Inboard or outboard engine

[AngusMcDoon]

In 20 years of ownership I sailed nearly 50k miles on my 10hp outboard powered Dragonfly, from the Scillies to the Shetlands and everywhere in between. It can be done.

Here are some experiences...

- Never had any electrical problems, never had a failure to start, never had to change a sparkplug in a bouncy sea. I had one fuel pump diaphragm split. In 20 years that was all.
- External fuel tank. Refill using a siphon pump. No spillages. Not difficult.
- No diesel bug. Petrol doesn't seem to suffer from this. If there's any crud in the tank, lift it out and remove it. 5 minute job.
- Approximately 20 NM/gallon in calm conditions. Didn't see anything like some of the fuel consumptions posted here - they must be for 2 strokes.
- Extra long leg stopped the prop coming out of the water. Honda, Tohatsu and Selva makes these.
- Fine stopping in astern. Fine steering in astern. Linked tillers meant I could do a 180 degree turn in 2 boat lengths, forwards or backwards.
- Longest non-stop trip under engine was Pwllheli to Troon, but fuel got low near Girvan so went in to refuel. Over 200 miles.
- The first engine wore out after 30k miles. Replacement was £2k. Fitting took 5 minutes. A gorilla sized mechanic from the shop lifted it on for me.
- When you decide you need a new one, delivery is a few days. It can be months for an inboard diesel. (Things may have changed with current supply chain problems).
- Maintenance is easy and minimal. To anyone who tinkered with Japanese motorcycles in their youth they are similar. I can cope with carbs. I wouldn't know where to start with a high pressure fuel system.
- I never locked it. The mount was through bolted to the hull. Enough to stop any casual thief if not a determined one.
- I didn't hurt my back lifting it off because I never did. Bolted on, and it stayed there.
- The charging output and a 60 W solar panel allowed me to run a small fridge, autopilot, instruments etc all summer.
- I got to know where petrol was available. On the Scottish west coast the islands are better than the mainland usually.
- I could lift the prop and leg completely out of the water. Anode unnecessary and fouling non existent. No prop drag. Replacement prop cheap if needed.
- Electric start which was always instant, but hand starting was easily done as well. This negated the need for a separate starting battery.
- All fuel and oily smells are kept outside. The cabin and bilges never smelled like a stinky old engine. This is an advantage you don't often hear mentioned.
- I picked up ropey fishing detritus on the prop occasionally. It's a 5 minute inconvenience with an outboard.
- While the impellor can't be replaced at sea they rarely seem to fail on outboards. I replaced them every 5 years but there was never any damage or wear.
- It's important to keep weight down on small boats, especially multis, and not having a 200kg lump of cast iron lurking down below means I can carry extra supplies of Pringles.

It's not all inboard diesel good, petrol outboard bad. There are advantages and disadvantages to either.

 

[25931]

One choice I have is either a small yacht with an inboard or another with an outboard.Having had various yachts with inboards there seem to be quite a lot of downsides which with age don’t get better.Amongst the problems are getting at filters and seals fuel tank drains and shaft connections in general getting at stuff in awkward places and the need for an engineer to come to the boat if required,whilst an outboard is all there to sea and can be taken to a shop if required.The downside ofthe outboard is it’s not so handy to start and use in maneuvering situations nor in a rough sea.Not being in anyway an engine fixer much to my shame I am leaning more towards an outboard on a 7 meter yacht

Neither of us is exactly a novice and we both know that there's no such thing as perfection (especially in boating).There's lots of experience in the answers but only you know what you really want so select those that suit you and be happy.

 

[Mandarin331]

Just been searching for a 7m yacht and after having inboard diesels for the last three boats a cockpit well mounted outboard was a must have. Just fed up with heavy, smelly diesels costing an arm and a leg to repair, the final straw was a repair costing the equivalent of two new outboards.

I would not have a transom mount, nor another Seagull, but happy to have a modern 4 stroke ob, however this is only for river and inshore cruising / short hops which is what we plan for the future.

 

[Wansworth]

Buying a secondhand boat my biggest worry born out of previous experience has been the inboard engine and all the stuff pertaining to it,so many unknows and rectification needing a marine engineer or electricianBeing over70 getting into small spaces to check or fix something I think has convinced me that unless it’s a newish installation with good access I will plum for an outboard installation

 

[Stemar]

That's a reasonable decision in your circumstances.

I do like Jamie's idea of a backup, but that could be your dinghy outboard on a lifting bracket. That arrangement got me out of a hole a couple of times, once when my old engine died, and again when I'd turned the fuel off to do something and forgot to turn it back on here was enough fuel to get me out of Yarmouth, and start sailing, but not enough to get into Portsmouth

 

[Frogmogman]

Angus McDoon makes some excellent points in favour of outboards in certain applications. A boat like a dragonfly will sail at decent speeds in very light airs, so is not as reliant on motoring everywhere. However, to do so weight needs to be kept to a minimum. The light weight of an outboard (and zero drag from a prop that is only in the water when motoring) help the sailing performance.

Way back when the J29 first came out in the UK, I used occasionally to race on one. We kept the outboard on the floor in the middle of the saloon most of the time, only getting it out when there wasn’t a breath of wind. We used to manoeuvre the boat into and out of the Lymington Yacht Haven under sail. One of the other early J29s was fitted with an inboard diesel; it was nothing like as fast.

As has already been pointed out, it really depends on what sailing programme the OP envisages. AIUI, the plan is for some coastal pottering around the rias. For a 7m boat, an outboard would be perfectly adequate for this.

 

[Greenheart]

A large majority of Achilles 24s (7.2 metres) use outboards, but some squeezed a petrol inboard below the cockpit...that would seem the worst of all possible worlds. I also saw one with an ancient, very small BMW diesel inboard, of unreliable reputation.

In a yacht that size, one benefit of an outboard is simply not having to share the tiny cabin, with it. Mine was an amply powerful two-stroke 5hp weighing 20kg. The engine sat in a well. Some owners devised clever ways to fair-over the cavity around the engine leg, leaving the hull smooth and the engine ready to go. I kept a smaller, spare outboard in a locker, so I had no fear of failure en route.

That is not to pretend I enjoyed lifting the 5hp out to secure it below the cockpit when we left the boat, and nor was it peaceful in use; although I've sat above some horribly noisy diesels, too.

But Wansworth has identified the biggest issue...if an old boat has an old diesel, who knows if it has been looked after? The smaller the boat, the more prohibitive is the cost of a new (or even an old) replacement diesel, relative to replacing an outboard.

A fellow at my club explained having put a new diesel in his 1980s Beneteau First 27, as sensible in the long term, but it pained him to admit that my estimate of £5,000 as the engine's price, was only half what it had finally cost, fitted.

I'm keeping an eye out for a 40-year-old design built in two sizes: one is small, but was always sold with a diesel; the other is really small, and could only take an outboard. In principle they're both affordable, but if the outboard fails on the smaller boat, it wouldn't be much financial sweat (or delay) to re-engine and get going again. But, if the diesel needed replacing...?

At this level (and at the budget that is usual for this size of yacht), an outboard is a smart choice.

 

[LONG_KEELER]

A large majority of Achilles 24s (7.2 metres) use outboards, but some squeezed a petrol inboard below the cockpit...that would seem the worst of all possible worlds. I also saw one with an ancient, very small BMW diesel inboard, of unreliable reputation.

In a yacht that size, one benefit of an outboard is simply not having to share the tiny cabin, with it. Mine was an amply powerful two-stroke 5hp weighing 20kg. The engine sat in a well. Some owners devised clever ways to fair-over the cavity around the engine leg, leaving the hull smooth and the engine ready to go. I kept a smaller, spare outboard in a locker, so I had no fear of failure en route.

That is not to pretend I enjoyed lifting the 5hp out to secure it below the cockpit when we left the boat, and nor was it peaceful in use; although I've sat above some horribly noisy diesels, too.

But Wansworth has identified the biggest issue...if an old boat has an old diesel, who knows if it has been looked after? The smaller the boat, the more prohibitive is the cost of a new (or even an old) replacement diesel, relative to replacing an outboard.

A fellow at my club explained having put a new diesel in his 1980s Beneteau First 27, as sensible in the long term, but it pained him to admit that my estimate of £5,000 as the engine's price, was only half what it had finally cost, fitted.

I'm keeping an eye out for a 40-year-old design built in two sizes: one is small, but was always sold with a diesel; the other is really small, and could only take an outboard. In principle they're both affordable, but if the outboard fails on the smaller boat, it wouldn't be much financial sweat (or delay) to re-engine and get going again. But, if the diesel needed replacing...?

At this level (and at the budget that is usual for this size of yacht), petrol's a smart choice.

Yes. Boats with old diesels and old teak decks often bring out the worry beads for sailors on a low budget. Having to renew either often leads to end of boat or a big investment over many years. The outboard option can work well for boats up to about 27 ft.

January 2007 was an interesting year for outboards. You could only buy 4 strokes in the UK. The market responded somewhat earlier and it made life much easier for cruising sailors to extend their range and make life a bit quieter for them and perhaps more reliably. I know there is some concern about having petrol onboard, but fires are rare and gas explosions seem to major on inland hire caravan/boats.

 

[mrming]

A large majority of Achilles 24s (7.2 metres) use outboards, but some squeezed a petrol inboard below the cockpit...that would seem the worst of all possible worlds. I also saw one with an ancient, very small BMW diesel inboard, of unreliable reputation.

In a yacht that size, one benefit of an outboard is simply not having to share the tiny cabin, with it. Mine was an amply powerful two-stroke 5hp weighing 20kg. The engine sat in a well. Some owners devised clever ways to fair-over the cavity around the engine leg, leaving the hull smooth and the engine ready to go. I kept a smaller, spare outboard in a locker, so I had no fear of failure en route.

That is not to pretend I enjoyed lifting the 5hp out to secure it below the cockpit when we left the boat, and nor was it peaceful in use; although I've sat above some horribly noisy diesels, too.

But Wansworth has identified the biggest issue...if an old boat has an old diesel, who knows if it has been looked after? The smaller the boat, the more prohibitive is the cost of a new (or even an old) replacement diesel, relative to replacing an outboard.

A fellow at my club explained having put a new diesel in his 1980s Beneteau First 27, as sensible in the long term, but it pained him to admit that my estimate of £5,000 as the engine's price, was only half what it had finally cost, fitted.

I'm keeping an eye out for a 40-year-old design built in two sizes: one is small, but was always sold with a diesel; the other is really small, and could only take an outboard. In principle they're both affordable, but if the outboard fails on the smaller boat, it wouldn't be much financial sweat (or delay) to re-engine and get going again. But, if the diesel needed replacing...?

At this level (and at the budget that is usual for this size of yacht), petrol's a smart choice.

What boat are you looking out for Dan?

 

[Greenheart]

I would very much like to tell you, Cap'n, but I'm embarrassed, and might simply be dissuaded by actually stepping aboard one.

It's not much of a boat nor a popular design, and my plans for it are typically eccentric, so I've decided to stay quiet until I've got her.

Then I'll float away under cover of night before the howls of humorous disbelief and contempt begin.

But thanks for asking!

 

[AngusMcDoon]

I would very much like to tell you, Cap'n, but I'm embarrassed, and might simply be dissuaded by actually stepping aboard one.

It's not much of a boat nor a popular design, and my plans for it are typically eccentric, so I've decided to stay quiet until I've got her.

Then I'll float away under cover of night before the howls of humorous disbelief and contempt begin.

But thanks for asking!

Got to be a MacGregor 26

 

[mrming]

Got to be a MacGregor 26

I secretly hope it’s a Buckler 24. My more realistic guess, though, is going to be some flavour of Hardy motor sailer.

 

[Greenheart]

I had been on the point of stating pre-emptively that it is not a Buckler 24, but for some reason I imagined that design wouldn't occur to anyone.

On that basis though, I must add that it isn't a MacGregor, either. I looked dispassionately at the Mac26 design, and its long run of huge commercial success, which ought not to be disregarded lightly...

...but I reckon a large part of the appeal of our boats, isn't logical, so while my actual use of any yacht may only be fairweather-coastal, and while it would be great to cover 18 miles in an hour, the Mac's light plastic interior is too awful - too high a price to pay. Plus they're not exactly cheap...in fact they're not as cheap as they look.

 

[wombat88]

The Buckler, a fine craft in my eyes, has the inboard under the centre cockpit floor so that you can attend to its needs while the family sleep in fore and aft cabins.

The Hardy motor sailer is as wide as it is long but another fine craft. The hull is excellent for a motor boat but from what I've seen the m/s tends to go sideways a fair bit with significant 'top hamper' and still needs quite a few hp.

Having said that both are charming in their own way.

 

[oldmanofthehills]

I had a Jaguar 21 with outboard in a well. 8HP 'sail drive' Tohatsu pushed her along quite well. Using both rudder and outboard manoeuvrability could be quite impressive once you have worked out the knack.

But...
1 I was advised not leave the outboard immersed for weeks. So that involved lifting the engine and resting it on something
2 Security. Padlocks and chains etc. 'Oh put it in the cabin' they say...well, as you get older 8hp gets heavier and heavier.
3 Reversing. Outboards make pretty hopeless brakes. An inboard seems much more capable of stopping a boat.

I wouldn't go there again

Similar problems on our Anderson 22. And the extra weight of a decent sized (8HP) outboard that far astern was a real problem - may even have contributed to her sinking on the moorings in an admittedly violent storm.

 

[Stemar]

gas explosions seem to major on inland hire caravan/boats.

I would guess that a big percentage of those would be hire boats with people who are unfamiliar with the system.