How do you use an auxiliary fufel tank?

[bobk]

Our Series I 48MY has 105 Gal fuel in a forward centerline tank and 490 gal in the main tank aft of the engines. I tend to not run the aux tank very low because I have no idea how far down the fuel pickup tube goes. What do you think of pumping it all down to the main tank so the aux tank can get a total dose of fresh fuel once in a while. We have a priming pump that is arranged to permit this. Any downside?

Bob

 

[doc g]

If it's like mine you have to transfer the fuel to be able use it. I transfer and burn it from the main tanks and then refill all the tanks at once, every time we fill. That way you know that fuel is good all the time.........Pat

 

[bobk]

Pat, that was my thought too. We can run off the aux tank, but 105 gal doesn't go far. Guess I'll empty it via the filters to the main tank.

Bob

 

[Will]

The center tank on my 43' has the same capacity and I've run it down to about 30 gallons without any problem. My fuel system valving allows me to run one engine off of the center tank and the other plus the generator off of the main tank which I do until the center tank is about 50% full, then I switch both engines to the main tank until I take on fuel again. That keeps fresh fuel in both tanks. The problem is that you have to remember to switch tanks.
Will

 

[Jaxfishgyd]

A 105 gal center fuel tank on a 43 ?

Where does it go ?

I have the two basic tanks in the stateroom, a holding tank in the engine room and a fresh water tank under the galley. No idea where I would put a center fuel tank but wouldn't mind having the extra fuel....

 

[REBrueckner]

Refreshing your aux tank fuel once a year is a good idea. Pumping into the main tank is just fine as long as the aux tank fuel is not old and cruddy. Using an additional filter/water separator for transfer between tanks is an additional safety feature. An advantage of multiple tanks is being able to fill them at alternate times and places helping insure some clean fuel is always available.

How about using the prime pump to empty the aux tank via the supply line till suction is lost...then stick the remaining fuel to see what's left...and/or top up after suction is lost and see how much the tank will take...then you'll know how much available fuel there really is.

My 48 ft YF draws fuel down to about the 15 to 20 gallon level from the two aft 250 gal tanks. The fuel supply tube is at the stern end of the tank, so when you slow down to idle from cruise and the boat levels, fuel suction can be lost. I found that when I first had my Hatt.

My 71 series engines have primed themselves after two fuel losses just by turning over the starter a few times...no problem, mon,....Others have reported problems doing so.

 

[Jaxfishgyd]

Yupper....

Twice I have lost fuel prime on one of my 6-71N's (one time I "kinda" ran out of fuel in one tank ) and both times I just filled the primary and secondary filters (disclamer.... I had added fuel to the empty tank) and within a couple of minutes was off and running.

 

[Will]

Re: How do you use an auxiliary fuel tank?

Center fuel tanks in 1980, 43' DC
In response to JAXFISHGYD:
We have a single 250+ gallon fuel tank in the aft cabin, and 3 center-line tanks, all about 100 gallons. The aft engine room center-line tank is the auxiliary fuel tank, followed by the water tank in the forward engine room. The water tank extends into the galley where it ends, followed by the holding tank. The holding tank ends in about the middle of the forward cabin.
Will