Approx range estimate please?

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robertt

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Hi
I am looking at an advert for a Hardy Family Pilot 20 with a 75hp Mariner Outboard. Ad says:
Engines
Engine Brand: Mariner
Engine(s) Total Power: 75 HP
Engine Type: Outboard 4S
Propeller: 3 blade propeller
Cruising Speed: 17 knots
Maximum Speed: 23 knots

Tanks
Fresh Water Tanks: (10 Liters)
Fuel Tanks: 4 (24 Liters)

My question is, can anyone give me a rough estimate of the range I could get from this boat going at speed, and going reasonably slowly?

Many thanks for your wisdom, as always!
 
Hi Neale
That was my initial reaction when I saw that description, I assumed it was something that wd make sense to those "in the know".
Surely 4x24?? I hope
 
robertt said:
Hi Neale
That was my initial reaction when I saw that description, I assumed it was something that wd make sense to those "in the know".
Surely 4x24?? I hope
Click to expand...

4 x 24 would be a lot of fuel for a boat of this size. Your range would be good with 75hp. If it does have a total of 96 litres I would guesstimate a range of about 100nm at fast cruising speeds.

The problem with 'reasonably slow' is that unless you are operating at displacement speeds (probably no more than 6 knots on this boat), the fuel bur will be worse than going at a reasonably fast, fully on the plane, speed.

At 6 knots the boats range will probably be greater than 100nm, at 10 knots it will probably be less.

If the boat turns out to have less fuel, you could probably work out a rough figure by dividing the above.

The good thing about outboards is that these tanks may well be the portable variety. If that's the case you can increase range simply by carrying another tank or two as long as you have somewhere to store it safely.
 
I only look into the Motor Boats forum occasionally and hope this reply is not too late.

For four years we owned and used an Orkney Orkadian 20 with a four stroke Yamaha 80 outboard engine. Trailing it to various locations we usually cruised between 500 and 1000 NM each year.

Our fuel consumption averaged about 1.2 litres per nautical mile. That's a genuine figure for coastal cruising, typically in Welsh and SW English waters. In flat water the boat had a maximum speed of 26 knots but sea state in our preferred areas meant we usually travelled at about 8 kts.

When we bought the boat it was 4 years old and we fitted a brand new engine. Three 25l fuel tanks came with the boat. Changing the fuel line from one tank to another was a pain, and difficult in rough water, so we had a 135l stainless steel tank fitted. For longer distances we also carried up to 60l of petrol in 10l plastic cans. I am aware that there are legal and safety reasons for not doing that but we considered the extra capacity to be valuable.

Rough water will substantially increase consumption. Allowing a sensible safety margin, we considered our range to be 100NM, i.e. 195l less a 45l reserve = 150l divided by 1.5l per NM = 100NM.

When cruising we were always aware of the desirability of refilling the cans. It made us very aware of the locations of petrol stations near to the water.

I hope these comments help.


P.S. I suggest you view the quoted Hardy performance figures with some scepticism.
 
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we usually work on 1/3 to get there, 1/3 to get back, and a 1/3 in case you've got it all wrong or the weather isn't what you expected.
If you find you are regularly ending the trip without at least a third of the fuel left you ain't taking enough.
We have on the rib, with a 90 4stroke suzuki, 90 litres in built-in tank plus two thirty litre portable tanks with change over valves. Its much easier to take a portable tank off to a garage in a friendly taxi should the need arise at a petrol less (most are where we are) marina. Really not the safest of fuels if you are cruising though !!! I'd be thinking diesel if possible.
 
robertt said:
Hi
I am looking at an advert for a Hardy Family Pilot 20 with a 75hp Mariner Outboard.
Engine(s) Total Power: 75 HP
Engine Type: Outboard 4S
Propeller: 3 blade propeller
Cruising Speed: 17 knots
Maximum Speed: 23 knots

Fuel Tanks: 4 (24 Liters)
Click to expand...


I am impressed that a single 75hp Mariner Outboard can push a Hardy Family Pilot 20 at 23 knots.

At 23 knots it would seem that the boat would be planing.
This also depends on the pitch of the prop.
I suspect it would be a 13" pitch as opposed to a 15 or 17 or 19' pitches.
http://boatpropellers.iboats.com/Yamaha-Outboard-Propellers/

This causes a tremendous range (fuel consumption) difference than a displacement hull at 23 knots.

I have a 22'0" Mako with 2 x 85hp Yamaha's with 15" pitched props

P6130007.jpg




and with two aboard (not fully loaded, it also has a 45 gallon tank) get +/- 3 miles to the imp gallon, at just above planing speed (+/-2300rpm) in relatively calm water equivalent to 0.66mile/litre.

If you work on 0.5 miles /litre you should have a fair idea.


Hardy Owners Club Forum

Hardy Pilot 20 (which engine to plane a family of 5)

From Neil Scott (No. Guest) 23 Sep 07

Hi, I am looking to buy a 1991 Hardy Pilot 20. I have a family of 5 adults and was wondering if anyone has any advice on which engine would enable this boat to plane (all 5 on board), if it is at all possible to begin with. Any comments on past experiences or just general advice would be greatly appreciated.

Many Thanks

Neil Scott

From Dominic And Nicola Gribbin (No. 2252) 23 Sep 07

I would imagine you are looking at 90hp.

5 adults will be a challenge and presents boat handling issues I would imagine at planing speeds. I would be wary.

The Pilot is only (in my humble opinion) a maximum 4 adult in comfort boat. I can only speak for sea use....But I am sure many would disagree.

We have a Honda 75hp outboard set up and a while ago, when carrying two of my inlaws and ourselves (i.e 4 in total) up the Sound Of Mull we were full throttle-flat out, with tide etc but only getting 12 knots max!

That really made us think about the Honda 90 as a future upgrade.
May make the difference when under load.
Dom.

From Gavin Brown (No. Guest) 24 Sep 07
I have a 1991 Hardy Pilot 20 with a new (07) Honda BF75.

With 5 adults on board, I have found that she will plane at about 5000 revs[ this would be Wide Open Throttle], but if all are near the stern, trim tabs are almost fully deployed to bring the nose down.

Once on the plane however there is plent power to keep her up.

I struggled with the issue of the 90 or 75, but opted for the 75 due to the new 07 model (more torque & power according to Honda), and potential insurance issues....

I suppose if you were planning to use the boat with 5 adults on a regular basis, you would be looking for a bigger engine.

Good luck
Gavin
http://www.hardy-owner.org.uk/forum/en1190551423.htm
Click to expand...
 
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