Fuel Tank Capacity of 190 and 170 MONTAUK

[zenspector]

Being new to Boston Whalers: why does a 190 Montauk have a 60-gallon fuel tank and a 17 only a 12-gallon?
Thanks for any input.

[jimh]

The 170 MONTAUK uses on-deck fuel tanks; the standard set-up is to have two 6.5-gallons tanks.

The 190 MONTAUK uses a built-in below-deck fuel tank. A capacity of 60-gallons was probably chosen to make best use of the space available.

Consider the typical fuel burn rate of the engines. A 170 MONTAUK with the base 90-HP can run at cruise with a fuel consumption rate of 2.8-GPH. This means 4.2-hours endurance at cruise.

A 190 MONTAUK with the 150-HP engine can run at cruise at a fuel consumption rate of 4.2-GPH. With 55-gallons that give you 13-hours endurance.

For most owners of a 170 MONTAUK, running over four hours at cruise is probably decent endurance. A 170 is not the sort of boat you'd need to run more than 80-miles between fuel stops.

A 190 MONTAUK is a boat you can use in larger bodies of water, where more endurance is need.

If you really need more fuel endurance on the 170 MONTAUK, you can always carry an extra tank of fuel on deck. I think many owners might opt for a 20 to 24 gallon on-deck tank as their main tank. With that tank capacity, you'd be up to about 8-hours endurance at cruise. That ought to take you quite a long distance between fuel docks.

[zenspector]

Yeah, jimh, I am aware of that. I was just wondering, why such a large tank?
The way gas goes bad so quickly nowadays, and the fact that condensation raises it's ugly head with partially filled tanks, it seems a smaller capacity would make more sense. Unless, of course, one uses the boat almost daily, instead of bi-weekly to monthly as is my case.
Thanks

PS: For some reason, I only got part of your answer when I first read your response, so the rest explains a lot.
I am buying my first Whaler, a 190 with a 150 Mercury, so it is a good feeling to know I will have plenty of running time.
I was surprised at the difference when comparing it to the 17, which I first considered.

[timf]

I have a Montauk 170 with a 22 gallon tank.

http://www.easternmarine.com/moeller-22 ... k-031626br

Unless you plan on only frequent short trips, I'd recommended it for that boat.

It is more convenient and gives the option of greater ranges without needing to deal with extra fuel tanks.

Yes, like smaller tanks you need to be aware of letting the fuel get old. But with a little planning and possibly using fuel conditioner if needed, it is fairly simple to not let fuel get stale.

[jimh]

...I was just wondering, why such a large tank?

I think you are asking about the 190 MONTAUK. The tank capacity is probably a result of making use of the space available in the hull. The designers probably had a certain amount of space in the hull for a tank, and they just filled that space. That gave them the tank capacity.

Or maybe they already had a 60-gallon tank used in some other boat, and they fitted it to the 190 MONTAUK. That keeps down the number of parts in inventory.

If you look at historical fuel tank capacity in other Boston Whaler boats, you find:

OUTRAGE 18 = 63-gallon tank
OUTRAGE 19 II = 70 to 80 gallon tank (varied)
OUTRAGE 20 = 77-gallon tank
OUTRAGE 22 = 77-gallon tank
OUTRAGE 25 = 140-gallon tank

Considering today's outboard engines get much better fuel economy, I suppose you could make an argument that 60-gallons is more like 80 or 90-gallons of old. And, yes, having 13-hours of endurance is a lot of fuel capacity. But, on the other hand, you don't have to keep the tank filled to the brim all the time.

I don't see the 60-gallon tank on a 190 MONTAUK as a drawback. For one thing, if you come across a good price on fuel, you can put a lot of fuel in the tank. My truck has a 42-gallon fuel tank. It comes in handy when you find gasoline at a good price.

[jimh]

...For some reason, I only got part of your answer when I first read your response...

I probably wrote the reply in two segments.

[Jefecinco]

Over the past six years of owning a 190 Montauk I've had no fuel problems. I use Marine Sta-bil at every fill up and also add it for our very short, often nonexistent, winter season. I try to keep the tank full.

[Masbama]

My 1999 Dauntless 18 has a 65-gallon fuel tank--more than enough.

Also interesting, the 2013 brochure shows the 190 Montauk as having a 55-gallon fuel tank.