Adding a Fuel Tank-Shared Filler Neck?

[Jud Hamblett]

I have purchased an 11 gallon inboard mounted gasoline tank for my 16 foot boat to add capacity. I propose to share the filler neck, vent and ground with the other inboard tank already in the boat. Any reason I should not?

 

[Mumblerone]

Re: Adding a Fuel Tank-Shared Filler Neck?

A good question! I'll be glad to hear what others say. It is usually not done that way. Be sure both tanks are vented, overflow. What king of valve arrange will you have to shut one tank off to use the other? Will the tanks be connected; or will you change hose at tank when out of fuel? Depending on your layout you may require more piping to do what you want Vs two caps. You give up the opportunity to fill one tank at a time from different sources...least you get bad gas in both tanks. May not be a big point, but something to consider. I'd personally would go with two independent tanks with two vented caps. Just some thoughts! PS: I thought it was all sand overthere!

 

[SpinnerBait_Nut]

Re: Adding a Fuel Tank-Shared Filler Neck?

It would be difficult at the least to fix a valve to fill them separate.<br />I would mount another fill cap and then install a switch valve that lets you switch from one tank to the other.<br />I would also install another fuel gauge for that new tank.<br />This switching valve I am talking about is a manual switch and I have one on my pontoon and it works real good.<br />You just have a line from each tank going to the switch valve and one line from the valve to the engine.<br />That way if for some reason you have to remove one of the tanks, you don't mess up your whole set-up.<br />Depends on the boat as to where you would mount this valve.<br />Just my .02 worth.

 

[Jack Shellac]

Re: Adding a Fuel Tank-Shared Filler Neck?

If I had the advantage of dual tanks, I think I'd also want the advantage of having them completely independant of each other. If something was wrong in your main tank, you'd just switch over to the other one.

 

[Bondo]

Re: Adding a Fuel Tank-Shared Filler Neck?

It'll Never Work.....

 

[Jud Hamblett]

Re: Adding a Fuel Tank-Shared Filler Neck?

All, Thanks for the advice. All said, I think I will install a separate filler neck and tank switch and only share the vent between the two. <br /><br />(Yeah, Lots of sand, but lots of rough Atlantic<br />as well....over the Moroccan Med coast side the waters are calm and Gibraltar is only 10 miles across! Have to dodge lots of heavy traffic through the Strait though. ) JH