Fuel Economy
Submitted by pharlap on Mon, 2012-01-02 14:55
Hi Guys,
I have 1999 Johnson 130hp 2 stroke V4 outboard (4 Cyl) on a 5.5 mtr fibregalss runabout, what fuel economy can I expect ?
I am a newbie and had to be towed in yesterday (by a champion fella) on the Swan River after running out of fuel I had 30 ltrs of fuel on board, and ran out of fuel after about 3 hours cruising (non stop) along at say averaging 3000 RPM. I went from Tonkin Hwy boat ramp in Bassendean thru to around Perth Flying Squadron Jetty in Melville Waters, then on coming back ran out of fuel between Barrack st jetty and the Causeway.
I had been advised that approx 2000rpm is around 5 knots, and 4000rpm is approx 8 to 10 knots, when I did my skippers ticket, but does or would that depend on the outboard size HP ?
My question is what did the newbie do wrong ? (apart from running out of fuel) dhuurrr
Did I just not have enough fuel on board, for the size motor it is, for what I thought I could do ?
Or did I possibly not drive it to complement fuel economy, should I have had it up on the plane more ? Which would have had me very close to the speed limit. Would I use more fuel in this size motor going 5 to knotts, as opposed to going quicker ?
How many litres per hour should this motor use, is there a rule of thumb like 10 litres per hour, or does that again depend on how I drive it ? Or is it not that simple to work out.Doing the speed limits how long should it take me to go from Tonkin Hwy to say Fremantle fishing boat harbour ?
Thanks in advance Steve.
I have 1999 Johnson 130hp 2 stroke V4 outboard (4 Cyl) on a 5.5 mtr fibregalss runabout, what fuel economy can I expect ?
I am a newbie and had to be towed in yesterday (by a champion fella) on the Swan River after running out of fuel I had 30 ltrs of fuel on board, and ran out of fuel after about 3 hours cruising (non stop) along at say averaging 3000 RPM. I went from Tonkin Hwy boat ramp in Bassendean thru to around Perth Flying Squadron Jetty in Melville Waters, then on coming back ran out of fuel between Barrack st jetty and the Causeway.
I had been advised that approx 2000rpm is around 5 knots, and 4000rpm is approx 8 to 10 knots, when I did my skippers ticket, but does or would that depend on the outboard size HP ?
My question is what did the newbie do wrong ? (apart from running out of fuel) dhuurrr
Did I just not have enough fuel on board, for the size motor it is, for what I thought I could do ?
Or did I possibly not drive it to complement fuel economy, should I have had it up on the plane more ? Which would have had me very close to the speed limit. Would I use more fuel in this size motor going 5 to knotts, as opposed to going quicker ?
How many litres per hour should this motor use, is there a rule of thumb like 10 litres per hour, or does that again depend on how I drive it ? Or is it not that simple to work out.Doing the speed limits how long should it take me to go from Tonkin Hwy to say Fremantle fishing boat harbour ?
Thanks in advance Steve.
carnarvonite
Posts: 8669
Date Joined: 24/07/07
Distance
At a guess I would say you were getting something like 1 x km per litre. On a lot of the older two strokers we would work on approx 4 x nm to the gallon at cruising speed of 17-18 knots and halve it for anything over that figure
dodgy
Posts: 4578
Date Joined: 01/02/10
All depends on how you drive
All depends on how you drive it. Using 30l in 3 hours sounds pretty good for that configuration. Those rpms to speed dont seem to add up to me. 4000 rpm should see you planing and doing upwards of 20 knots. Maybe pack a 20l Jerry until you get your head around it.
Does anyone know where the love of god goes, when the waves turn the minutes to hours?
Feral
Posts: 1508
Date Joined: 01/11/06
I agree that your speed/rpm
I agree that your speed/rpm calculations are way off .. and your running very light on fuel .. that motor would probably use 1 litre per km cruising at 3500rpm ... so your tank is maybe good for 10km (10 there and 10 back - with 1/3 in reserve ) ... even at idle its going to be thirsty ... most boats that size carry 50 - 100 liters
grayzeee
Posts: 2283
Date Joined: 09/07/09
nobody can tell you how fast
nobody can tell you how fast you'll be going at whatever revs unless they're the previous owner.
every boat will be different
always go out with a full tank , record how far you go and fuel used next time you fill up , is what i do
If I spent half as long fishing , as I do reading this bloody forum , I'd be twice the fisherman I am.
Troy Summers
Posts: 408
Date Joined: 14/08/11
Yep, Ive just got myself a
Yep, Ive just got myself a 89 5.5 Chivers cuddy with the 135 cobra, Ive got 80 litres onboard, I know its runs at about 2800rpm for 8 knots(depends on the gale force winds etc) the Gps SOG helps a heap... One thing though, Im new to boating myself, I fill up b4 each trip and carry a jerry can on board for backup... Ive noticed, even in the river, the wind makes a huge difference to how much the boat needs to work to keep up that 8 knots, and that will effect fuel economy. I think the top up and jerry can are a great idea when I dont really have any idea of how much fuel my boat will use... btw 8 knots really sucks, especially when some bugger goes screaming past ya at 25-30 knots, and I know Id cop a fine if I dare tried it!!
Happy boating mate,
Troy
carnarvonite
Posts: 8669
Date Joined: 24/07/07
Plane
Take note of the amount of bow wave you produce when you are just off the plane at around 8 knots.
If you drop back to 6.5 or 7 knots your fuel consumption will almost halve because you are not pushing a mountain of water in front and are sitting flat iand not with the bow up.
pharlap
Posts: 69
Date Joined: 02/01/12
Exactly my point Troy
I agree with you Troy, I've only just bought it, it's the second time we have taken it out and I need to get used to it I suppose.
It does have a GPS but I didn't get an instruction book with it, (I've ordered one) so I don't know how to use it yet, I couldn't exactly say how fast I was going, I was trying to just my speed by this stupid RPM calculation I had in my head, and it was hard to say cause we had many many boats wizzing past us. I couldn't have been going over the limit cause the coppers were out there and i didn't get stopped at all.
This is why it is making it difficult to work out my useage.
It's all good advice from you guys and I feel like a knobhead now, cause I can carry 70 litres on board, and also had a 20 litre "EMPTY" jerry can on board.
Anyone got any ideas how long time wise, and how many litres of fuel it may use going to Fremantle doing the speed limits ?
It was the first time I have taken out the bros in law, imagine the flack I got, not to mention now being called Captain Pugwash.
hlokk
Posts: 4290
Date Joined: 04/04/08
Much better to get stuck in
Much better to get stuck in the river with no fuel than out on the open ocean when that seabreeze has come in.
Boats, driving style, speed can all make a difference in usage. Always fully fill up until you know how much you'll use. If you fill it at the end of a trip and it started full then you know exactly how much you used as well as giving yourself the best possible chance. You can go longer and longer trips as you get a feel for how much you use. And remember the 1/3 rule (though sometimes its good to be even more cautious). With a spare jerry if you never venture farther than the jerry can take you (plus contingency like if it's too rough to plane) then you're a bit safer. Don't forget all your other safety gear and log on with sea rescue on the ocean.
As for mistakes, I'm sure we've all made some when we were new to boating. Starting out in the river is good. The important thing is to learn as much as you can, be safe and take baby steps never progressing past your skill level. The ocean can surprise you if you get complacent! Always good to offer to take some experiences skippers out too. A wealth of knowledge and experience here.
If you try to be safe and don't be an idiot you're probably better than half the skippers out on the water!
Reefmonkey
Posts: 711
Date Joined: 22/09/08
Captain pugwash,.. that
Captain pugwash,.. that sucks! all part of the learning expirience, everybody has had to start from scratch one day and running out of fuel is somethin most would have done, pretty sure i did it a few times. I remember trying to paddle my first little boat with thongs to get to the south perth foreshore and when that failed i was standing on the bow hurling a chainless anchor ten meters ahead and pulling the boat along about 50 times till we could stand on land again.
Running out of fuel or dead battery is a pretty embarrasing thing and most expirienced skippers never run out of fuel and if they do they know to lie about it and say something cool like starter motor shat it, probably the coils or hit a dolphin:)
Sussing out your GPS will be the key to working out your fuel useage. Fill your tank up to full next time and use your gps to measure your average speed, distance travelled and note mentally what rpm your mostly doing. after your trip fill the boat back to a full tank and note on the bowser how many litres your burned and do the math at home.
you may be able to google the specs on the motor and find max fuel usage, if its any help for comparison I have a 70 carby 2 stroke and specs say it burns 26lt an hour at 5500rmp, at that rmp boat does 27knots so i know at full noise i'll get a NM a litre.
Dave J.
Bluedog
Posts: 251
Date Joined: 28/07/11
I have 90hp Johno 2 Stroke
I have 90hp Johno 2 Stroke and i'd chew threw about that driving around for 3 hours. I usually get a around 1.2-1.4km per litre out on the blue and 4000rpm sees me in the mid/high 20knt range also. You can't be stingy with fuel on boats, always fill the tank, I reckon you would have about a 100L capacity. As Grayzee said, best thing to do is fill it, record your distance and fill up again. 30L might last a little while in cars but not in boats, they're thirsty buggers especially the 2 strokers! Do you have a GPS?
hlokk
Posts: 4290
Date Joined: 04/04/08
Don't forget at 5 knots 2
Don't forget at 5 knots 2 strokes aren't terribly economical either. Planing speed is obviously better economy (dist per liter)
Swan River Fisher
Posts: 877
Date Joined: 03/05/11
4000 RPM you should be
4000 RPM you should be atleast 15 knots if not more. at 4000 RPM i get around 44 km/ h. For your motor and size boat probably around 1km per litre is what you should use at optimum range 3000- 4000 RPM (give or take). Some old 2 strokes is about 800m per litre. Carry more fuel in a 25l jerry can, or buy an under floor fuel tank.
catch any fish?
Tomcat
Posts: 614
Date Joined: 24/02/11
Swan fish
You get 44kl at 4000 rpm last week you told us you get 72kl at 5000rpm must hell of a good 150 merc to get 28kph out of the last 1000 revs
Swan River Fisher
Posts: 877
Date Joined: 03/05/11
im not bull shitting mate
im not bull shitting mate
tiimmbo
Posts: 695
Date Joined: 16/08/09
I think he must be going down
I think he must be going down hill to get that last 28kph
Lamby
Posts: 3145
Date Joined: 04/08/09
LOL
LOL
Swan River Fisher
Posts: 877
Date Joined: 03/05/11
the mercs actually an A380's
the mercs actually an A380's plane engine so i can get up to 469 knots if i wish. also has noss for extra grunt and cut the boat in half so its lighter
chookc
Posts: 442
Date Joined: 07/01/10
Fuel usage and consumption
Fuel usage and consumption will very greatly the best is to record distance and used fuel for your next 10 trips... Get a good average as to what the boat uses . But always do this with a full tank until you have a good average.. I know my 250 verado 4 stroke uses on average about 1 liter for every 1.2 km's so when planning a trip i allow 1 liter per km... has always worked for me whether its on the river at 5knots upriver or 30 knots down river and all inbetween or averaging 20 knots out in the open ocean....
Must agree I spent Saturday cruising up the swan from maylands to up past garvey park and beyong all at 5 knots whilst other small and big boats had no regard for the 5knot speed limit... or distance off a moored boat rulings when I had stopped on one of the courtesy bouys....
dodgy
Posts: 4578
Date Joined: 01/02/10
Your not suggesting that all
Your not suggesting that all those guys with years of boating experience that expressed doubt in his truely spectacular figures were actually right are you?
Does anyone know where the love of god goes, when the waves turn the minutes to hours?
davidbland50
Posts: 392
Date Joined: 24/07/11
Everyone knows
that once you are up on the plane a 1000rpm can make a hell of a difference in the top end speed. My 150 sits at 8 knots at 2000rpm whereas at 4000rpm she is cruising at 30knots. I get 1.25l/knot at 3000rpm doing 23knots.
Pharlap, I connected a fuel flow meter up to my Lowrance GPS via NMEA2000. This gives me a fairly accurate reading of my fuel usage as well as how much is left in my tank.
As to your GPS, check the net to see if you can get an online manual for your model.
Wherever you go, there you are
pharlap
Posts: 69
Date Joined: 02/01/12
Thanks Guys
Thanks guys for all the advice , seems as though everything I will need to learn and know is going to be right here at Fishwrecked.
Just on Dbland50 comment re gps/sounder, I have an Eagle Seacharter 640 cDF Fish Finding Sonar and Mapping GPS.
http://www.eaglenav.com.au/Products/Fishfinder-Chartplotters/SeaCharter-642C-DF-iGPS/
If any one cares to look it up, as I said I don't have an instruction booklet yet, and have never used one.
Is it going to serve an average fishermans needs ?
It also has provision for a SD media or memory type card, I'm assuming that I purchase a mapped card that gives me perth water mapped areas, is this correct ? Or does the GPS just come up with the coordinate points I am in ?
Does anyone know of a marine place that specialises in this to get a user manual booklet, I have allready made some enquiries and have been told that Eagle are no longer made, but are somehow connected to Navman, any ideas ?
Cheers.
davey
Posts: 272
Date Joined: 17/05/07
eagle
the manual is a free download on the link you posted, just hit the downloads tab
cheers
whipasswaverunner
Posts: 181
Date Joined: 25/09/09
Hi Mate. gotto to agree
Hi Mate. gotto to agree with others about revs and aprox speed. I was on the River today and checked out my revs and speeds.
5 knots = 1100 RPM
26.7 knots = 4100 RPM
That is with 4 adults and 6 children in 6m Seafarer Victory with 200hp Opti.
barlow
Posts: 147
Date Joined: 04/01/12
16 litres belmont freo
16 litres belmont freo return.few blats at wot when allowed. got home and studied manual for gps as first time out.next time wil pay attention to distance and work out l/km. good post and good advice for all
barlow
Posts: 147
Date Joined: 04/01/12
sorry 40 4 st yammie voyager
sorry 40 4 st yammie voyager 150, explains a bit....