C27 Fuel Tank Decision

caguy · Dec 14, 2011

I replace my old leaky one with polypropylene tank from west marine .

caguy · Dec 15, 2011

yes it was my c27 and it was the moelar , 12 gallon and it fit in there pretty nicely.

caguy · Dec 15, 2011

It must have been a 9 gallon tank. It fits in there nicely and comes out easily. I also have room for a 5 gallon jerry can and the 4 gal dink fuel tank. I set them up with the same fittings so it I ever need to switch over to the dink tank as a reserve I can just plug it in. I mostly sail to Catallina 30 nm and use about 6 gallons round trip. That was with a 10 hp 4 stroke on a Mac 25. I expect I will use 7 gals on the C-27 with a 18 hp 2 stroke. There is plenty of room for error. I know that it is an above deck tank but the fuel compartment is sealed from the rest of the boat and is it vented.

Here is a link to the one I used. West Marine had it on sale that week for about $35.

http://www.rivermarinesupply.com/xc...3009_Moeller_9_Gallon_Portable_Fuel_Tank.html

caguy · Dec 16, 2011

I replaced my in board with a 18 HP Tohatsu.

shipwreck66 · Dec 16, 2011

AJAY, your tank already has an inspection port. Just remove the sending unit from the top, you probably need to replace it by now anyhow. This hole is about two inches across and you can stick a hose down to the bottom and pump out a gallon or so and see how it looks. Part of the unit is covered by fiberglass, use a dremel tool and cut a little piece of the glass out so you can get to all the bolts on the unit, then it's a piece of cake. New sending unit only costs about $45 from West Marine. First time in 20+ years my fuel gauge has worked. If in doubt just pump it all out and put in fresh.

caguy · Dec 16, 2011

Ajay73 said:
I just recently bought a 1980 C27. Boat has been sitting idle on its cradle for about 2 years. Tank is full of diesel. I have the Universal 5411 engine. I want to either put in an inspection port in the current stainless steel tank or replace the tank completely. To buy an inspection port it costs about $166 from one source. I would then have to cut in a hole in the current tank. I'm sure I could do this myself but if I paid someone to do this it would probably be at least $50-75 for the work. How difficult would it be to cut a hole in a stainless tank? I suppose there is a question about the condition of the current tank but no current leaks and it appears in decent condition. To buy a new aluminum tank is $320 plus $75 if I want an inspection port added. I'm leaning toward just getting the new tank.

What would you do? I know it my decision but just looking for opinions. Thanks.

If your tank is stainless then keep it. It should be in great shape. Do you have a sending unit in it? Mine did and as previously posted it can serve as an inspection port. If not then it would be worth adding one. You checked it with a magnet to see if it is stainless? If you still insist on replacing it you can throw your old one my way.

philwsailz · Dec 17, 2011

Out of curiosity. On an inboard A4 C27 when faced with a need to replace a gas tank, what prevents us from utilizing the jerry can locations and ditching the built-in tank?

My reason is that on my lake I don't have a marina/fuel dock so if I am toting anyway why not just tote the boat's tank?

Seems it would save me a lot of money if and when I do need a tank. Thoughts?

shipwreck66 · Dec 17, 2011

My marina requires everyone to fuel from them, but since they don't sell diesel I just take a couple gallons out there every couple months. I've only used about 16 gallons in the past 27 months.

philwsailz · Dec 18, 2011

The issue I perceive that could be a problem is the fact that the stock built-in tank is below the A4 carb, and will not siphon or gravity drain to the carb. Were I to plumb to a portable tank in the aft lazz I would have to design in a preventative to prevent accidental flooding and/or a spill.

shipwreck66 · Dec 20, 2011

sending unit is what transmits from tank to gauge on panel. It is normally located on top of tank, hole should be about 2.25" dia when you remove the machine screws holding it in.

caguy · Dec 21, 2011

Mine was also a fuel guage and not a sending unit. If you remove that and shine a light in through it you can look down the filler hole and vice versa.
Did you test your tank to see if it is stainless steel?

shipwreck66 · Dec 26, 2011

Says who? Been using aluminum fuel tanks in aircraft since the 30's, many are still in use. All diesel rig fuel tanks are aluminum, and they have a rough life sitting outside for decades.

jrowan · Jan 2, 2012

I agree. Aluminum is pretty tough and rustproof, but it can corrode if exposed to different metal, ie. fasteners, and water in diesel fuel could cause internal corrosion. Although in the many old boats that we've owned I've never seen one fail due to corrosion. Its usually the fuel in the tank that goes bad from lack of use. Water & sludge buildup from condensation causes engine malfunctions like clogged fuel filters & injectors, etc. I've also seen a lot more wear & corrosion in rubber fuel lines running to & from the tank & bad fitting clamps cause a lot more leaks, and these are more likely the usual suspects.

shipwreck66 · Jan 4, 2012

Nobody's telling you not to. In fact, if I were to replace that monster 18 gal I'd put in a 12, or less, as this boat will never see salt water again.