Average fuel consumption while trolling

[pauljm]

Hi,

I am trying to find out how much fuel consumption everyone thinks is acceptable from a newish motor whether it be 2 stroke 4 stroke. and especially in the 5.5m to 6.5m (say 115hp to 250hp) range of boats while offshore trolling.I understand this is a broad question with many factors that influence fuel consumption but on an average can anyone tell me how much fuel they use? 10 litres per hour? 15? Thanks in advance for any responses...

[mikeh191]

Hi Payatz,my boat fishbones is 7.5m plate boat with a 100hp yamaha 4 stroke 2006 model.The best I do trolling at around 8 knots with me and 2 crew in good conditions is roughly 1 litre per nautical mile,obviously that increases with more crew,strong winds and currents.I previously had a 130hp yamaha saltwater series 2 stroke 2005 carby model which was near double the fuel comsumption of the 100hp 4 stroke.The 100hp 4 stroke is probably a little under powered for my boat but it still does 28 knots top speed. Hope this helps.

Cheers Mike

[boattart]

I just installed electronic guages and use about 4.8 litres an hour per engine. As you have acknowledged it is a broad question but I am assuming you are asking to get a rough idea of fuel reqirements for a full day I would suggest it would be safe to assume you would need less than 10 litres per hour but suggest you would want to be carrying twice that to be sure.

[a boat]

Hi, as mentioned not very specific with your boat size and engine size so a 5.5M with a 115HP clean engine will use alot less than a 6.5M with a 250HP. As a guide the Evinrude V4 troll at about 8L/hr on the right size boat when set-up right but as Burnsy said more details will help us answer that question. Simple fact is ALL clean tech engines are very similar and all are alot better than dirty engines-some by as much as 80% at low speeds, where a carby engine is at its most inefficient.

Cheers,

Huey.

[pauljm]

Hi all,

THanks for the responses...as you know Huey i have repowered my HH560SF with a 130Etec (unfortunately not through you) and am not happy with the fuel consumption which is partly to do with maybe i am underpowered?...As you know i am experimenting with props and was just trying to get a feel for what everyone else gets. I used to have a big old cruisecraft half cab 21 footer with 150hp yammy 4 stroke and could basically troll 10 plus hours with 3 ppl on board and still not use the whole 120l tank. My Haines is a few hundred kilos lighter with a 130 hp Etec and i am getting worse economy withonly 2 ppl on board.. I estimate about 13 L/Hr trying to maintain 7 to 9 knots trolling for pelagics up here on the Goldy. I am surprised to here Fishbones (hows it going mate i have now moved from sydney) response of 100hp on a 7.5m plate and still reasonably efficient....If he is getting 1 litre per nm @ 8 knots (approx) then correct me if i am wrong then once converted this equals roughly 8 litres per hour? Which is what i was hoping for out of my set up.Does anyone think this is achievable? Does anyone own a 5.5 to 6m boat and if so what economy do you get on average...i understand all the factors involved i am after average approximate consumption.Thanks again in advance.....Paul

[a boat]

Hi Paul, not sure how you thought I would of known you are the same person and as I have said before all clean tech engines on the same hull will be very similar and I see around 8-10L/hr on all the V4 I have rigged when doing 8-10knts so get yourself the right prop and go from there.

Comparing one brand of boat to the next will never be accurate and if you have I-Command that tells you accurate fuel burn per hour so not sure why you need to estimate the fuel burn at any RPM.

Cheers,

Huey.

[Dfishin]

Sorry to say mate.

Go back to the 150 hp four stroke yammy. Ive got this motor and makes me feel like i dont even have to think about fuel consumption.

In my opinion best motor for your sized boat.

Dave

[a boat]

Sorry to say mate.

Go back to the 150 hp four stroke yammy. Ive got this motor and makes me feel like i dont even have to think about fuel consumption.

In my opinion best motor for your sized boat.

Dave

Hi, that is a useful idea, I bet he does not want to spend about $20K on another outboard and as I have said before, ALL celan tech engines of the same HP use about the same amount of fuel on the same boat-which is different from one boat to the other. If you do not believe me, go to any engine website and they all have performance reports where you can often compare the same boats. Using the engine you listed on an 18 foot alloy boat that engine uses 2.2G/Hr to do 7.6M/Hr so that gives you a 3.48MPG at 2000RPM. The 150HP E-TEC on the same boat at the same RPM of 2000 is using 2.12G/hr for a speed of 9.8MPH giving a 4.6MPG usage-so better by over a mile. Yes I am sure there are other boats where the Yamaha might be better but it will be close no matter what anmd once this gentleman gets his engine propped right and at the right height he will be line ball with other clean tech engines of the same HP on this boat.

Cheers,

Huey.

PS- I just got back to work after doing a pre-delivery run on a 6.6M Plate Alloy boat with a 19 degree deadrise and weighing about a tonne (so a hard boat to push thru the water). It was powered by a 150HP E-TEC and at 8kns she was using high 7 to low 8 litres per hour depending on the current and wind. If this boat had been fitted with a V4 (130HP), which would be min HP on such a boat, the fuel burn at this same speed would of been more due to having to work harder and at this sort of speed most hulls are pushing a wall of water so not the most fuel efficent speed to drive at.

Edited December 17, 2012 by Huey @ Huett Marine

[thylacene]

FWIW 6.3m 21 degree deadrise, calm conditions, 1800kg without passengers, no wind or current to speak of. Suzuki DF175 four stroke.

1.0 litres per hour at 2 knots trolling livies

7.5 litres per hour at 7 knots trolling lures

Wind and current make a heap of difference, have seen consumption at 12 litres per hour at 7 knots with a bit of current and 15-20 knot winds.

Seldom get optimal conditions, seems the fishes prefer it a bit ordinary.

Best bet is to do some testing with your boat, set distance at cruise to establish a baseline, then same distance and 1 hour at trolling speed, and subtract consumption on first run from second this will leave the amount you used for 1 hour trolling. Whatever you come up with, double it for the purpose of estimation when working out how far and how long to provide a margin for error. Crude but effective, I don't like the thought of paddling home. If in doubt, carry extra fuel. We have a 200 litre tank, and have been out 30 odd NM and trolled for 5 hours and used 110 litres fuel, more on the way home than the way there as the weather cut up.

If your engine has NMEA, it should report point in time usage, and possibly amount used since last reset, you need a compatible gps or mfd.

Very difficult to end up with an objective comparison against different hull engine combinations as pointed out above. At best you will end up with an indicative figure, but as conditions vary so much and the impact on consumption can be almost an additional 100%, the most accurate way is to spend a day burning fuel in your rig to establish your baselines, and then compare over a number of trips until you have a level of confidence in your estimates.

Cheers

Thy

[Bentstik]

Went out yesterday chasing marlin and remembered this post,

Boat - 5.2 Webster Twinfisher

Engine - 115 yammy 2stroke 93 mod

Wind - 5 to 10 in the morning / 10 to 15 in the afternoon E/NE

Current - Nil

Trolled all day for 15 litres per hour and using 1 litre per km doing 7 knots at 2300rpm.

Buy the way we went all Zeros.

Cheers Bentstik