Diesel Outboard 5hp 25kg

[fuss]

I think we are at the stage where it is possible to make a lightweight diesel outboard that runs quietly, without smoke.
We have the common rail and piezo injector systems for efficiency and the modern diesel can be boosted to produce similar hp to petrol engines.
These technologies have made it possible for us to have diesel cars that run just like petrol.
I could imagine that a state of the art diesel engine boosted with a small supercharger could easily produce 5 hp. The size might only be 50cc. The outboard needs a total weight of around 25kg.

A conventional diesel needs roughly 400cc for 10 hp and so in any sort of outboard form, is going to weigh roughly 60 kilos or more, produce smoke, noise and vibrate.
Yanmar used to make 18hp and 30hp outboards but they ran just like what is written above and weighed lots. They stopped making them as they could not satisfy emission requirements.

I know many people will say that it will be too expensive etc etc, but lets forget that point for the moment.

So is it possible to engineer a 25kg 5 hp diesel outboard that runs reasonably quietly and satisfies the eu emission regulations using the latest diesel technology?

I cant see any reasons why this could not be done now.

Do we have any engineers or anyone with experience in this area who could comment on what Ive written ?

 

[Jim@sea]

If Mr Dyson was into boating we might stand a chance and your 25kilo requirement is too low as the engine mass would be larger but preferably a 9.9 hp, twin cylinder, water cooled. (for quietness) Thats where the greatest sales would come from. This would make outboards cheap to run as you would probably use 2 liters diesel per hour

 

[ytd]

many aust navy boats use diesel o/b on their ribs because of the 2 fuels rule which says you can't have more than 2 fuels on board. So if you have a diesel main engine and a helo using avtur then you can't have a petrol o/b. They work - but are not well liked by the boat crews. No idea who makes them.

 

[Seajet]

Diesel outboards were made a few decades ago, but didn't catch on due to weight; I agree a modern intelligent design might be a go-er, but weight is everything, and there would also be a learning curve with a supercharged engine, throttling down as one approaches a boat or slipway might be a 'dull spot' with almost no power...

Interesting to read that about the Australian Navy, I admire the 'green' spirit, but can't help thinking that's working with an arm behind ones' back, for the military - and the way things are going, in the mid - long term things might be too serious to allow such protocols.

There is the point that one can well do without petrol around if taking a hit, see such books on the Falklands War as 'Ordeal By Exocet' - but then a warship has a lot of combustible items, such as pressurised injected fuel and ammunition.

Please don't mention Dyson, a genius at marketing not design.

My local electrical dealer always seems to have a row of Dyson vacuum cleaners waiting for repair; and a consumer report recently judged the things as " a triumph of clever marketing over quality " !

And he laid off UK workers so as to use cheap Asian labourers.

I am not in the 'hoover' business BTW.

 

[reeac]

Dysons and diesels.

It's straying from the thread but we're on our second Dyson, the first one having had 10 or more years of use with no problems until the mains lead became detached. I mended it and still have it but SWMBO thought that it was time for a new one so it's been relegated to my workshop. Back to very small diesels: non-turbo you might assume 30 bhp/litre and so 100 cc. swept volume for 3bhp but is there a problem with required tolerances when you get down to 100cc. swept volume? What do model aeroplane people have to say?

 

[electrosys]

Please don't mention Dyson, a genius at marketing not design.

Cyclone vacuum technology was developed donkey's years ago by Xerox and Kodak for use in their high volume photo-copier machines (to remove any excess fine toner powder which would otherwise become airborne and be inhaled).
Dyson appears to have lifted the idea and gives the impression that the invention is his.
Clever of him to see the domestic vacuum-cleaner application though ...

 

[Lakesailor]

The weight issue would be tricky to address. Diesels need flywheel mass to smooth out the power stroke "bang" (very technical) and a supercharger would add weight and complexity (and heat).
The owner would need to develop a massive right arm to pull-start it unless it was electric start (more weight) or used decompression. That may be a bridge to far with a small capacity diesel, and again would be relying on flywheel mass to overcome the compression when the valve shut.
It could all be done, I have no doubt, but would it be commercial suicide on such a small motor?

 

[westernman]

I can't help thinking that there is a much bigger more profitable market for a very light, small out board which runs on petrol and produces around 3HP.

If you can make it 2/3 the weight or less than the current ones (such as Honda, Suzuki etc), I think you might be on to a winner.

Diesel would be cool, but in the small outboard market, weight is more important than anything else (IMHO).

 

[reeac]

Cyclones

Cyclone vacuum technology was developed donkey's years ago by Xerox and Kodak for use in their high volume photo-copier machines (to remove any excess fine toner powder which would otherwise become airborne and be inhaled).
Dyson appears to have lifted the idea and gives the impression that the invention is his.
Clever of him to see the domestic vacuum-cleaner application though ...

Cyclones for powder separation go back way further than Xerox - probably to the early 1900s as a guess. I first heard of them in the early 1960s I'm sure that one could find out via Google..

 

[Tranona]

The main advantages of diesels (robustness, long life, greater efficiency and fire risk) disappear in the small outboard market. Weight and simplicity are key which is why the 2 stroke ruled until legislators unfairly attacked them. Typically such engines are used for a few minutes at a time and even over a lifetime total hours in the low hundreds rather than thousands.

Currently only real functional problem is excess weight and a diesel is not going to cure that - unless you go for a 2 stroke diesel.

It is potentially different if you move up to the small commercial market, but even there, nobody has made a successful diesel competitor to a conventional petrol outboard.

 

[PetiteFleur]

I can't help thinking that there is a much bigger more profitable market for a very light, small out board which runs on petrol and produces around 3HP.

If you can make it 2/3 the weight or less than the current ones (such as Honda, Suzuki etc), I think you might be on to a winner.

(IMHO).

I quite agree, just bought a Suzuki 2.2 as an alternative to my Honda - it weighs about 3 kg less. Even better a 2HP outboard about 8kg would be a winner.
I bought from an auction, a few days ago, a 1938 Evinrude Elto 1.1HP outboard which weighs 8½ lbs(4kg) so it should be possible for 2HP/8kg nowadays. All it needs would be one of the big manufacturers to have a go.

 

[Lakesailor]

A quiet, aircooled motor would be the thing.
Bit difficult of course.

 

[old_salt]

I quite agree, just bought a Suzuki 2.2 as an alternative to my Honda - it weighs about 3 kg less. Even better a 2HP outboard about 8kg would be a winner.
I bought from an auction, a few days ago, a 1938 Evinrude Elto 1.1HP outboard which weighs 8½ lbs(4kg) so it should be possible for 2HP/8kg nowadays. All it needs would be one of the big manufacturers to have a go.

Gas. or LPG would be an alternative. Engine size / weight would be a none problem.
It runs Stacker Trucks and Cars very well.
We have LPG as a normal on most boats it comes in very nice handy containers.
The refiling could be sorted so as you could fill up a purpose made tank at any petrol station supplying LPG. (it would satisfy the two fuel rule )
Good on the emission side too.

As for Mr Dyson inventing a OB no thanks it would bung up in all it's little orifices every few hrs use just like his vacs do.
I must have unbunged dozens in my working life.

The Cyclone vacuum technology is only a variation on a centrifuge and engineers have been separating oils with them for years.
spent many a watch at sea cleaning up heavy fuel and lube oil.
There is no corner shop or garage to get more from in the middle of the Atlantic.

 

[jimmcgee]

watched a program on the open university one drunken night in the 80,s when it was the only thing on late tv.

The program was about some guy who was making Cyclone cleaners for woodworking firms to clean the air in the workshops , and seen the potential for a new sort of vacuem cleaner

poor guy was all over the place looking for investors but could not get anyone to back him

wonder how he got on lol.

 

[saltwater_gypsy]

Here is glimpse of the future with the Dyson Diesel Outboard.
OOps, typo I meant Yanmar!!!

http://www.youtube.com/watch?v=1Pu4RJmevrQ&NR=1

 

[fuss]

The weight issue would be tricky to address. Diesels need flywheel mass to smooth out the power stroke "bang" (very technical) and a supercharger would add weight and complexity (and heat).
The owner would need to develop a massive right arm to pull-start it unless it was electric start (more weight) or used decompression. That may be a bridge to far with a small capacity diesel, and again would be relying on flywheel mass to overcome the compression when the valve shut.
It could all be done, I have no doubt, but would it be commercial suicide on such a small motor?

Lakesailor, good point with the starting that would need some decompression methodology.

Complexity... its 2010, we should be able to solve these old diesel problems by now. It need to be supercharged to get the hp of a modern diesel.

could I politely ask that we stop with the dyson stuff as it removes the focus

surely in 2010 we can do for the outboard industry what the diesel has done for the car industry.

 

[Lakesailor]

Goods Direct are offering a 4hp diesel at 45Kg


and also this classy number at a higher output

 

[Tranona]

Lakesailor, good point with the starting that would need some decompression methodology.

Complexity... its 2010, we should be able to solve these old diesel problems by now. It need to be supercharged to get the hp of a modern diesel.

could I politely ask that we stop with the dyson stuff as it removes the focus

surely in 2010 we can do for the outboard industry what the diesel has done for the car industry.

Not sure why you think there is a need for a diesel outboard in the small HP category. Seems to me you are looking for a solution to a problem that does not exist. The problem with the current 4 strokes is weight and complexity but you are suggesting a solution that is even more complex and arguably even heavier.

Not sure either that diesels are the way to go in the future car industry. True they have made a significant impact over the last 20 years, but this was helped by substantial subsidies through lower fuel taxes in many of the main markets. Now that has gone and small capacity petrol engines are achieving high outputs and low fuel consumption, diesels in cheaper cars are on the way out. Just look at the 1.6 petrol engine in the new Focus. 148hp, consumption in the mid 40s. Compare that with my last generation state of the art 2 litre diesel with 130hp and low 40s consumption of a fuel that costs 6 or 7% more.

The "solution" to small hp outboards is a 2 stroke that meets emmissions requirements. Technically feasible, but the market is so small, I can't see any manufacturer putting in the R&D when there is little spin off for other applications.

 

[fuss]

Goods Direct are offering a 4hp diesel at 45Kg

Thanks, thats very interesting 4 hp at 45kg.
So it seems that it is possible for the Chinese to make a 45kg, 4hp diesel outboard without using the latest diesel technology.

45kg is too much weight. we need 25kg, clean burning and more hp from less cubic capacity.

 

[fuss]

Not sure why you think there is a need for a diesel outboard in the small HP category. Seems to me you are looking for a solution to a problem that does not exist. The problem with the current 4 strokes is weight and complexity but you are suggesting a solution that is even more complex and arguably even heavier.

Not sure either that diesels are the way to go in the future car industry. True they have made a significant impact over the last 20 years, but this was helped by substantial subsidies through lower fuel taxes in many of the main markets. Now that has gone and small capacity petrol engines are achieving high outputs and low fuel consumption, diesels in cheaper cars are on the way out. Just look at the 1.6 petrol engine in the new Focus. 148hp, consumption in the mid 40s. Compare that with my last generation state of the art 2 litre diesel with 130hp and low 40s consumption of a fuel that costs 6 or 7% more.

The "solution" to small hp outboards is a 2 stroke that meets emmissions requirements. Technically feasible, but the market is so small, I can't see any manufacturer putting in the R&D when there is little spin off for other applications.

My understanding is that the industry is working on an emission friendly 2 stroke and the market might not be so small.
I did not at this stage want to discuss who would buy this 25kg clean burning diesel outboard. I wanted to discuss if it is possible to make from an engineering perspective.