Fuel tank

[Rum_Pirate]

The aluminium fuel (petrol) tank is leaking in my twin 90hp outboard powered 22 Mako with centre console and T top.
It is located (partly) below the console which means that the seat/leaning post, T-top and the console have to be removed. $$$$

What type of tank aluminium/plastic/stainless steel/fibreglass material should I replace it?

Should I put in two tanks, ie keeping the fuel supply for each engine separate?

 

[sarabande]

is there any history of contaminated fuel in your part of the world ? If the assessment is yes. then set up two tanks, with a crossover tap, so you can select which tank to use. On any rare occasion where one tankful is dodgy, you could then switch to a clean tank. To be sure, you would have to sequentially fill each tank in turn to avoid bad fuel in both. Capacity may not be enough, though, in that case.

It gets awkward / costly then running another set of fuel lines from the crossover tap, if you want duplicated feed, to each motor.

 

[Rum_Pirate]

is there any history of contaminated fuel in your part of the world ? If the assessment is yes. then set up two tanks, with a crossover tap, so you can select which tank to use. On any rare occasion where one tankful is dodgy, you could then switch to a clean tank. To be sure, you would have to sequentially fill each tank in turn to avoid bad fuel in both. Capacity may not be enough, though, in that case.

It gets awkward / costly then running another set of fuel lines from the crossover tap, if you want duplicated feed, to each motor.

OK appreciate that great advice.

What about the type of material?

 

[Bajansailor]

I am amazed / appalled how so many boat builder will happily install an aluminium fuel tank in the bilge, such that it is resting on the hull bottom, often without any spacers to keep it above the inevitable bilge water. All sorts of potential then for all the different types of corrosion to run riot down there - and you dont notice anything happening underneath the tank until it starts leaking......
When you take it out (it does sound like a big job for sure!) I hope you will be able to find where it is leaking from.
If impressive, could you post a photo or 2 please?

I would be inclined to go for one of these welded polysomebody type tanks - I think that Rotoplastics in Trinidad will build you a custom tank suitable for fuel (as I asked them for a quote for one some years ago) even though they do not mention it as such on their website - have a look at http://www.rotoplastics.co.tt/products.asp?p=tanks.htm
Otherwise maybe look at Tek Tanks in the UK? http://www.tek-tanks.com/
Altho they do not specifically mention petrol tanks, just diesel.

 

[oldgit]

Deja vue.. nothing changes.. nothing learnt !

Nothing ever changes.My old Regal had a single alloy tank which was resting directly on the boat hull with a nice absorbant felt pad between the two.
Of course it rotted out on the bottom ,requiring the floor to be chainsawed out etc etc etc.
Would def replace with two separate plastic tanks each feeding one engine ,well remember aquiring water from somewhere in the single tank which fed both petrol engines of my old Regal ,of course then lost BOTH engines.
Fortunately there was a yacht with a nice reliable diesel to tow us back in.

 

[AndieMac]

Is there any provision for a section of the deck to be removed (unscrewed) to access the under floor fuel?

Can the console be unbolted/unscrewed or is it moulded to the deck (GRP or plywood?), and involves a major hachet job (grinders) to remove?

As the guys have said, the poly tanks will probably best suit (providing they fit in the space), and will possibly be best value price wise unless they have to be custom made.

If you are half handy, give the fibreglass a thought, mine are still perfect after 19 years. I have custom alloy aux. tanks (2 x 75 litres), but are set up above bilge water and rubber mounted.

 

[Moonshiners]

my vote for poly tanks if they can be sourced and fitted easily. otherwise, alu' - properly fitted with spacers should be fine.