Petrol V Deisel

[ian38_39]

Ok so I know this has been done before but in the post duty free era I am starting to think that for those that boat on a budget there are real savings to be made from running petrol.

Before every one shouts bah humbug my thinking is this.

I run a Sealine 310 Statesman with a couple of thirsty Volvo AQ 431 bs tucked in the back, I do probably 80% of my boating on the Norfolk Broads, at this speed if I use a gallon a day more than the equivelent diesel I would be very suprised.

At sea she likes a drink I have to admit and it can be limiting when planning a trip. On another thread about fuel duty I noticed a few replys saying that people thought more about making good use of the fuel they were burning, visiting more than one port while out, that is exactly the way we approch our sea time, while we are out we get maximum enjoyment frm each gallon by visiting a number of ports that are reasonably close together and enjoy a night or 2 in each, this means that the difference in MPG is hauled back to not a lot, given the cost of the trip in total.

If I had gone for diesel rather than petrol then the equivelent boat would have cost me 10K more, that is money I would have had to borrow and as such paid interest on, if I had been in the position of not having to borrow it would still be 10k that was not making me intrest.

I have whitnessed this year a number of instances where diesels have needed serious amounts of money spending on them, the sort of sums that could have taken me out of boating for at least a couple of years while I somehow raised the money needed to fix things. even if the worst happens and one of my lumps goes bang it will cost me £2500 to replace as opposed to the £14-15K others have had to find for equivelent diesels, ok it still hurts but it is managable.

It is a pain I know but my fuel tends to come from Asda in Jerry cans, the up side of this is I pay the same per gallon as others on the Broads are paying at the pump for Red.

My servicing is cheaper and with the onset of so much electrickery to get performance from diesel engines I beleive that my engines are now more reliable than the bulk of new diesel lumps on the market.

Some may quote safety as a major factor but if petrol was dangerous would the most litigious society in the world use mainly petrol propulsion in its boats and I don't have to go down the river in a haze of smoke listening to a serious drumming and watching my coffee vibrate.

Is it not time to take a fresh look at petrol power?

Ian

 

[hlb]

Yep, nearly anything works, if your not going any where. The only problem is if you are.

 

[hlb]

Diesels run mostly trouble free for years and years, Try and find a truck, bus or boat operator on petrol.

But yep I take the point, most lawn tractors are petrol. If yer not doing much it dont count.
But the issue, that never comes up, is that few boats Never actually go any where, or just across to the Folly inn the Solent. Just a few folk use boats and a round trip of six hundred miles was not uncomon. It ain't now.

If we are going to talk about cost of fuel, it has to be among folk that buy it and use it. Nowt to do with folk that hardly use any at all.

If were going to talk about fuel. lets talk to folk thats been to the CI's Ireland, the IOM or Scillies or Brittany. Shunting up and down the solent or some river dont count. For the odd few that actually go some place it's a Hugh cost.

 

[nonitoo]

From my point of view,

1. My marina does not supply petrol, carrying 300 ltrs in cans is not an option.
2. I go twice as far as a similar boat powered by petrol on the same tankage.
3. Diesel is still substantially cheaper than petrol
4. Hopefuly I will recover some of the initial price hike on resale.

I use about 40 ltrs diesel (about £32) for a return trip to Boulogne as opposed to 80 ltrs of petrol (about £85) - quite a price difference for a day out.

My annual average is about 150 hours useage.

As you say for river use I doubt if diesel is worth the extra cost (unless you are using the inlands waterways of France where even diesel is not readily available and so endurance is important).

Tom

 

[Nautorius]

Well I had a Regal 2860 Twin Petrol (4.3GL) firstly on Windermere, then on the Thames. Yes Twin Petrol boats do have their place. Firstly they can be very cheap to buy which means less financing cost. Second, modern petrols are very reliable and not as thirsty as your old ones. Thirdly if you are not going to cruise at over 10 knots for more than 50hrs a year I worked out it is better to go petrol.

The downside is that people are scared of Petrol in boats and Petrol availability. However I have cruised extensively with Petrol boats on the South Coast, CI's, France and the Med and always got petrol in time! Admitedly you may need to plan ahead a little. My Sportsboat is Petrol down here and I would not swop it for a diesel. However my Sailing boat is Diesel the way it should be.

Pros and Cons as always

Paul

 

[ian38_39]

HLB, as you say for those doing serious sea milage diesel is going to win but as you also say probably 90% of boats don't.

We do between 20 and 40 sea hours a year and spend the rest of the time on the rivers.

this puts us in a low milage catorgary but also far more sea miles than your average MoBo thst ventures out a couple of times a year and sits in the marina for the rest of it.

i would love to do unlimited sea miles but diesle or petrol, the cost of running a boat at sea would be prohibitive to me. Having petrol alows me to own and enjoy a reasonable size boat that still gives a few weeks out on the salt a year. That is why I said for boating on a budget petrol makes sense.

ian

 

[PowerYachtBlog]

I think it also depends the size of the boat
there is a certain length and weight for a boat where petrol is just not viable...
for me above 30-35 feet is certainly not, as said before depends the usage too
but size is just of the same importance, because the bigger it is the more you might use for long trips too

 

[DAKA]

If were going to talk about fuel. lets talk to folk thats been to the CI's Ireland, the IOM or Scillies or Brittany. Shunting up and down the solent or some river dont count. For the odd few that actually go some place it's a Hugh cost.

As it happens I was talking to a local in Guernsey on Wednesday, now bearing in mind they are on duty free fuel I was surprised they didn't view petrol as an option for pleasure cruising any more than we do. In fact he had replaced twin petrols for diesels in his 32ft boat, his words not mine "they used three times as much fuel".

Petrols in sports boats are fine for buzzing across to Yarmouth from Lymington.

Its not a cost issue as much as a range issue, I took a V8 petrol 23ft Bayliner to Le Harve, I fitted an auxiliary tank and still couldn't believe how much fuel she drank, as soon as I realised I changed to diesels.

 

[ian38_39]

4. Hopefuly I will recover some of the initial price hike on resale.

I use about 40 ltrs diesel (about £32) for a return trip to Boulogne as opposed to 80 ltrs of petrol (about £85) - quite a price difference for a day out.



As you say for river use I doubt if diesel is worth the extra cost (unless you are using the inlands waterways of France where even diesel is not readily available and so endurance is important).

Tom

The resale value is key but you will never recover the interest you paid out or lost on the extra.

Interested that you quote twice the mileage, is this in fact or supposition. In theory petrol engines are 30% less efficient than Diesel and are lighter so will save some of that 30% in weight. The lower torque does mean you have to run at higher speeds on my boat to keep her on the plane but like for like there should in theory be no more than about 25% differential mileage on a tank of fuel. Due to the diesel being cheaper then £ for £ the difference would then be 40% but surely it can't be twice the range on a tank?

Ian

 

[Chris_d]

HLB, as you say for those doing serious sea milage diesel is going to win but as you also say probably 90% of boats don't.

We do between 20 and 40 sea hours a year and spend the rest of the time on the rivers.

this puts us in a low milage catorgary but also far more sea miles than your average MoBo thst ventures out a couple of times a year and sits in the marina for the rest of it.

i would love to do unlimited sea miles but diesle or petrol, the cost of running a boat at sea would be prohibitive to me. Having petrol alows me to own and enjoy a reasonable size boat that still gives a few weeks out on the salt a year. That is why I said for boating on a budget petrol makes sense.

ian

I agree with HLB on this, you need diesel if you want to use your boat seriously at sea especialy in the UK, inland it doesn't really matter but diesel is still easier to obtain.
I'm guessing though that the real problem here, is you can't easily sell your twin petrol flybridge boat, and you need to make an argument to increase the pro's of twin petrol boats in the UK. The arguments you make all make sense but you can only sell to a limited audience of like minded people, the trouble is most people buy a boat dreaming of using it extensively. The idea of buying a boat that you will only ever cruise between local marinas, near to petrol stations in does not appeal, even if in reality this is what they end up doing even in a diesel boat. But I'm afraid a twin petrol seagoing boat is always going to be of limited appeal for all the reasons previously discussed and you will struggle to sell it.

 

[Deleted User YDKXO]

The lost interest on your extra £10k is only about £300/year if you can find anyone paying 3% pa these days. So, taking your figure of diesel engines being 25-30% more efficient, you only have to buy £1000 worth of diesel in a year (2 fill ups?) to make your money back and thats before we even mention the fact that diesel is cheaper to buy and more available. Then the real big issue is depreciation. OK if you've bought your petrol engined boat for a song but in the main, petrol engined boats depreciate more quickly than diesel engined boats so the potential for losing more money on resale is greater. And since fuel prices in the future are only going to go one way and that's up, the difference in depreciation between diesel and petrol boats will only get worse given that diesel engines are always more economical than petrol. Then there is the safety aspect, possibly as you say overstated but there's no question that petrol is far more flammable and, lastly, the range issue. You can go further on a tank of diesel and it's more available so your cruising can be more extensive
IMHO, unless you are desperate for the extra performance of petrol engines, its always a no brainer. Diesel makes more sense all round

 

[ian38_39]

As it happens I was talking to a local in Guernsey on Wednesday, now bearing in mind they are on duty free fuel I was surprised they didn't view petrol as an option for pleasure cruising any more than we do. In fact he had replaced twin petrols for diesels in his 32ft boat, his words not mine "they used three times as much fuel".

If I had just spent a fortune on changing the engines in my boat to Diesel I would need to console myself that they were using 66% less fuel but again are we talking reality or aren't I clever here.

Volvo's figure's tie up fairly well with mine in that at 3500 rpm on my engines I am Burning about 8.5 Gallons an hour on each engine. 3500rpm gives me my normal cruising speed of 21-22 knots, can anyone fill in the figures for AD41's on a 310 statesman running at the same speed on diesels?

My fuel economy works out at 1.24 miles to the gallon at cruise, I would love to know if anyone has a 310 statesman that does 3.75 miles to the gallon at the same speed.

Ian

Ian

 

[Kawasaki]

Although a Petrol Head at heart, hereabouts the nearest petrol pontoons to Me are 20 miles one way and 60 the other!
So humping the stuff would be a right bind.
Yep and as dacarak and others have mentioned the range problem is as big an issue as any.

 

[nonitoo]

Interested that you quote twice the mileage, is this in fact or supposition. In theory petrol engines are 30% less efficient than Diesel and are lighter so will save some of that 30% in weight. The lower torque does mean you have to run at higher speeds on my boat to keep her on the plane but like for like there should in theory be no more than about 25% differential mileage on a tank of fuel. Due to the diesel being cheaper then £ for £ the difference would then be 40% but surely it can't be twice the range on a tank?

Ian

Ian, I am using the figures quoted by the owner of a similar sized boat, same maker, but using a 5.3ltr petrol engine (mine is 2.8ltr diesel) in the marina. There always seems to be an increase in engine sizes when you talk of petrol in these US type boats.

I'm not trying to make anything of it other than comparing the two boats at similar speeds but with very different engines and what I have been told by the other owner.

After all, there is no way any of this boating lark makes economic sense, it all comes down to what we are individually prepared to spend for the type of boating we enjoy.

I have no reason to doubt, or make any comments upon, the figures you quote other than harbour a slight suspicion that most of the figures quoted by manufacturers seem to be achieved in absolutely ideal and specific conditions, rarely achievable in real life.

Tom

 

[PCUK]

I am about to change boats and would never consider petrol due to the lack of availabilty anywhere other than the South coast and some rivers.
Also diesel bought direct from the oil supplier is far cheaper than marina priced fuel. If you buy 1000 litres or more they are happy to deliver and if you order your home heating oil at the same time you will get both at an even lower rate.

 

[ian38_39]

I agree with HLB on this, you need diesel if you want to use your boat seriously at sea especialy in the UK, inland it doesn't really matter but diesel is still easier to obtain.
I'm guessing though that the real problem here, is you can't easily sell your twin petrol flybridge boat, and you need to make an argument to increase the pro's of twin petrol boats in the UK. The arguments you make all make sense but you can only sell to a limited audience of like minded people, the trouble is most people buy a boat dreaming of using it extensively. The idea of buying a boat that you will only ever cruise between local marinas, near to petrol stations in does not appeal, even if in reality this is what they end up doing even in a diesel boat. But I'm afraid a twin petrol seagoing boat is always going to be of limited appeal for all the reasons previously discussed and you will struggle to sell it.

Agree there are less buyers but I already have one for the boat if I want to sell.

My quandary is do I or Don't I? I am thinking of a Sealine 360 as a replacement but as I say I boat on a budget.
The boat I would be buying would be about 15 years old and at an age when engines seem to start to be rebuilt. Rebuilding a couple of engines at 8-10k a piece would take me out of boating for a considerable amount of time.

My current boat is past the age of devaluation and was bought at a good price, so the issue is not one of selling, it is one of affording to go boating. My costs are currently controlled at a level I can manage, my fear is that by moving to a boat that is cheaper to run I could well find that I can't afford a boat, Which brings me back to my initial statement that petrol really does offer a viable option for those boating on a budget.

Ian

 

[Deleted User YDKXO]

If I had just spent a fortune on changing the engines in my boat to Diesel I would need to console myself that they were using 66% less fuel but again are we talking reality or aren't I clever here.

Volvo's figure's tie up fairly well with mine in that at 3500 rpm on my engines I am Burning about 8.5 Gallons an hour on each engine. 3500rpm gives me my normal cruising speed of 21-22 knots, can anyone fill in the figures for AD41's on a 310 statesman running at the same speed on diesels?

My fuel economy works out at 1.24 miles to the gallon at cruise, I would love to know if anyone has a 310 statesman that does 3.75 miles to the gallon at the same speed.

Ian

Ian

It doesn't make financial sense throwing away 2 perfectly good petrol engines and installing 2 diesels unless the engines are shagged. Maybe that explains the 66% figure? Better to sell the petrol boat and buy another one with diesels. I once had a 305 Statesman with AD31's and it did about 2.5mpg @ 20kts. I would'n't expect a 310 with AD41's to do a whole lot worse

 

[PCUK]

I don't think it makes sense to buy a boat you can't afford to run!
I am downsizing for the above reason.

 

[ian38_39]

Tom, figures wise you are probably right as the figures quoted by Volvo are US gallons and I am using the same in Imperial Gallons but my figures are checked and we never seem to get ideal conditions. Petrol engines tend to be bigger as they are usually normally aspirated where diesels will have turbo's and superchargers to try and get decent performance from a lighter engine, the only real comparison should be Horse Power which is why I asked about AD41's being 200hp against my 205hp. The other thing is turbo's and super chargers are expensive and do fail, they are another item that does not have to be factored on a petrol boat.

I am genuinely interested in what MPG is achievable from a 310 Statesman on AD41's. As I say this is not about selling my existing boat but a real attempt to find out if I can afford a cheaper boat.

Ian

 

[ian38_39]

Mike thanks for that, if your figures are right that would mean that you were getting twice the range from your 305 than I am and also paying less than half for your Miles.

2.5 miles per gallon seems high to what I was expecting, how accurately did you check these? it is not that I am questioning your honesty it is just that it will form an important part of my calculations for a new boat.

From what I am told I can expect no better than 1 mpg for a 360 on kamd 42's. I assume due to extra weight and the inefficiency of shafts over stern drives. Even given that if you were achieving 2.5 mpg from your 305 it seems a big drop to 1 mpg on a 360.