Petrol running costs help please..

HONEYMOMMY

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Question for all you experts... How much will it cost in petrol to run this beastie. Per mile will be helpfull. :D

34' Sea Ray 340 Sundancer
Engine Brand: Mercruiser
Engine(s) Total Power: 680 HP
Engine Model: 7.4L V8 Petrol Shaft Driven

We have been out in the cold and ice on slippery pontoons looking at a couple of boats.. I am sick of seeing great ads with lovely photos then finding a heap thats lucky to be afloat when we view. I know people want to sell but they could be honest when I call. Saw a boat the other day.. made the comment it was a mess and had obviously not been cared for. The salesman agreed and said it would sell for about £6k less than asked. If I wanted to buy a boat for £6K less I would be looking at ads for boats that price for christs sake!!!!!! :mad:

Anyway... Rant over. the above boat looks interesting, but a bit concerned about petrol costs.

Help welcome. ;)
 

vandy

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with such a large boat and having petrol engines on it, it is very hard to even give you an estimate ltr/mile. If you plan to keep it on River Thames (non-tidal) your 680hp engines are very overpowered. You may only switch on one of them for slow cruising up and down the river.

Those engines (each one) burn roughly 110ltr/hr at WOT, so 220ltr/hr having both engines on. So if you want to do 32knots (37mile/hr) with both engines on you burn 220ltr! so almost 7ltr/mile at WOT. You could perhaps reduce it by half, if you go slower, and a little less if you only have one engine on.

So your best fuel consumption would be 3ltr/mile. But in reality you may burn more. A sudden acceleration, waiting behind a lock, etc. etc. all increase your fuel consumption. Just check your fuel tank capacity.

Above is my own calculation based on your HP. Below is a report on 340 Sundancer which confirms my calculations!! :)


http://www.yachtsforsale.com/yacths_listing/85.html
 

russ

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Wouldn't go near a double engined petrol boat especially 7.4 even single engine will be thirsty.
I have a single engine 5.7 v8 petrol and that will use a gallon an hour on the river but take it out coastal then thats probably 2.5 mpg.
Cheaper to buy initially but you will pay at the pump, if you can find them.

A £6K drop really depends on the original broker price. Never pay the sticker price.
 

Cashbuyer

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I think £6000 is the absolute minimum in today's market. Go for at least £10K.
The decent boats are selling but only if they are well presented and seem to offer value.
Wouldn't touch Mercruisers mainly due to supply of parts (various threads will confirm) and petrol to boot. Petrol supply limited on the river and coast. Nightmare to sell unless you get it really cheap and are prepared not to add value. Your market is very limited. On the plus side - Shafts are a bonus over outdrives (less servicing costs) and you'll have plenty of room for the money, although Europeans and Brits prefer a seperate front cabin for 34ft and I think you'll be idling along the river which can't be all that good for the V8 engines? If it's the Harleyford one at £30K then it looks like alot of boat for the money - don't try and sell in a hurry...
Agree with your comments about condition of boats - it's very frustrating and time wasting
 

oldgit

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2 x BIG Petrols.No way is this economic sense ..But..

If thats the boat you can afford then thats the boat for you,many of us started out with boats that on reflection,we really should not have touched with the afore mentioned bargepole and still bear the financial scars to prove it.
If you are seriously thinking about buying this boat or something similar,then any reservations about the feelings of both broker and seller need to be left at the door to the brokerage,it is basically a pile of unsellable plastic and aluminum suitable only for recycling and should be priced accordingly,and just hope like hell that the thing is OK mechanically,cos if the owner has realised the boat is worth peanuts,he certainly aint gonna waste money looking after it by servicing and stuff .
Just remember it will be you trying to unload the thing in few summers time and even with no buyers the thing will still be gobbling up £300 a month in marina fees,insurance, river licence,etc etc.
If you do go for this bid LOW..........other wise avoid avoid avoid.:)
 
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Chris_d

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Just to reinforce the above comments unless it is very very cheap like less than 20K and you don't mind writing off the whole amount, it would be ok for pottering up and down the river for short day trips, I believe twin 7.4's will use about 2.5-3gph even at idle. To get reasonble fuel consumption you will need to run on one engine only.

Perhaps the only twin petrol installation worth considering is a couple of small 4 cylinders, these are often attached to nice servicable 80's Fairlines and Princess's and make pleasant river boats with quiet running and no smoke.

Runaway still applies if you think you might ever do some proper boating though.
 

TrueBlue

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Please, please do try to be practical.
The boat may be pretty and make a statement. But few people on the River give a lot about whatever statements folks are making.

As it's been said petrols are a NoNo on inland waterways - the most practical reason is that there are very few places that supply it and carting Jerry cans is not practical.
Not only the fuel cost but these beasts are designed to "go for a blast" and WILL be very temperamental at river speeds.

I could go on but you won't listen.

Look for something more practical - won't be hugely pretty but will do the job. Try it for a season or two then decide - with knowledge - what you really want to do.

Thames marinas are full of glistening big boats that hardly ever venture out because they are sh*t scared that the nasty concrete locks and moorings will damage their pride and joy.

A waste. Get a banger and have some FUN. There's precious little of that around today.

Practical doesn't equal boring.

Sorry: not.
 

mlines

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I run a mercruiser engined petrol boat on both the river and sea, ok so its a single engine smaller boat but:

1. Petrol is hard to get on the river unless your home marina stocks it.

2. The engines will be idling all the time on the river, this means they can be reluctant to start on leaving a lock on a hot, summers day.

3. It will not be too expensive on the river as the idling engines are fairly economic. My single engine is below 5 litres per hour on the river, so a couple of gallons gives me a day on the river.

4. Petrol is more available on the SOUTH coast (not the other coasts)

5. If you intend to go to the coast then a pair of V8's has real whoo Hoo! factor, sliding the throttles foward and hearing the engines wind up is a wonderful (but expensive) experience.

I am afraid boats like that should be on the coast...sunglasses on, pass the last marker, hit it!

IMGP7784.JPG


imgp6584107.jpg


Still the river has its attractions...

sized_imgp6311.jpg
 

oldgit

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2. The engines will be idling all the time on the river, this means they can be reluctant to start on leaving a lock on a hot, summers day.

.


O yes ......it either stalls as you go in and desperately need to stop before hitting lock gate at end of chamber....or .....will not start when you want to leave .....or......most probably.....both.
 
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DWT

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It does depend what you want to use the boat for. If it is to be on the upper Thames you will soon get fed up with having to find fuel and the engines not liking the slow speeds.

My first boat had a petrol engine which on reflection was unusually large for the size and type of boat. Whilst it was quiet and very responsive, I was always having to fill the tank, mostly using jerry cans. I now have a Broom European with two 80hp diesels which is plenty for the river. I fill the tank once a year!
 

Lazy Days

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2. The engines will be idling all the time on the river, this means they can be reluctant to start on leaving a lock on a hot, summers day.

.


O yes ......it either stalls as you go in and desperatly want to stop before hitting lock gate at end of chamber....or .....will not start when you want to leave .....or......most probably.....both.

We've got largish petrols although not as quite as enormous as described in the OP, but I can honestly say that in the 6 years we've been on the Thames we've never had any problems at all, in locks or elsewhere, with stalling or starting in any weather. OK once we had a problem in Boulter's, but that was a bust fuel pump not a temperamental engine.

Is it because they are used regularly? Is it maintenance? Are we just super lucky? I don't know.
 

mlines

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We've got largish petrols although not as quite as enormous as described in the OP, but I can honestly say that in the 6 years we've been on the Thames we've never had any problems at all, in locks or elsewhere, with stalling or starting in any weather. OK once we had a problem in Boulter's, but that was a bust fuel pump not a temperamental engine.

Is it because they are used regularly? Is it maintenance? Are we just super lucky? I don't know.

Probably depends if they are injection or carb. Mine are carb and suffer from evaporation when hot, idle and then stopped.
 

HONEYMOMMY

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Thanks everyone, that's pretty much what I expected to hear. Just thought I would put it out there for a bit of feedback though. We know we will find the right boat for us just haven't found the right one yet big enough to sleep six and carry 3 dogs without me kicking them overboard by accident because it cramped. I am worried about buying a really old boat as you can imagine. May have to keep saving a little longer.
 

oldgit

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Two Pennies Worth in Old Money

Just a comment on "old" boats.After a few years the reliability of a boat depends entirely on the amount that is spent on servicing it and keeping it in good condition.
A common misconception frequently encountered when talking to new buyers is that old boats are going to cost you a fortune in repairs just because it is not fresh out of the showroom.
A more modern boat will probably have more "whizzy" styling and if you like that then that is the sort of boat you should buy,BUT it will not mean that because it looks new and modern it will cost you less money to run.
Unfortunately the design of modern boats has not always been for the better and most older boats were designed for practicality and ease of use where as many newer boats are sold on looks and speed first and everything else appears to come a distant second.IMHO.
 
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mlines

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I quite like the Sunseekers. If you do ever intend taking it to sea then you will find the opposite of what we have been saying about it for Thames use, i.e. is a bit under powered for the sea, getting it over the hump and planing will be slow with those engines. However should be fine for river use.
 
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