27FC fuel tank size

[JeffScott92]

I have an 85 27 FC with the Nissan engine. I originally thought the fuel tank was 50 gallons. I overstepped the hours recently and ended up putting in 53 gallons when I filled up. What was the size of the original fuel tanks?

[eseyoung]

74 gal tank. An additional 1.5 gal will fit in the filler neck.

[Mark Deeser]

Jeff, my 27 has a 50 gal tank, but talked with another owner who said his was 75. I wonder if it was an option when ordering the boat new, or at some point owner had tanks replaced? My tanks are almost 29 years old, don't know if they last forever. Mark

[Jay Knoll]

My 27 has two fuel tanks just forward of the aft berths, I think 50 gallons each. I'll measure them when I get back to the boat in October. BTW there are a series of gate valves in the fuel line system I can't figure out how they should be used. Right now they are all in the open position(s).

[don123]

A-27's with the 6 cylinder Nissan have twin side tanks and I think you're correct - 50 gallons each. The longer engine/transmission extends aft into the space usually occupied by the single center mounted fuel tank used on 4 cylinder A-27's

I originally thought my boat had a single 50 gallon tank too (not sure why, maybe I read it here?) until I actually measured it and did the calculation. My tank is the original for an '84 model which came with the 4D61 and it was removed (through the aft cabin after you remove the set of drawers) cleaned, repaired and reinstalled by the previous owner, so this *should be* correct for any 4 cylinder boat. It's external dimensions are 29.75 by 15 by 38 which comes out to 16,957.5 cubic inches. Divide that by the number of cubic inches in a gallon (231) and you get 73.4 gallons - Subtract 1/4" from the above dimensions to account for the tank wall thickness (1/8th all around) and you get 71 gallons. I'd round it off and call it 70 gallons

I don't know about the claim that 1.5 gallons will fit in the filler neck. First, overfilling the tank may invite a leak around the fuel tank sender gasket and second, it would take more than 15 feet of the 1.5 inch filler hose to hold a gallon and a half, but the filler hose is only 3 or 4 feet long

On my boat, I cut a hole in the deck above the tank sender and installed a flush, chromed brass 3" screw out fitting so I have access to the tank sender - It's a handy way to clean out the tank without having to remove it from the boat. I'm installing an electronic 13 segment LED fuel gauge in my new Yanmar instrument panel with a new sender. My new instrument panel is so large there was no room left on the dash for the factory fuel gauge

Don

[JT48348]

would be more helpful with pictures!

[Panhdjoe]

Hi Jeff, I measured the tank on Kippy Gril once. Since it is rectangular and I could get a tape measure to height, width and depth I took the external measurements' subtracted 1/4 inch for the thickness of the aluminum and presto! did the math. IF MY MEMORY IS CORRECT the size was right at 60 gallons. I wish I would have written it down. It would not be hard to do it again. I think its 231 cubic inches per gallon. If that is not right would someone please jump in. Joe

[tego]

Don and Jay, I recently measured my twin tanks under the cockpit lockers and computed 43 gallons each (absolutely full) so estimated 40 each with a normal filling. This is correct according to the specs in my data sheets which came with the boat. ( My PO liked to collect articles on his boat). All the articles stated 80 gallons. I have an '87 27FC with the Nissan engine. Ben

[Panhdjoe]

Hello again, I just asked Janet and she says that her memory is 70 gallons, I read DON123's post and his dimensions ring a bell, I think he is "on the money" 70 gallons. We put over 50 gal. in a couple of times.

[jhgullett]

FWIW:

My 1985 A27SC has port and starboard tanks. They corroded and leaked due to being laid on the deck without drainage under them. Luther's Welding in Bristol RI <www.lutherswelding.com> fabricated replacements and charged $1,175 for the pair and quoted them as 52 gal. each. They were made of .125 5052 Aluminum.

Had to cut an under deck glass reinforcing beam to get the old out as the nipples stuck up. Had the new tanks made with: recessed fuel supply and return nipples, an extra baffle (longitudinal), and vertical fuel quantity sensors (in place of the lever kind). Cut ports in the deck over the sensors to access them. I have a drawing of the tanks as made up in case it would be of interest.

Luther's recommends <www.yachtsurvey.com/fueltank.htm> for discussion of proper installation and general fuel tank info.

John

[denchen]

There might be a mix of US gallons and UK gallons giving different measurements here guys.

[N4QC]

Besides the UK and US differentials for gallon equivalents, the US differentiates between liquid and dry.

US gallon liquid = 231 cu in
US gallon dry = 268.8 cu in

Happy researching,

[don123]

Evidently, the 'dry' diesel fuel takes up a bit more space

Don

[N4QC]

Suspect that extra space is needed to accommodate the accompanying dry “diesel bugs” along with the dry diesel fuel…

Have fun,

[eseyoung]

A-27's with the 6 cylinder Nissan have twin side tanks and I think you're correct - 50 gallons each. The longer engine/transmission extends aft into the space usually occupied by the single center mounted fuel tank used on 4 cylinder A-27's

I originally thought my boat had a single 50 gallon tank too (not sure why, maybe I read it here?) until I actually measured it and did the calculation. My tank is the original for an '84 model which came with the 4D61 and it was removed (through the aft cabin after you remove the set of drawers) cleaned, repaired and reinstalled by the previous owner, so this *should be* correct for any 4 cylinder boat. It's external dimensions are 29.75 by 15 by 38 which comes out to 16,957.5 cubic inches. Divide that by the number of cubic inches in a gallon (231) and you get 73.4 gallons - Subtract 1/4" from the above dimensions to account for the tank wall thickness (1/8th all around) and you get 71 gallons. I'd round it off and call it 70 gallons

I don't know about the claim that 1.5 gallons will fit in the filler neck. First, overfilling the tank may invite a leak around the fuel tank sender gasket and second, it would take more than 15 feet of the 1.5 inch filler hose to hold a gallon and a half, but the filler hose is only 3 or 4 feet long

Don

Interesting...
my former 27FC was Nissan powered with one tank. I am pretty sure (only crawled in there once) the tag on the top says 74 gallons. the first time (and only) time i filled it it took 75. Maybe this tank isn't the original?