14' fiber, 85hp o/b, w/ 46 gallon above deck fuel tank??

Hello all, Im new to the forum. But was hoping I could get some questions answered here regarding this boat i recently purchased. Mainly STABILITY! Its a 1995 14' v hull fiberglass ski boat (4 person-60hp max), with a 1974, 85hp, Evinrude outboard. (I know, overpowered, but not my doings) My problem is this boat only gets 1 mile to the gallon @ w.o.t. and the boat only came with a 6gal tank. I just picked up this really nice 46.75 gal aluminum above deck tank that fits perfectly across my stern, dim. are 48"X15"X15". Would this tank make my boat unstable?? Or being it covers the whole stern should be ok? I know with this tank full it would add an additional 240lbs so Id have to cut a person or 2. Or is that just way too much fuel/weight to be carrying around? And btw it does have baffels inside the tank to prevent free surface effect. If this isnt that much of a problem, the tank would also serve as a great bench/seat also! Any help or opinion in this matter would be great. Thanks again

Re: 14' fiber, 85hp o/b, w/ 46 gallon above deck fuel tank??

Hi, and welcome to iboats. IMO, that boat (if you mount that tank) is an accident waiting to happen. It's already way overpowered, and putting another 300 lbs above deck, all at the stern, on such a small boat is just gonna screw the pooch.

My .02

Re: 14' fiber, 85hp o/b, w/ 46 gallon above deck fuel tank??

I agree the 46 gal tank is going to be too heavy for a 14 footer. I would tune up the motor as it shuld get better mileage that that. Also, running that motor at WOT, should be way too fast for skiing and normal cruising. When you throttle down, the mileage will go up dramatacally. You do need another 6 gal tank, however.

Re: 14' fiber, 85hp o/b, w/ 46 gallon above deck fuel tank??

Welcome to iboats.

Short answer..... not a good idea.

If it was my tank..... I would clean it and resell it quickly........ I would not even attempt to use it in that size boat.

Re: 14' fiber, 85hp o/b, w/ 46 gallon above deck fuel tank??

Ok guys, thanks alot for your info. I thought it'd be alittle over kill but me having to run 12-15 miles I thought it might work out. I guess I have a tank to sell if anyone on here might be interested haha. BTW, what is a safe speed for tubeing and such?? And do those fins to help you plain out really work??

Re: 14' fiber, 85hp o/b, w/ 46 gallon above deck fuel tank??

Pull tubes at 25MPH or less. For little kids, 15MPH is good if you can do it.

I doub't you will need a antiventilation plate fin. That boat should plane very quickly with all that power.

Re: 14' fiber, 85hp o/b, w/ 46 gallon above deck fuel tank??

nathan2012 said:

Ok guys, thanks alot for your info. I thought it'd be alittle over kill but me having to run 12-15 miles I thought it might work out. I guess I have a tank to sell if anyone on here might be interested haha. BTW, what is a safe speed for tubeing and such?? And do those fins to help you plain out really work??

Click to expand...

I'm a great advocate of fins - best thing since sliced bread and I wouldn't own a boat without one.

Butttttttt, in your case it would be highly dangerous to put a fin on that rig. That little boat might just dig in and do a tumble. The best thing you could do is get rid of that motor. No matter who's doing it was it will be you that will have to answer for the accident.

In the interim, if you just keep the throttle below half, you'll do a lot to solve your fuel consumption issue. It might take you a bit longer to get there, but at least you might get there in one piece!

Re: 14' fiber, 85hp o/b, w/ 46 gallon above deck fuel tank??



Here is a 14 footer with a 90 and this is what it is capable of attaining--55 MPH. Now 55 on a larger hull is not such a big deal. On this small hull it needs extreme care. Note where my 15 gallon tank is mounted. This hull uses the full 15 gallons in about 1 1/2 hours. It is what it is.

I am not normally so blunt--but--Are you out of your mind? 45 gallons? You already know the answer to your question--even if you are a noob.

Re: 14' fiber, 85hp o/b, w/ 46 gallon above deck fuel tank??

Nothing like sitting on 45 gals of fuel(using a fuel tank as a bench seat??) in an overpowered unknown 14ft boat.

Re: 14' fiber, 85hp o/b, w/ 46 gallon above deck fuel tank??

everything you are doing, or asking about doing, is wrong.