outboards-how much fuel

[gjgm]

would twin 250s be glugging in normal (silly) use ??

 

[wl745]

Twin 250s

short answer-----an awful lot.Proper answer,google the manufacturers name and look up consumption charts!!

 

[nonitoo]

A rough Google of Mercury at

http://www.mercurymarine.com/look_d...y=Title&Section=outboardChecks&sixCyl200300=4

seems to give 27 gph per engine at full chat (didn't check but that is probably US gallons) therefore, for a twin, about 56 US gph (or 212 litres/hour).

Hope my maths is correct.

Tom

 

[Nautorius]

Depends what outboards!

If they are the new Evinrude Etec 250's then they will use half as much as a 4 stroke mariner 250hp. Which engines are they?

Paul

 

[gjgm]

Yams
can you just double the number for twins.. there isnt any too significant ad/disad-vantages?
So cruising at 30knots is about 60lph, (2lpm)rising to a wallet emptying 200lph at full chat..
Thats a pretty steep curve !
Mind you, I ve never experienced any actual fuel consumption as optimistic as any manufacturer's numbers...

 

[Dave_Snelson]

YOUCH!

I was, until now, looking at one of the larger Boston Whaler cabin cruisers with twin O/B...not any more

 

[Kawasaki]

If you looking at summat with twin 250's
Well, just go for it.

Bugger the fuel.
You only live once!

 

[Kawasaki]

I was, until now, looking at one of the larger Boston Whaler cabin cruisers with twin O/B...not any more

Oh yeh?
Hmm.
Saily boat out the window?
Sorry for fred dwift folks.
But Snelson has a quandry it seems!!

 

[AndieMac]

You don't have to run outboards flat out........although they can take a lot more hard (high rev) running than 'of the shelf' inboards.

Recently had a run in a GRP offshore cruiser 23' and weighing 2500 KGS. that had the V8 outdrive (300 HP) removed and replaced with a transom pod-mounted 350 HP Yamaha 4 stroke V8.

At 3400 rpm's running at 25 knots, she was using 35 litres per hour (thats how we measure fuel consumption).

At 6100 rpm's running at 50 knots, she was using 120 litres per hour.

The (removed) outdrive (300 HP MPI Merc.) used 32 litres per hour at 21 knots, and don't have fuel figures for WOT, but would only sprint to 34 knots (Bravo 2 leg).

If you want kick-arse speed, the OB is the way to go in 'off the shelf' configurations.

 

[Moonshiners]

for comparisson (using fuel flow meter) on a Yamarin 68C
single yamaha 150hp (new 08)

5lph 5-8knts
20lph - 18-20kn
35lph - 25kn +
50lph - 40 kn + (WOT)

 

[tetleys]

Hi gjgm

Evinrude etec is the way to go, for grunt and least consumption. On our 7 metre rib we burn 1 litre per hour for each mph of speed up to 35 mph, 45 lph @ 40 mph, 55 ish @ 45, and 70 @ 52mph.

R U thinking of addition to the fleet ??

Cheers
Tetleys

 

[gjgm]

ah.. this isnt for me.
Thanks for the input everyone; I think its a toss up between you only live once, and him hating the boat bcz of the fuel costs. I think single 300 would be adequate...

 

[whisper]

"Ah this isn't for me" yeah, yeah, heard that before!!!