Twin diesel vs twin petrol conundrum...

I have had both, the fuel costs on the petrol boat were noticably higher, but the biggest problem was availability. I just could not have undertaken any of the cruising I have done on the diesel boat when I had petrol as the fuel just isn't widely available outside of the hotspots like the Solent.

Ps: neither boat ever exploded. Not even the diesel one with gas :D
 
I have had both, the fuel costs on the petrol boat were noticably higher, but the biggest problem was availability. I just could not have undertaken any of the cruising I have done on the diesel boat when I had petrol as the fuel just isn't widely available outside of the hotspots like the Solent.

Ps: neither boat ever exploded. Not even the diesel one with gas :D

We couldn't have done the cruising we have had we bought the petrol version of our boat that we were offered at the time we bought our diesel one. Yes it would have been £10k cheaper to buy but we would have struggled to find the fuel.

We cruise inland, estuary and coastal and there is very little petrol to be bought other then at our marina for an over inflated price.

Friends of ours came on the short trip to Wells next the Sea with us in their petrol boat. They then spent half a day of their holiday with a taxi driver taking them to the nearest petrol station 11 miles away to fill their jerry cans. We didn't refuel until we got back to our home berth. To me that isn't viable.
 
What 'significant dangers' are these?

There are literally tens of thousands of petrol engined boats up and down the south coast and elsewhere. When was the last time you saw one spontaneously combust?

I'd be more concerned about the pressurised gas systems that so many 'safer' diesel boats are fitted with.

I never suggested that there was a chance of spontaneous combustion at all.

Are you suggesting the bulk storage of petrol is inherently safer than diesel in a sea going vessel?

http://www.ybw.com/expert-advice/petrol-vs-diesel-engines-8314
 
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This looks right up your street.. And no outdrives to worry about.

https://www.gumtree.com/p/boats-kayaks-jet-skis/pershing-33s-italian-diesel-power-boat-barcelona-spain/1215567149

$_86.JPG
 
I never suggested that there was a chance of spontaneous combustion at all.

Are you suggesting the bulk storage of petrol is inherently safer than diesel in a sea going vessel?

http://www.ybw.com/expert-advice/petrol-vs-diesel-engines-8314

No, I'm suggesting that neither are inherently unsafe, as proven by the many tens of thousands of petrol boats in the UK, and millions worldwide, that sometimes go several weeks without exploding into fireballs and wiping out the immediate area.

It's interesting that in the USA, arguably the most litigious country in the world, they'll have huge petrol engines, and often several of them. But they won't have pressurised gas systems.

I'm not trying to argue that petrol is better than diesel - I've had both and prefer the latter.

However comments like 'significant dangers of bulk petrol stowage' with reference to boats simply are not true.
 
I think the thread has drifted somewhat to the classic 'Petrol vs Diesel' discussion, which tends to assume that you are comparing identically aged/condition boats with one another - which is only ever possible for new boats.

What the OP was really asking was - 'Which is better - nearly new petrols or 30 year old diesels?'

If you have nearly new petrols the reliability (fun) and the ability to use the boat should be ok. With engines that are 30 years old, what is the probability of serious stuff going wrong and spoiling your weekend / holiday?

New D4s are about £35,000 each, plus fitting..... So, potentially a £70k bill if it all unfolds.
 
I think the thread has drifted somewhat to the classic 'Petrol vs Diesel' discussion, which tends to assume that you are comparing identically aged/condition boats with one another - which is only ever possible for new boats.

What the OP was really asking was - 'Which is better - nearly new petrols or 30 year old diesels?'

If you have nearly new petrols the reliability (fun) and the ability to use the boat should be ok. With engines that are 30 years old, what is the probability of serious stuff going wrong and spoiling your weekend / holiday?

New D4s are about £35,000 each, plus fitting..... So, potentially a £70k bill if it all unfolds.

That's a bit of a how long is a piece of string question.
 
Wow! Thanks for all the informative and (equally some humorous) replies. I didn't mean to start a bun fight on petrol vs diesel...

Ok, I have a particular boat model in mind and as alluded too in a post or two, this is a stern drive boat with old engines. I probably need to come clean in that I'm now working in the marine sector and have access to parts at reasonable discounts (also new engines, but we'll leave that one aside for the minute as I wouldn't be buying new!) I don't have a problem with petrol (other than rate of consumption) and this is readily available in cruising area (plus used to outboards).

The question was indeed more about boat A - twin diesel AQAD41 with same era stern drives for say £30K or boat B - same hull, repowered with 10 year old petrols/drives for £20K. Boat A is likely to be higher cost of maintenance due to age, but lower fuel cost, slower but much better range.

Some very useful thoughts and comments however (and an interesting boat to look at ;) ) so I'll re-read and ponder a bit more... We're probably 6 months away from funds as I need to first sell an inherited flat, but this is one of those once in a lifetime things and we'll expect to keep long term. The repowered petrol may not hang around that long and although I could raise equity on the house, I've always been of the view that I'd never finance a boat this way - even short term!
 
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I take it you are entirely comfortable with the significant dangers of bulk petrol stowage when compared to diesel fuel?
Yes. Petrol cars, petrol generator, petrol chainsaw, strimmer, etc - regularly move quantities to & fro, mix with 2-stroke etc and still have all my limbs and eyebrows! :D Have worked with electrics and electronics since I was about 7 too so amply amble to minimise risks of electrical sparks, overheats etc - and none of us smoke.

The other major factor is availability of petrol, both at your home port, and where you want to cruise to,
Yes, ample sources locally. :encouragement:

From your figures I would say you are planning to travel 1300 Nm in the year. At the mpg figures you give an allowing £1.50 a litre for petrol and £1 per litre for diesel the fuel for the petrol boat will cost almost £2.7 k a year more.
Yes, the distance is the most we would do, but that's broadly what I worked out. But, unlike service costs, we have the choice of use/don't use to suit available budget. We don't do holidays either, so the boat will be used depending on budget and dare I say, weather! (Unlike current boat however we could stay onboard even when raining etc and it will only be 15 minutes from home.)

Petrol is fine but please, not in the form of inboard sterndrives. I know your budget is tight but outboards are far better, even a single outboard will probably do better than twin inboards. What's wrong with a single diesel?
This particular model of boat is only stendrive. I'll be able to rebuild in my sleep after a few years... :p

Sounds to me you know exactly why you should not buy a petrol boat with anything larger than a seagull hanging on the stern.
No amount of pleading on here for some (any ) reason to go against your better judgement and buy a twin engined petrol will make you less aware of that nagging doubt when you sign the cheque and watch the broker/seller desperately trying to conceal their glee at having unloaded the unsellable. ?
We expect use to steadily increase so first few years will be less use due to work and other commitments, 5 years on I'll look to repower - pair of used D4's would be a nice fit...
 
If fuel cost is not an issue and performance/top speed is the priority you should go with the petrols.
 
rbcoomber - I'm pretty sure I know the boat you are referring too. Don't worry, I'm not in the market for that boat but I'm rationalising a similar equation...

Some of my posts refer to Princess 266 with 205 v6s and not the above boat.

In the RIB world I've always enjoyed the 'new (ish) engine, on an old boat' as the engine is the key element to happy, safe, fun, hassle free boating.
 
Any arguments re fuel bill (s) petrol Vs Diesel are Completly defeated by the cost of refinancing /removing equity out of your house .
Further more any perceived capital benefit ( less up front for the petrol ) is completely defeated by selling a bricks n mortar UK property asset .-- cost of dispersal -legal s + agent -= £10 k so called saving ? ( £30 D vs £20P )
Think in 5y ,10y -20y etc and roll up the lost rent as well .

So in my mind this is adding up to a chain of errors
2x petrols ---- 1is ok sub 27 ft or so
Outdrives ---- money pit !
Refinancing a house -servicing debt
Selling property -losing BTL income and capital appreciation on a zilch interest rate ecoconomies .

As you say the safety issue is the only thing I agree with you -

Don,t do it -that's my 0.02 p worth

Keep the flechers to scratch "I need a boat to get out on the water " itch fair enough we all can see that .
Use the rent ( from the inherited flat ) + the saved refinancing payments. + the saved admin fees ( refinancing -estate agent + legals etc )
To - you have guessed it --- rent a boat --- even in the Med a couple or three weeks /year .
 
Our Portofino 31 averaged about 2.5mpg with AD41s.
The price differential between Petrol and 60/40 diesel in Poole at the end of last year was about 35p per liter.
I easily spent more than the difference between petrol and diesel fuel use each year on maintenance and repairs to the AD41s and their drives over the five years of ownership. I even asked my VP mechanic if I had been unlucky, and he said for their age, no I hadn't.
I am now 12 months into owning a 17 year old Mercruiser V8 petrol engine boat. The difference to the balance of my 'boat' account is staggering!!!!

You know something... :cool: Nail+head really and the age of the AQAD41's is part of the issue - I'm very mechanically capable, but access isn't great and there will come a time (not too far away I suspect) when the 41's will follow the 40's and parts will become obsolete - and at this point, maintaining becomes a headache. I'm not in the position to repower at the moment, so a 'cheap' petrol so ubiquitous that base parts are unlikely to ever be obsolete makes some sense. Also little risk of diesel bug etc (we see a lot of fuel issues on diesels - not just bug, the quality of fuel is often poor!)

I went through exactly your scenario last year Rob, upgrading from a 21' Merry Fisher with petrol outboard to a 30' twin sports cruiser. I spent ages trying to justify petrol, as all I have ever known is petrol outboards. I failed miserably on both cost and availability.

We have now purchased our 30' sports cruiser with twin D3's, she will hopefully be home in Torquay next month, you are welcome to come round and have a look and natter over beer.

Yes indeed - I've seen the posts! Look forward to seeing in the 'GRP' so to speak... Beer is a great idea :encouragement:

Worth also noting it isn't just the risk of explosion. The carbon monoxide generated by the engines can also be a killer as sadly proved on the Broads last year.

https://www.gov.uk/maib-reports/saf...g-on-motor-cruiser-results-in-loss-of-2-lives

Petrol engines create far more Carbon Monoxide then diesel engines.

Yes - very aware of CO. All 'habitable' boats should have a CO alarm just as homes should have smoke detectors - all about raising awareness.

I found range is a big factor, that extra 1mpg takes you a lot further, and of course the range anxiety is reduced if you know you can always get fuel at the other end.
Paying the extra only hurts once with a diesel boat and it usually stays in the value of the boat, but petrol hurts every time you fill up and does rather ruin the enjoyment and stop you using the boat as often.

You know the answer really, just find the money :encouragement:
It's not just the money, TBH - although finding another 10K wouldn't be easy, it's more about those 30 y/o lumps... Real costs of ownership etc. The fuel cost difference is the easy bit. Factor in the injector pumps, turbos, etc and there's little doubt that diesel engines cost more to service and maintain than petrols. Then there's those 30 year old drives vs a pair that are <10... :nonchalance:

Single Merc V8?

Petrols make some sort of sense on smaller boats, one engine per boat.
But a twin engined V8 will sound amazing whilst shrinking your wallet every time you go out.
At least with diesels, more of the investment is up-front, which means you have an incentive to go out more.

I do get that bit, but I do like a boat to perform (missus is even more of a speed freak!), so there's also that circa 27kts vs 40+ knots... 95% of the time we're likely to either be at displacement or cruising at 20~25kts, but that other 5% 'fun factor' is where many people I know have regretted getting a bigger boat! :D

Did you get in a car this week? Over 20,000 people are killed in car crashes across the globe every week!

Been on a flight recently? Try searching for plane crashes.

Walked down stairs? A thousand people a year die falling down stairs!

http://news.bbc.co.uk/1/hi/health/790609.stm

Meanwhile, hundreds of thousands, millions probably, of petrol boats carry on year after year, quite happily managing not to go pop.

In the grand scheme of things, running a petrol boat with a modicum of care really is not taking your life in your hands.

Agree 100% the few that do go pop aren't always petrols either - there was a huge fire a couple of years ago due to a turbo on a diesel boat! GRP is pretty flammable too, but I'm not going to be looking for a concrete sportscruiser! :rolleyes:
 
You know something... :cool: Nail+head really and the age of the AQAD41's is part of the issue - I'm very mechanically capable, but access isn't great and there will come a time (not too far away I suspect) when the 41's will follow the 40's and parts will become obsolete - and at this point, maintaining becomes a headache. I'm not in the position to repower at the moment, so a 'cheap' petrol so ubiquitous that base parts are unlikely to ever be obsolete makes some sense. Also little risk of diesel bug etc (we see a lot of fuel issues on diesels - not just bug, the quality of fuel is often poor!)

In my opinion, the cost of 'servicing' the two boat will actually be very similar. You mention injection pump and turbos, but these are not what I would call 'service' items. The drives will be pretty much the same to service, and the engines will be almost the same with the diesels probably needing more oil but the petrols needing spark plugs.

The point you are trying to make is not so much servicing/maintaining, it's fixing. Now it was mentioned above that your usage would amount to £2700 per year more in fuel for the petrol boat. A turbo can be had for about £800*. To recon a 290dp drive maybe £1500*. My point is that the savings in fuel should pay for any extra maintenance quite easily, and you still benefit from easy to obtain fuel and a higher demand, higher price, easier sale when the time comes.

Having said that, you appear to have your mind made up, so you should go with what your head is telling you and not listen to us old boogers.

ps. one last point. a paid of mistreated 10 year old drives will be a worse proposition IMHO that a pair of 30 year old well maintained drives. How you find out the reality of their whole life treatment is the difficult thing. Good luck with whichever way you go!

*http://www.ebay.co.uk/itm/New-Origi...647984?hash=item237be7dbb0:g:lPAAAOSwEzxYV~ui

*http://www.ebay.co.uk/itm/Volvo-Pen...276312?hash=item4b0af37bd8:g:yV0AAOSwk1JWb9U5 ( I assume there may be some parts on top of this)
 
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I think the thread has drifted somewhat to the classic 'Petrol vs Diesel' discussion, which tends to assume that you are comparing identically aged/condition boats with one another - which is only ever possible for new boats.

What the OP was really asking was - 'Which is better - nearly new petrols or 30 year old diesels?'

If you have nearly new petrols the reliability (fun) and the ability to use the boat should be ok. With engines that are 30 years old, what is the probability of serious stuff going wrong and spoiling your weekend / holiday?

New D4s are about £35,000 each, plus fitting..... So, potentially a £70k bill if it all unfolds.

Yes indeed - wouldn't consider 30 y/o petrols/drives at any more than about £8-10K as a repower project! The boats are indeed identical - give or take normal condition variations (The petrol has been refitted, but so have some of the diesels that crop up) Would be s/h D4's etc, but would be able to bide time and pick up for cash and store until such time as I had a suitably matched pair. Employer is a VP Centre however so ear to the ground if required! Would fit myself, so based on what I've seen over last couple of years, total cost perhaps £30-35K

rbcoomber - I'm pretty sure I know the boat you are referring too. Don't worry, I'm not in the market for that boat but I'm rationalising a similar equation...

Some of my posts refer to Princess 266 with 205 v6s and not the above boat.

In the RIB world I've always enjoyed the 'new (ish) engine, on an old boat' as the engine is the key element to happy, safe, fun, hassle free boating.

Yes, I suspect you do ;) but the age thing is key really as I hadn't considered petrol until this appeared on my radar a while back!

If fuel cost is not an issue and performance/top speed is the priority you should go with the petrols.

It IS an issue, but not the only one - speed is nice, but ultimately a pair of D4-300's would do the same... And as the Arrowbolt project proves, I'm certainly not impatient and enjoy the journey as much as the destination! (Starting to sound like a metaphorical rag 'n' stick guy now! :p )
 
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