One fuel tank or two?

[Scott T-Bird]

We have a small aluminum tank (6 gallons) mounted under our cockpit sole just forward of the steering pedestal. Our boat is a 27' Starwind with Yanmar 1GM diesel.

We sip fuel during a typical sailing season and fill the tank up on average just once per year (maybe twice during a few seasons of greater use!). That's because we take the boat for day sails and don't cruise.

For various reasons, I have considered replacing the tank for a nice new one. I believe that I have room for more tankage but am considering if I want to have one small 6 gallon tank for normal daysail use and an extra tank for longer cruises at some point in the future. We plan to move the boat in the near future where cruising opportunties will be available. The alternative would be a single tank with about double the capacity.

The reason I am considering 2 tanks is that I am concerned about fuel freshness and I thought it might work better to have a smaller tank in use for the typical daysailing activity.

Any thoughts? ... this will be a spring project in the near future, hopefully.

 

[Rick D]

You probably don't need more. Your motoring time is somewhere in the area of 12 hours, even allowing for leaving some for contingencies. A far less expensive alternative would be a five gallon jerry jug. My O'Day 27 with the same engine had, I think, a ten gallon tank. I never came close to using that capacity.

 

[PaulK]

If you're concerned about "freshness", you could burn the old stuff in your furnace or give it to a friend with a diesel powered trawler. Refill your tank, and be happy not to spend money on something you don't need.

 

[Don S/V ILLusion]

There is some merit when it comes to fuel to take the "more is always better" approach if, for no other reason, dependability. I don't imply dismissing your concern about having fresh fuel but you can always either use it over 12 months in various ways or minimize the amount left over from one season to the next. Whether you do it in one or two tanks seems to me more a matter of convenience than anything else. Even aluminum tanks eventually corrode and leak which may be another consideration.

 

[Scott T-Bird]

Yes, I've pretty much made up my mind to replace the aluminum tank anyway. I've had no leaks yet but it is 27 years old and I would rather not think about it anymore. A small increase in size will probably be my solution.

 

[Ed Schenck]

You just wrote what I was going to write, a slightly larger poly tank. My boat has a tank rated at 50 gal. but I have read that it is less. At any rate it always has old fuel. Or at least did until I sailed it to Florida. Point being that I never had any "old diesel fuel" problems, not with the 2QM20 and not with the new 3YM30. There is half a tank there now that is at least two years old. My guess is that I might have to change a filter halfway through the coming season.

 

[RAD]

My old fuel tank had no access port and I could not stop thinking about what was in the bottom of this tank and it was 12 gallons so after shopping and found a 24 gallon poly tank that would fit through openings without cutting any thing was a cheap solution and piece of mind,now as a precaution I always carry a 5 gallon diesel container of fresh fuel strapped down in the bilge so 29 gallons of fuel is a lot of hours without stopping and a jug of emergency fuel that an engine fuel line could be inserted into just in case

 

[FastOlson]

Yes, I've pretty much made up my mind to replace the aluminum tank anyway. I've had no leaks yet but it is 27 years old and I would rather not think about it anymore. A small increase in size will probably be my solution.

Age is a proper concern at 27 years. A new tank will let you have an inspection port properly installed and a sending unit for a new gauge as well. Since the last quarter of most any size tank is hard to use without it sending air down the hose to the engine in bumpy conditions, it's also nice to upsize the tank a bit.

I went thru all of this planning when I replaced the old 14 gallon tank in our boat with a custom size/shaped 19 gallon one from Coastline Tanks in Bellingham, WA. They build a good product and specialize in alum. diesel tanks.
I have some photos of the project on line -- p.m. me for the url.

L

 

[gboase]

Good timing to ask this question. I happen to be doing the same thing myself this spring. I don't use that much fuel either simply because I'm a purist and hate running the iron spinnaker.

Here's my reason for installing a MUCH larger tank this year. Fuel price! The more you can carry, the easier it is to arrange for cheaper fuel. The current estimate for fuel prices later this year are headed to $5 + and by 2013 over $8 bringing us inline with European countries.

I currently use around 10 gallons per year and I'm adding another 10 gallons for a total capacity of 20. What I don't use during the season or what becomes too old will simply be used in other machines. In the mean time I can keep it topped off anytime I see fuel at a good price.

 

[bria46]

I would be more interesting to figure out how much you spend for gas just getting to your boat by car. VS adding a second 10 gal tank!