Gas tank

Sancha

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Hey all, Jim here, new GW Sailfish25 owner. Project boat almost done. Question, I have a lg123gal and a sm 73gal tank. I would like to use the lg tank amidship and keep the sm one (? empty) to reduce unwanted weight. Any advice, good or bad. Best way to keep the tank good in FL. Thanks for any advice
 

seasick

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You have to experiment to see if the boat handles as you want it to. Sometimes the extra weight forward improves the ride and handling by lowering the bow. It may turn out that having half a tank main and half a tank aux offers better handling in your typical seas. There is no issue leaving a tank empty but note that an 'empty' tank ( as when you run on it till the motor dies) will still have some gas in it and if you don't use it and add fresh every now and then, the gas may go bad.
 

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Hey. I have the same boat. 86 Sailfish cutout transom model. Are you running twins or a single? When i had twin 200's and if running offshore i always ran the aft tank first . After 50 or 60 Gallons would switch to the main. Lots of weight back there with 75 gallons of gas,two batteries,and two persons.
 

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I agree with what Seasick mentioned, especially the dispersal or moving around of weight, as well as I'm not sure about Florida but in the Seattle area we have gasoline that has ethanol in it. If that's the case in Florida, I might leave a few gallons of fuel in the auxiliary tank as well as add some sort of fuel stabilizer as water/moisture tends to not like fuel very much. Also, replacing your fuel filters/water separators and pouring out what water might be in there will definitely help keep your gasoline fresher a bit longer. If your smaller tank truly is 73 gallons and a gallon of gasoline is 6.3lbs/gallon then that's 460lbs of added/lost weight right there, and as Seasick mentioned... that could definitely throw off the ride quality or stability of your boat. Might be worth a phone call to Grady White to see if they have any recommendations?
 
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Time Bandit

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Hey all, Jim here, new GW Sailfish25 owner. Project boat almost done. Question, I have a lg123gal and a sm 73gal tank. I would like to use the lg tank amidship and keep the sm one (? empty) to reduce unwanted weight. Any advice, good or bad. Best way to keep the tank good in FL. Thanks for any adv
 

Time Bandit

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Only use rec 90, also use yamaha ring free. About all you can do to protect the tank, also the other replies are good. I keep more fuel in the forward aux.
 

Sancha

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You have to experiment to see if the boat handles as you want it to. Sometimes the extra weight forward improves the ride and handling by lowering the bow. It may turn out that having half a tank main and half a tank aux offers better handling in your typical seas. There is no issue leaving a tank empty but note that an 'empty' tank ( as when you run on it till the motor dies) will still have some gas in it and if you don't use it and add fresh every now and then, the gas may go bad.
Thanks, my biggest concern is the potential water in the tank. If I keep just a couple of gallons in it, ( with stable ) I would think it would splash enough to coat the tank. Then just a little experimentation to address the weigh transfer.
Thanks again.
 

Sancha

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Hey. I have the same boat. 86 Sailfish cutout transom model. Are you running twins or a single? When i had twin 200's and if running offshore i always ran the aft tank first . After 50 or 60 Gallons would switch to the main. Lots of weight back there with 75 gallons of gas,two batteries,and two persons.
Very good. the past owner followed the same procedure.
I run two Yamaha's, 200's. I normally will only run 20-30 miles offshore. Shouldn't normally need all the extra fuel or weight.
This has been a project. Interior replaced, new windless, steering, trailer brakes just to name a few.
 

Sancha

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I agree with what Seasick mentioned, especially the dispersal or moving around of weight, as well as I'm not sure about Florida but in the Seattle area we have gasoline that has ethanol in it. If that's the case in Florida, I might leave a few gallons of fuel in the auxiliary tank as well as add some sort of fuel stabilizer as water/moisture tends to not like fuel very much. Also, replacing your fuel filters/water separators and pouring out what water might be in there will definitely help keep your gasoline fresher a bit longer. If your smaller tank truly is 73 gallons and a gallon of gasoline is 6.3lbs/gallon then that's 460lbs of added/lost weight right there, and as Seasick mentioned... that could definitely throw off the ride quality or stability of your boat. Might be worth a phone call to Grady White to see if they have any recommendations?
Yeah, ethanol here too. I'm hoping that as the scuppers are at the water line, the added weight removed will put her back to where she should be.
I'll keep everyone informed as this progresses.
If anyone is doing a project boat like this, I am always around to share what knowledge I have.
From chasing down water leaks to a bunch of things a retired engineer can help with.
If you get too bored I can provide a link to view the before/during and after pics as I continue.
Thanks for the warm reception and I look forward going forward with my new Grady White family.
 

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Another thought came to mind. There was always water on top of my tanks when I check the inspection holes, I put in new o rings when I purchase the boat in 1999. So I unscrewed the trim ring to find no sealer was used around them all. Water had been getting in since day one. sealed them up, now no more water. The tanks were replaced in 2015. 2002 boat.
 

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Whether you keep 2 gallons, 20 gallons or whatever in the 'other' tank, the best practice to to occasionally use and refresh tat gas to keep it fresh.
Another good idea is to keep the second tank full enough to get you home should for whatever reason the primary tank's gas becomes unusable ( like after getting a bad load of gas).
Just get used to alternating tanks every now and then and keeping some fresh gas in both.
 
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Sancha

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Another thought came to mind. There was always water on top of my tanks when I check the inspection holes, I put in new o rings when I purchase the boat in 1999. So I unscrewed the trim ring to find no sealer was used around them all. Water had been getting in since day one. sealed them up, now no more water. The tanks were replaced in 2015. 2002 boat.
Great best practice to check them. Just looking at them , you wouldn't know.
 

Sancha

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Whether you keep 2 gallons, 20 gallons or whatever in the 'other' tank, the best practice to to occasionally use and refresh tat gas to keep it fresh.
Another good idea is to keep the second tank full enough to get you home should for whatever reason the primary tank's gas becomes unusable ( like after getting a bad load of gas).
Just get used to alternating tanks every now and then and keeping some fresh gas in both.
Great advice. One that would be appreciated if/when that happens. Prevent beats response.
 

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So
its a project boat..so anything is possible..
Are you NEVER going to need that extra tank? Thats the big question.
If you sometimes want to use it then you have to use it regularly or you will end up with crap.
If you are never going to use it, think about taking it out and putting in a fish box or dry storage.

Generally, the fwd weight is going to help you. On my 265 I run the aft tank down before switching to fwd tank. I regularly FILL the fwd tank and Fill or half fill the aft tank.
I would never run with the fwd empty and the aft full. I tried it for shitzngiggles and its not good.

I don't think you will miss the aft tank one bit....unless you need more gas.
 

Sancha

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So
its a project boat..so anything is possible..
Are you NEVER going to need that extra tank? Thats the big question.
If you sometimes want to use it then you have to use it regularly or you will end up with crap.
If you are never going to use it, think about taking it out and putting in a fish box or dry storage.

Generally, the fwd weight is going to help you. On my 265 I run the aft tank down before switching to fwd tank. I regularly FILL the fwd tank and Fill or half fill the aft tank.
I would never run with the fwd empty and the aft full. I tried it for shitzngiggles and its not good.

I don't think you will miss the aft tank one bit....unless you need more gas.
Hey Skunkboat good to hear from ya. Normally won't be using it but, the is always a but, an occasional trip too the Dry Tortuga's would require the second tank for the run. I believe that with stable, leaving a couple of gallons in it will keep it coated. Then use it more and then. For normal use, the midships tank will increase performance. Thanks for your idea.
 
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ROBERTH

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I really don't get why removing the tank to reduce weight at the risk of needing fuel, etc. The weight helps with the ride. I have the 52g rear and 150g mid tank for total of 202gallons.
I go anywhere from 30 to 60 out, troll all day and run back. In a couple of cases when 40 out, seas/storm kicked in and took 2 hours to get back. Burned a lot of fuel and was glad I had the reserve as it could have gotten much worse .

As best practice, I never go out unless both tanks are full. I store both tanks full and always use Ring Free Plus and Startron to keep the water at bay. During offseason, I am usually down for about 5-6 months and so far never have any issue with fuel. Seems the Startron keeps it fresh enough to burn through safely for the first tank.

I also start off burning the aft tank down to about 48-50 gallons....the indicator light on helm flashes when it is time to switch tanks, then burn the rest on main tank. I do this to ensure once the transom fish box full of fish/ice/saltwater mix weight is offset by an empty aft tank on the way back. Kind of a tradeoff in the aft weight. Also, this helps keep the normal ride attitude in check.

Grady's like the weight and seem to ride better. I have never noticed a huge difference in fuel savings by shaving off a few pounds. I think it is minimal.
 

Sancha

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Morning Roberth, I agree. I plan on keeping the aft tank partially full with stable to continue to coat the tank. Then when needed I would just fill and use. Most of the time, I carry plenty of fuel. Now and then a longer trip will be plan needing the extra fuel.
Good comment.