Magnum 27 fuel tank location . . . help

[Mario L.]

In an effort to increase space below decks in a 1968 27 Sport I'm considering to move the fuel tanks to the area under the floor of the cockpit . . using fuel cells so that I don't need to do any fiberglass work.

But I need to know some more on the balance of the boat ! I see this this as a big change, and it may not be the right thing to do.

This boat presently has twin 350 hp Chevies, and for my ownership will continue as a twin SBC powered boat.

AFAIK some modified 27 Sports with single engines have tanks all the way in the rear beside the engine . . which to me would seem to be a bit stern heavy??

Thoughts, input and experiences please!

Thank you,
Mario L.

[el indio]

Originally Posted by Mario L.

In an effort to increase space below decks in a 1968 27 Sport I'm considering to move the fuel tanks to the area under the floor of the cockpit . . using fuel cells so that I don't need to do any fiberglass work.

But I need to know some more on the balance of the boat ! I see this this as a big change, and it may not be the right thing to do.

This boat presently has twin 350 hp Chevies, and for my ownership will continue as a twin SBC powered boat.

AFAIK some modified 27 Sports with single engines have tanks all the way in the rear beside the engine . . which to me would seem to be a bit stern heavy??

Thoughts, input and experiences please!

Thank you,
Mario L.

leave em where they are. c/g.

[h2oboater]

Originally Posted by Mario L.

In an effort to increase space below decks in a 1968 27 Sport I'm considering to move the fuel tanks to the area under the floor of the cockpit . . using fuel cells so that I don't need to do any fiberglass work.

But I need to know some more on the balance of the boat ! I see this this as a big change, and it may not be the right thing to do.

This boat presently has twin 350 hp Chevies, and for my ownership will continue as a twin SBC powered boat.

AFAIK some modified 27 Sports with single engines have tanks all the way in the rear beside the engine . . which to me would seem to be a bit stern heavy??

Thoughts, input and experiences please!

Thank you,
Mario L.

Most Magnum sports had bow tanks only and rode well. My Mag had both bow & center tanks because we ran longer races [80 + miles] back in the day. I did have more bow lift with the front tanks empty, but for what little room you will gain in the cabin I would not move them.

[el indio]

are they leaking around the guage?

[Mario L.]

no leaks presently . . still under the original plywood covers.
So they'll stay where they are

fwiw, someone installed a thru hull ceramic head on this boat !! way forward, I mean way forward . . I don't think a 1 year old could sit on it there!

My wife will want some form of head on the boat, and I desire a pump out head, with small holding tank, as the boat will see fresh water lake use. . . any suggestions welcomed! I must keep the lady happy . . .

I suspect these tanks are made the same way as the old Donzi tanks, tinned steel??? foamed in place? Are they prone to corrosion like all the Donzi tanks . . . ???

[HIGH LIFE]

Hi Mario, On my Sedan the gas tanks 2-50 gal are located under the cockpit floor, plus I added 2-32 gal tanks aft of these (where the motors were) and installed a floor over them. On the Sedan their is a step down and the tall cabin door opens out,the step must be app. 16" deep and goes forward app. 6' into the cabin. At the front of this the ceramic head under a fiberglass hatch, I was able to install a 15 gal. holding tank just forward of the head under the liner. No one has ever complained about missing the target!!!! Air Dog has posted pictures of a blue SEDAN that Tom Anderson ownes ( my previous boat) either on OSO or Speedwake check it out..........HIGH LIFE

[jeff1000man]

My tanks were moved to under the back seat. 2 45gal tanks.

That is probably why it just loves the rough water. CG is way back in my boat. When Jerry had it, he said they sometimes had to add ballast to the front to get it the way they wanted it.

Best way to pick up some speed in that thing is to switch to single engine set up. Once you do it, you won't go back.

Have fun with it.

Jeff

[27 MAGNUM]

I too struggled with where to put the tanks on my Sport Resto. project, my Mag. had all 4 thanks;

2) 48gal under the cabin plywood covers and
2) 48gal under the cockpit floor seat.

The tanks where alum. made by Florida Marine, and where all showing signs of corrosion. I removed all 4 tanks and replaced only 2 of them from FMT. My only mistake was the 1976 dwg.'s called out a 2-3/8" fill neck. (2" is what's more common now in hose and deck fittings)

I wasn't sure where to place the 2 new tanks, like the orig. grand master did up front in the cabin or under the cockpit floor and maybe some free speed.

I ended up deciding that Don Arronow knew what he was doing with the 27 Mag. and put them in up front under the cabin. Everyone say's that Magnums are bears and ride great, maybe the tank location is why.

As far as the head in the cabin, on a Sport you would have to cut down the center stringer to install it there. The Sedan does not have the large center stringer in the cabin like the Sports and the Starfires do. I don't think you want to cut down the main stringer to get head in the cabin... (well maybe then) I would mount a seat on a 5 gal. bucket and hold a towel up for the wife, tell her to cowboy up and rough it, the Mag is worth it.

[ChristopherL]

K.I.S.D.
"Keep It Simple Dude"

Year 2 or 3 you can put a head in the boat.... lets just get it rockin across the water in year 1.





-Chris L.

[AppSysCons]

We had put our tanks under the floor, just in front of us, under the dash, all the way to the next bulkhead wall. They did come above the floor about 8 inches, we had 95 gallons in each tank, to accommodate long races, and big power.

We choose this location since we are an offshore race boat, balance and C/G were very important. The 3 of us, stood behind the tanks, right in front of the engine compartment bulkhead wall.