twin engines, dual fuel tanks - how do you like to use them?

[choogenboom]

Anyone have a preference as to how to run with twin engines and two fuel tanks? Options are (A) run both on one tank until its low and switch to 2nd tank or (B) run each on its own tank. Note that my 330 has a 200 Gal tank and 150 Gal tank so going with option (B) would theoretically result in drainging the 150 Gal first and then switching to run both off the remaining 50 gallons in the 200 gallon tank. Anyone have experience in any difference in how the boat rides if you draw down both tanks at once verses drawing down each tank one at a time? Only dark side I can see is if you are not paying attention you could get down to 50 gallons of reserve before you realize it. I currently run the 200 first so I know I have enough to head home if/when I switch to the 150 gallon tank.

2nd qestion. Anyone use the Garmin GFS-10 fuel flow sensor and use it to predict tank levels? I could not find an accuracy spec for it - any idea how accurate they are? Are they a replacement for the classic in the tank level sender?

Chris

 

[bhemi]

Aft tank first

I run my aft tank until it's about 2/3 empty then switch to my main tank. I'm pretty careful about getting too far down and always head for more fuel with lots of cushion. I run the aft tank down first because my boat (Marlin) is better balanced with less weight aft. I like to keep 1/3 in it because if I have a problem on the main tank I still have enough gas left to keep moving and hopefully get home.

 

[ElyseM]

i use one tank then the other. with this e10 bs, i continue to use the tank i was on when i take on fuel (unless i've run them both pretty dry, then i run main then aux).

 

[NOTHING ELSE MATTERS]

I used to empty the aft tank on my 330, seemed it rode better with the aft tank empty.

 

[Bill_N]

I run one engine on each tank on my 265 but there's only a 10 gal difference between the 2 - (130 main & 120 aux).

Bill

 

[gradyfish22]

There si a reason they are not the same size tank, not ment to be run simulataneously by design. This does not mean it cannot be done, but most boats ride better off a particular tank then another, so for distance you want to burn the tank off that has a worse effect on economy or ride first. On my 265 the aft aux tank makes the boat ride a lot worse so I burn that off first, I like the mid main tank to stay full so I plow through waves and cut them, right nwo I have a bad fuel sende rin my main tank so it is almost empty...it rides horrible with that tank empty. I tried running off both at the same time to see what it did, it ran ok but needed more adjustment with tabs and engine trim. For your particular model being the tanks are not the same size and at some point you will run off the same tank anyways, there is no point, run one tank, then the other, it is also easier to watch one fuel tank level then bet switching between two tanks to guage what you have left. If the tanks were identical size they would benefit from running seprate so you do not cross contaiminate, but since you might end up running off the one tank in the end there is no added benefit, to me it is more of a head ache to watch 2 tanks at one time on one guage. Typically when builders plan to design a boat to have each engine run off a seperate tank they are side by side tanks so that the boat runs the same as fuel is drawn and trim angle is not adjusted throughout the burn process. Except for catermarans almost nobody anymore builds this way. Play around with your tanks and run off them different ways to see if main or aux burning first runs the best and then use that from then on.

 

[Plan Sea]

twin engines, dual fule tanks-how do you use them?

I have a Marlin that I just had the filters replaced on. I can't remember how I had the tanks set.In the past, when I put gas in it, I would have to put the same amount of gas in each tank. I never switched from one tank to the other on the dash. Does that mean I was running one motor on one tank, and the other on the other? If so is there anything wrong with that?

 

[no problem]

I use 1 tank until nearly empty, then switch to the other. This helps keep the fuel fresh. And as everyone else said it generally rides better with aft tank empty first.

 

[BobP]

If you have ethanol in SC, the less time gas stays in tank the better.
So don't let the term "aux" throw you off.

Since you have two tanks, you can also protect at least one motor from taking on a contaminated fuel load, just have to be creative with the valving and how you fill tank at station. Single tank boat are vulnerable.

 

[choogenboom]

For the moment I have settled on running one engine from the main tank and one from the aux. I rely on my fuel management gauge to keep track of how much fuel I have burned and can then calculate how much I have left. Note that I have experimentally verified the accuracy of my fuel management gauge so I know I can trust it, and its more accurate than the fuel level senders. That ensures fuel in both tanks stays fresh, and if I neglect to watch my fuel I'll get a rude reminder when one engine dies that I have 50 gallons left in the main tank.

 

[sickday]

Re: Aft tank first

I run my aft tank until it's about 2/3 empty then switch to my main tank. I'm pretty careful about getting too far down and always head for more fuel with lots of cushion. I run the aft tank down first because my boat (Marlin) is better balanced with less weight aft. I like to keep 1/3 in it because if I have a problem on the main tank I still have enough gas left to keep moving and hopefully get home[/quote

Which tank is aft? Aux or main?]

 

[megabytes]

For the moment I have settled on running one engine from the main tank and one from the aux. I rely on my fuel management gauge to keep track of how much fuel I have burned and can then calculate how much I have left. Note that I have experimentally verified the accuracy of my fuel management gauge so I know I can trust it, and its more accurate than the fuel level senders. That ensures fuel in both tanks stays fresh, and if I neglect to watch my fuel I'll get a rude reminder when one engine dies that I have 50 gallons left in the main tank.

I do this as well to keep my fuel fresh and to avoid switching on the back back from a bluewater trip.