How to do fuel tests?

[Synful]

Morning guys,

With getting my boat in the next week odd, I know that I need to do fuel tests so as I can accurately gauge the range of the boat and motor and also the consumption rate for when planning trips.

Despite me searching on Google and through Ausfish; there seems to be more information than I can possibly process in terms of the results to sort through, so I figure the best way to get the info I need is to ask

Obviously the rate of consumption will vary with the amount of weight that you have on board each trip; how do you guys perform your fuel tests for a new boat or, I guess a 2nd hand boat for that matter (if different this will be of interest to other members)?

[krazyfisher]

buy a fuel flow meter go out for a short trip maybe use 50l of fuel than check the fuel vs the trip on gps than add 30% to any trip for saftey

[NAGG]

It is pretty important to know your potential usage ...... What I do is fuel the boat to the maximum (overflow) Clear / reset your trip gauge / GPS ..... Set the boat up for what would be a typical day (Crew , gear etc ) ..... & take your boat to your typical destination ...... & run your boat like you normally would for the day Then at the end of the day ... take your trip reading , refuel the boat ( take the litres used) & work your consumption out (KM or NM / Lt = Distance / lt) .... Now you have your typical fuel consumption ....... I always consider 3/4 of that to be your range (as a safety margin in case of bad weather , tides or maybe a huge catch ) ..... Nagg

PS ..... You can repeat the process & build up some knowledge under different conditions / load etc

[FNQCairns]

For your rig IMO work on 2km/L in the meantime, you should see at least or better than 3km/l if your not towing/skiing/trolling all the time. 2km/L will see you back at the ramp with fuel in reserve every time at least until you get it worked out and go with Krazyfishers good advice 1/3 left over is usually a safe reserve but if your in very close 10% will be enough being it's a 30hp.

cheers fnq

[STUIE63]

synful i always carried a 10l plastic jerry under the nose of a tinny and kept an eye on the buddy tank and only used half going out once you have used the boat for a couple of trips you will soon learn do you need another buddy or underfloor fuel or it is good the way it is .mate just get out there and have fun in the new boat.
Stuie

I agree with the 1/3 on the way out 1/3 on the way home 1/3 safety margin

[disorderly]

synful i always carried a 10l plastic jerry under the nose of a tinny

Its a good idea to always carry some spare fuel.Sometimes you may want to go a bit further than you had originally planned and oars are just no fun at all.

scott

[blaze]

Its a good idea to always carry some spare fuel.Sometimes you may want to go a bit further than you had originally planned and oars are just no fun at all.

scott

And some times you are forced to go further than intended, when you work it out allow 1/3 out, 1/3 home + 1/3 reserve and also a spare bit some where (10l jerry or simular).
cheers
blaze

[Synful]

Hey guys, thanks for all your help and advice,

I was going to keep a 20Lt jerry can at least 1/2 full with me when I went out at all times anyway.

I thought there was a standard test that was done to gauge your fuel consumption; something like 5 - 15 minutes at around 6 knots and then another similar time frame at half speed and then another period at full speed. Does anyone know of this sort of a test?

[FNQCairns]

Nah wouldn't work, most people when traveling to a new spot would like to get there at cruise (some like going fast also), then there is trolling and some short blats just for the hell of it. The uses are too variable and so is the weather, you will sip fuel in the estuarys and if it gets a bit choppy outside you will gulp it -all realtive to your engine size of coarse.
On 12L so half a tank you could come back from Green Is very easily at cruising speed in good conditions- you have a lot of range per/25L tank. A half day running around Trinity inlet could also see you use 12L but you wouldn't get much fishing done

It will not take you long to get a handle on it.


cheers fnq

[Synful]

Nah wouldn't work, most people when traveling to a new spot would like to get there at cruise (some like going fast also), then there is trolling and some short blats just for the hell of it. The uses are too variable and so is the weather, you will sip fuel in the estuarys and if it gets a bit choppy outside you will gulp it -all realtive to your engine size of coarse.
On 12L so half a tank you could come back from Green Is very easily at cruising speed in good conditions- you have a lot of range per/25L tank. A half day running around Trinity inlet could also see you use 12L but you wouldn't get much fishing done

It will not take you long to get a handle on it.


cheers fnq

Yeah I am getting the impression that a lot of it will be more of a "suck it and see" type of deal

Don't think that I'd be going over to Green Island in a 4.2m tinny though FNQ; could get a bit nasty if conditions change on the way back but good to know that the little Dory would get there and back on presumably 1 tank of fuel so long as conditions were good and I didn't floor it

All good advice guys and truly appreciated by a boating newbie!

[FNQCairns]

Hope you do get out there sometime, possibly not to Green Is but just shy of it, think there is an ugly fine or something if a tinny with fisherman touches Green Is.

I have been out there in a 4.2 a few times, it's no big deal just pick your days, be prepared to leave earlier than planned, possibly tag along with another 4.2 or boat, takes an hour minimum at an economical cruise with a 30hp, get your anchoring procedures well worked out esp retrieve and watch out for those tourist boats they can make large wakes that are a nuisance at anchor.

When you are ready of coarse, just don't exclude it yet lot's of fun at times fishing out there.

cheers fnq

[Synful]

FNQ - Just sent you a PM.

[cormorant]

For safety never carry a half full jerry can either fill it up and empty it all into your tank or buy a smaller jerry can. Half full jerrys mean the other half is the vapour and that will contain a large % of volatiles of the fuel. Half full means a lesser life for fuel as it gets aerated and oxidises quicker. Half full means on a hot day the air in nthe jerry can expand and pop the jerry. Preferably never have to transfer fuel while on the water as it can be dangerous. Tempo have some that can accept your fitting from your motor or just buy a second propper boat tank as that is your safest cheapest option and you just change over your fuel lead. Rotate the use of your tanks so you always have fresh fuel.

The manufacturer may be able to tell you the maximum fuel use by your motor at wot not just their test average they use in marketing. This could then be your worst case if you add 15% for being on and off the throttle all the time if the sea conditions are poor.

C

[tunaticer]

If you take a spare tank filled to the brim you can do your run out and back on the main tank to get your consumption rate for travelleing and the spare tank can be hooked up for your trolling to get an accurate consumption there. Often the two will be wildly different in rates.

Jack.

[GAD]

Andrew ,
I reckon that if you went to Fitzroy Island you would still have plenty to spare [ new engines are so much more economical and eco friendly] and when you get there count how many 4m or smaller tinnies are there , quite a few and with the weather the way it is , out early in the morning and back by 10 to be sure. It's how I used to go to High, Kings point and Fittzroy in the 3.7 tinnie , bit scary the first few times leaving in the dark but now I reckon beats the heat and the fishing is better at night. [ though I still hate the Mulgrave river and Russel Heads on low tides or night times as there are to many sand bars ].
Best bet is to play safe and work it out as you go .

Greg