

as far as the pump is concerned, vertical distance from the pump is what matters, not horizontal.

 

[lckstckn2smknbrls]

I had a 12 gallon tank in the front of a 1436 with about 12' of 3/8 fuel line going to my Mariner 25 hp motor without any issues.

 

[PriceTR24speed]

Any input on the fuel tank being placed inside forward storage compartment? Any worry about gas fumes or needing ventilation?

 

[FuzzyGrub]

It can not be fully enclosed or it would be an explosion hazard. The portable tanks vent to atmosphere, and the fumes would build up in your compartment.


Before getting a bow troller in our StarCraft Mariner-V, I moved the portable 6 gal tank under the casting deck I built. It had natural ventilation though. It had an open space at the very front of the V and the back was fully open between casting and floor. The 40hp Nissan had no issues with getting gas.

The fuel hose ran along the starboard edge, out of foot traffic.

An enclosed tank will need to be hard mounted and fill and vent hoses provided and they need to meet a certain spec.

 

[PriceTR24speed]

It can not be fully enclosed or it would be an explosion hazard. The portable tanks vent to atmosphere, and the fumes would build up in your compartment.


Before getting a bow troller in our StarCraft Mariner-V, I moved the portable 6 gal tank under the casting deck I built. It had natural ventilation though. It had an open space at the very front of the V and the back was fully open between casting and floor. The 40hp Nissan had no issues with getting gas.

The fuel hose ran along the starboard edge, out of foot traffic.

An enclosed tank will need to be hard mounted and fill and vent hoses provided and they need to meet a certain spec.

Would vent louvers like these or these be enough to vent the fumes?

 

[RaisedByWolves]

Would vent louvers like these or these be enough to vent the fumes?

No, they are just perfect to let in enough oxygen for an explosion.

Any deck or floor that your tank or fuel line run through need one entire side/end open or you will need a fan.

The risks of this imo greatly outweigh the rewards.

 

[FuzzyGrub]

I don't know all the design criteria but what RBW said sounds reasonable. Not mentioned so far, is any electrical or spark generating items within the compartment are specialized or will need to be removed.

Maybe you have some mid-ship options if you need the additional weight distribution?

FWIW: Here is how mine was set-up: Mariner-V Mods

 

[airshot]

You would be OK as long as you have plenty of ventilation, many tank "lockers" have a door made from mesh to allow plenty of air acess to prevent fumes from collecting. If you boat in choppy water, keep in mind that will stir up the fumes and make the tank vent more, so some slooshing out could occur. long fuel line runs are usually not an issue unless steep verticle inclines are used. Make sure you have a good primer bulb to get that fuel moving toward that motor...

 

[airshot]

I don't know all the design criteria but what RBW said sounds reasonable. Not mentioned so far, is any electrical or spark generating items within the compartment are specialized or will need to be removed.

Maybe you have some mid-ship options if you need the additional weight distribution?

FWIW: Here is how mine was set-up: Mariner-V Mods

Cool boat, I had an 18' version of that, great boat!!

 

[Attwanl]

I moved my to under the bow seat on my 12/36. I put a hinged door in it, just open it up while launching the boat Incase of any fumes. Gave me more room in the back and distributes the weight. Leveled out the boat for a smoother ride. It really was one of the things I did that saw the biggest change on how the boat performed.

 

[Pothole]

Would vent louvers like these or these be enough to vent the fumes?

I have them on both of my boats. Very common on many of the aluminum duck boats being built today

 

[davidj65]

You would be OK as long as you have plenty of ventilation, many tank "lockers" have a door made from mesh to allow plenty of air acess to prevent fumes from collecting. If you boat in choppy water, keep in mind that will stir up the fumes and make the tank vent more, so some slooshing out could occur. long fuel line runs are usually not an issue unless steep verticle inclines are used. Make sure you have a good primer bulb to get that fuel moving toward that motor...

Is it safe to run A1 fuel lines under a floor if it is open at each end, or is this not advised?

 

[LDUBS]

Moeller makes a portable tank shaped to fit up in the pointy end of the boat.

 

[sonny1]

I like that tank a lot.

 

[airshot]

Is it safe to run A1 fuel lines under a floor if it is open at each end, or is this not advised?

Not sure about being " legal" or not, but I don't think I would do it for a long run. In some cases folks run there fuel line in the V along the side of the boat where the spray rail is formed. Fits there nicely and very visable and handy in case of an emergency. If I were to run it under the floor, I would give thought to putting the fuel line inside a pvc or other pipe just so it didn't get pinched or damaged in any way. Hopefully you will have quick connects at each end ?

 

[davidj65]

Not sure about being " legal" or not, but I don't think I would do it for a long run. In some cases folks run there fuel line in the V along the side of the boat where the spray rail is formed. Fits there nicely and very visable and handy in case of an emergency. If I were to run it under the floor, I would give thought to putting the fuel line inside a pvc or other pipe just so it didn't get pinched or damaged in any way. Hopefully you will have quick connects at each end ?

Yes, quick connects at the tank and motor. I was actually thinking of putting it in 3/4" pex pipe to protect it. A lot of folks put it along the sides, I don't really have a spray rail to tuck it under and I'd have to fasten it some way to the side, either with mechanical fasteners through the hull or epoxy clips to the hull. I definitely have to keep the fuel in the front for balance when I'm out alone, so I'm just slowly trying to find my way to a solution.

 

[Driftless]

I was actually thinking of putting it in 3/4" pex pipe to protect it

A lot of people have been using pex for conduit in both RVs and boats. It's a great idea. Bends nicely too.

 

[LaqueRatt]

What has made me hesitate to move tank and battery to the bow is the beating they'd take. I imagine the weight in the front would have a positive affect on bouncing and porpoising, but still it's going to bounce around more in the bow than it would next to the transom, eh? A bouncing fuel tank won't just release fumes, but actual gasoline. I'd rather not have raw gas slopping out. Vibration and jostling is also a good way to shorten the life of a battery. So, I'm thinking one of the often maligned hydrofoil fins would be the easiest, cheapest, and possibly smartest way to get a tail heavy tinny to behave. I've also noticed that those who install one almost all agree it was a great move. For as cheap as they are, why not give it a try? If you don't like it take it off and proceed with the plan to move tank and battery forward.

 

[airshot]

On smaller light weight boats the fins often work well, so worth a try. Just how rough is the water you boat in?? I have used fuel tanks near the front on many ocassions without issues, but I do put a piece of closed cell foam under the tank at least one inch thick and prefer 1 1/2" thick if I can find it. Where a lot of bouncing takes place I prefer metal tanks over plastic tanks as they are better sealed/ vented without making a mess. Often times if you move both battery and fuel tank amidships that will give you the balance you need and a little smoother ride for them as well. Keep in mind that anchors/ chains and rope can also help along with any tools you might carry, fire extinguishers and such can go forward with fear of to much bouncing around.