Fuel consumption

[jwalker]

There has been a good deal of talk about fuel consumption in the past, especially petrol v diesel. I buy my diesel in bulk and today I'm in the position to know, pretty closely, how much fuel I've consumed to date. Just for info, I thought it might be interesting to some.

8.5mtr rib, on the water typical weight 3200kg, 285hp diesel engine, overall consumption 1.1lt/mile (statute) which is a tad better than 4mpg. This includes all the running the engine has done...flushing, sitting at the quayside etc.

[codprawn]

Actually that isn't that good - the Quinquari humbers with 2x Evinrude 250s do about the same - the ONLY real advantages are the cost and availability of diesel - but they are BIG adavantages!!!

[gavin]

Thats good consumption for such a heavy boat, why not consider veg oil

once at 70 degrees it goes tro the diesel pump like diesel fuel

read articles here
http://www.dieselveg.com/

about .45 a litre

[Jono]

Originally Posted by codprawn

Actually that isn't that good - the Quinquari humbers with 2x Evinrude 250s do about the same -

Feck' off....

[Hugh Jardon]

Originally Posted by codprawn

Actually that isn't that good - the Quinquari humbers with 2x Evinrude 250s do about the same - the ONLY real advantages are the cost and availability of diesel - but they are BIG adavantages!!!

is that each engine does the same economy or combined they do the same economy, i cant imagine two 250s would average 1 lit per mile unless they are strapped to a sib

[Richard B]

In fairless to our esteemed Mr Codprawn, those are John Price's (Mr Quinquarimarine) own figures which he stated on RIB.net a little while ago, and are published in his article in the latest RIB International.

I have a feeling that there's a misunderstanding (perhaps these figures are PER ENGINE?) or is there a basic mathematical mistake? However, I've never run a 10m Humber with twin 250 Etecs, so my thoughts cannot be backed up with any evidence. JP is has stated that they are correct, and to disprove them, you would have to either inspect his acounts or work on one of his boat for a day.

[jwalker]

Originally Posted by gavin

... why not consider veg oil....
....about .45 a litre

Gavin, I'd need to be seriously green... that's about half as much again as diesel.

--------------------------
Cod, having run a Humber with 200hp, I'm with Jono. Also, remember this consumption is including the times the boat is not cruising, and, indeed, not even on the water.
-------------------------

As an extra bit of info, the figues tally almost exactly with the Volvo fuel curves for the engine. I was surprised.

[codprawn]

Originally Posted by Richard B

In fairless to our esteemed Mr Codprawn, those are John Price's (Mr Quinquarimarine) own figures which he stated on RIB.net a little while ago, and are published in his article in the latest RIB International.

I have a feeling that there's a misunderstanding (perhaps these figures are PER ENGINE?) or is there a basic mathematical mistake? However, I've never run a 10m Humber with twin 250 Etecs, so my thoughts cannot be backed up with any evidence. JP is has stated that they are correct, and to disprove them, you would have to either inspect his acounts or work on one of his boat for a day.

Exactly - I can't see why the hell John would lie about it - and he has a hell of a lot more experience than most - he really DOES know what he is talking about!!!

There is one of his boats in Swansea - they fill up from jerry cans so it can't be THAT thirsty - mine will probably need lots of trips to Tesco on a trailer!!!

[Jono]

Originally Posted by Richard B

In fairless to our esteemed Mr Codprawn, those are John Price's (Mr Quinquarimarine) own figures which he stated on RIB.net a little while ago, and are published in his article in the latest RIB International.

I have a feeling that there's a misunderstanding (perhaps these figures are PER ENGINE?) or is there a basic mathematical mistake? However, I've never run a 10m Humber with twin 250 Etecs, so my thoughts cannot be backed up with any evidence. JP is has stated that they are correct, and to disprove them, you would have to either inspect his acounts or work on one of his boat for a day.

I'll bet you believe everything that you read in the papers too? I remember when the "Daily Star" first published with the story "Lancaster found on the moon"... I ain't gonna bother going to the moon to check that out either.......

[Kernow Buoy]

"Lancaster found on the moon".

Didn't know Burt was an astronaut

[Andy Gee]

Originally Posted by codprawn

Actually that isn't that good - the Quinquari humbers with 2x Evinrude 250s do about the same - the ONLY real advantages are the cost and availability of diesel - but they are BIG adavantages!!!

Yeah and if you read the article again he also states that consumption varies by operator.
Andy

[DGR]

Just an observation - not much to back it up - but I was talking to the owner/operator of one of the 10m Humbers earlier in the summer - who were refuelling after 2 hours of running. Not sure what sort of mileage they cover, and at what sort of speeds - but they emptied a lot (8+) big jerry cans into the fuel tank. If that was just for 2 hours, I doubt that they are getting 1.1 nm/l. As I said - just an observation.

I've been running my RIB commercially all summer - and keep track of all my fuel - and I've got through 3206l in 204 hours (including some sitting at the quayside waiting/loading) and according to the odometer on the GPS, have travelled 3625 nm - slightly less than 1.2nm/l.

Having said that - a lot of the actual running is at higher than optimum cruising speed - often at or around Max Continuous revs. And I wish my quayside diesel was as cheap as JWs!!

Dylan...

[eupa]

if its any use----
my yam 250's use 60liters/hr/engine at 5100 rpm 2400 kgs gros at 55 knts.
measured by a flowscan /and empty-fill up difference at a garage petrol pump.The mimimum made at 2500 rpm and 22 knts came out at 18 liters/hr/engine- same base.

Thee are latest figures +/- 4% error and correct trim in ideal conditions.

jonathan

[Scary Des]

Originally Posted by DGR

..... I've got through 3206l ............ according to the odometer on the GPS, have travelled 3625 nm - slightly less than 1.2nm/l.
......

Dylan, I think you’ve done the sum wrong or your distance and fuel figure are the wrong way round Des

[eupa]

I've been running my RIB commercially all summer - and keep track of all my fuel - and I've got through 3206l in 204 hours (including some sitting at the quayside waiting/loading) and according to the odometer on the GPS, have travelled 3625 nm - slightly less than 1.2nm/l.

DGR that is 3206/204= 15.71 liters/hr????????????????

CANT BE RIGHT???????????? or a lot of sitting at the docks??

Jonathan

[DGR]

Originally Posted by Scary Des

Dylan, I think you’ve done the sum wrong or your distance and fuel figure are the wrong way round Des

I think that's right - 3625nm and 3206l is approx 1.2nm/l. Or the other way round is 0.83l/nm.

Originally Posted by eupa

DGR that is 3206/204= 15.71 liters/hr????????????????

CANT BE RIGHT???????????? or a lot of sitting at the docks??

Some sitting at quayside (20% max?) rest of the time switched off or driving about. I don't have an accurate figure for time at the quayside - but if I'm not going out again, after the 5 minute cool-down I turn the engine off (and the ignition!!) anyway.

As mentioned previously (on another thread) - I'm getting between 10 and 20 liters/hr (hours measured on the engine/ignition clock) depending on what we are doing.

Dylan...

[Scary Des]

Originally Posted by DGR

I think that's right - 3625nm and 3206l is approx 1.2nm/l. Or the other way round is 0.83l/nm.Dylan...

You are doing more miles than ltrs used therefore it is 0.83 which is much better than 1.2 so I’d be happy Des

[roycruse]

Originally Posted by DGR

I think that's right - 3625nm and 3206l is approx 1.2nm/l. Or the other way round is 0.83l/nm.

Des Both these figures mean exactly the same thing and are both correct you should always check what units someone is quoting before telling them that their maths is wrong.

Its like comparing (miles per gallon) with the new eurapean way of measuring cars consumption figures in (litres per 100 kilometers) The first one will have a higher value as you get more efficient and the second one will give a lower value as you get more efficient.

DGR's 1.2 nm/l is a unit that will increase with efficiency but it is exactly the same figure as 0.83l/nm which will decrease with efficiency

[DGR]

I am happy!!

[Jono]

Don't have a pop at Des.... He's got a screw loose.... and that's official !!