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Old 15 October 2011, 12:24   #11
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I do like that boat. I bet the gelcoating team were cursing you

You've thought about your "brightwork" a lot - nice wraparound handrail there. Is that Craighouse pontoon? I have unhappy memories of that....

I had guessed that you should get about 1L/Nm from those engines, if they weren't pushed over 3000rpm.
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Old 15 October 2011, 12:56   #12
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Is that Craighouse pontoon? I have unhappy memories of that....

It looks awfully familar to me too! But I have better memories of it than you I can taste the 'Jura' from here

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Old 15 October 2011, 14:21   #13
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Cheers Willk. I was running it at 3000 rpm since I got it but of late ive been trying to keep it at 25kts which is just about 26/2700 depending on the weather and how well its trimmed. Ive got a job on tomorrow morning so ill log the details of my trip and see if I can start working it out from that. (I should have been doing this from the start - I know!)
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Old 15 October 2011, 15:16   #14
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[QUOTE=willk;425491]I do like that boat. I bet the gelcoating team were cursing you

Maybe just a bit, more so with the glassfibre hardnose matched grey with the tubes. But they did a great job, and with the steelwork.
Yes Craighouse - our first trip after previous weeks launch. Glorious day - wind force 1-2, flat calm sea, sun shone all day (maybe it was all just a dream). Bit lumpier on return past Rathlin Is. to Fair Head with tide against us.

We are getting about 21/22 knots at those revs.
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Old 15 October 2011, 15:21   #15
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Pretty much the same as mine then but you have slightly more weight with the fuel you carry so its probably pretty even. Keep me posted about your consumption with the new vessel. Ive made up a spreadsheet so ill keep a note of mine and try to work it out.
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Old 15 October 2011, 15:43   #16
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I`m doing the same, only in a little black book. When i run out this tankfull, will give me a better picture. First tank we were doing engine trials and prop changes etc - so hopefully get better results.
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Old 16 October 2011, 09:41   #17
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As a rule of thumb 5 gallons per hour per 100hp used.

So, flat out, irrespective of speed, a 240hp diesel will use 12 gallons per hour.

Back off a little and this will halve.

Hope this helps as a starting point.

It's tricky just dividing fuel put in the tank by hours on the clock - you'd be surprised how much time is spent warming up / idling / pooling down the river on tickover etc and not at cruising speed.
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Old 16 October 2011, 09:48   #18
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Quote:
Originally Posted by Searider View Post
It's tricky just dividing fuel put in the tank by hours on the clock - you'd be surprised how much time is spent warming up / idling / pooling down the river on tickover etc and not at cruising speed.
This is why I prefer L/Nm at "cruising" speeds. I find it more useful for passage planning, etc.
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Old 16 October 2011, 16:19   #19
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This is why I prefer L/Nm at "cruising" speeds. I find it more useful for passage planning, etc.

Just worked out mine as 2.0 L/Nm - does that sound sensible?
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Old 16 October 2011, 16:22   #20
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Just worked out mine as 2.0 L/Nm - does that sound sensible?
Not if you're running the engine in as mentioned... I think your pencil slipped!
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