Selva 2.5hp Seahorse

dartmoor

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Has anyone got one?

I bought one on the strength of the Yachting World report on 2.5hp outboards.

At first my impression was it was well built.....BUT

1. Its the noisiest engine ever! Makes a Honda 2.3 sound quiet (I even think a seagull might be quieter). I know air cooled engines are noisy, but this one takes the prize! Its only bearable at tick over - after that it sounds like a Honda amplified!

2. I can foresee loads of design issues. Its just too clever - and rather like an Alfa Romeo, seems build to run well....briefly! Firstly, the fuel system. There is no gravity feed, no fuel vent on the fuel cap, no fuel tap. Upside is no smells or leaks possible. It relies on a diaphram, and a fuel bulb, that you can only get at by removing the cowling! Downside - you cannot run the carb dry. With our EC formula for petrol we all know that a) it goes off after a month, b)goes gummy and blocks jets if left in the carb, and c) eats anything not made of high quality metal. So no doubt it will eat the diaphram, the priming bulb, and the little rubber pipe that mixes fuel with two stroke oil. I have just had to rebuild a chain saw carb for all these very reasons, and it was a Husquvana, not a cheap Chinese one!

3. The centrifugal clutch only kicks in at moderately high revs, and then the gears run at speed. It seems that the engine is not designed to allow slow forward running - its just on or off. Much much worse in this respect than the Honda. So coming alongside will be...er...interesting.

4. The idea of having a four stroke cycle, but mixing petrol and two stroke oil worries me. It does sound a clattery engine - both clutch rattle at the point just prior to engagement, and valve clatter. Tiny pipe taking the oil to the carb. So apart from maybe the design not enough oil getting around the engine for any durability, if the oil pump fails, the pipe fall apart or blocks, its curtains!

5. The recoil works by a heavy spring which stores the energy from two or three pulls and then releases, so that the engine supposedly starts itself. Just what is the point of that on a 2.5hp?? It just puts the cord under extreme tension as you pull it - so can't see that lasting forever!

I decided this was a bad buy. Now it seems an even worse buy as I can't get any interest in it when trying to sell it. Even dealers won't look at it, even on brokerage, as their response is "unknown make in UK, nobody buys them, parts very difficult to get..."

So I may have to live with this complex noisy little Italian designed disaster waiting to happen.

Just trying to seek solace from anyone who might have one, and can tell me that they love it! Even more impressive if it is several years old, and still works!
Mine is unloved in my garage at the minute with me wishing I had bought a Honda....
 
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Yes, very encouraging! I should have researched first - Selva 2.5hp was not a good option - pity Yachting World testers raved about it. They don't have to live with it!
 
Good thread. I have googled the Selva 2.5hp, and can't find anyone whose had one and written about it. Well, the silver lining - unlikely to be stolen as its soooo rare, and no would buy it anyway. I was on the Med in the summer, and didn't see one there either? Perhaps they have only made two - the one that Yachting World tested, and the one I bought...

The manual is a good read - its either been translated from Italian by Google, or by a 12 year old Italian who has only just grasped the basics of English.

The most useful diagram and paragraph is the one telling you that you shouldn't reach down in the water and grab the propellor whilst the engine is running!
 
Has it actually gone wrong or is this a pre-emptive/speculative moan?

Has anyone got one?

I bought one on the strength of the Yachting World report on 2.5hp outboards.

At first my impression was it was well built.....BUT

1. Its the noisiest engine ever! Makes a Honda 2.3 sound quiet (I even think a seagull might be quieter). I know air cooled engines are noisy, but this one takes the prize! Its only bearable at tick over - after that it sounds like a Honda amplified!

2. I can foresee loads of design issues. Its just too clever - and rather like an Alfa Romeo, seems build to run well....briefly! Firstly, the fuel system. There is no gravity feed, no fuel vent on the fuel cap, no fuel tap. Upside is no smells or leaks possible. It relies on a diaphram, and a fuel bulb, that you can only get at by removing the cowling! Downside - you cannot run the carb dry. With our EC formula for petrol we all know that a) it goes off after a month, b)goes gummy and blocks jets if left in the carb, and c) eats anything not made of high quality metal. So no doubt it will eat the diaphram, the priming bulb, and the little rubber pipe that mixes fuel with two stroke oil. I have just had to rebuild a chain saw carb for all these very reasons, and it was a Husquvana, not a cheap Chinese one!

3. The centrifugal clutch only kicks in at moderately high revs, and then the gears run at speed. It seems that the engine is not designed to allow slow forward running - its just on or off. Much much worse in this respect than the Honda. So coming alongside will be...er...interesting.

4. The idea of having a four stroke cycle, but mixing petrol and two stroke oil worries me. It does sound a clattery engine - both clutch rattle at the point just prior to engagement, and valve clatter. Tiny pipe taking the oil to the carb. So apart from maybe the design not enough oil getting around the engine for any durability, if the oil pump fails, the pipe fall apart or blocks, its curtains!

5. The recoil works by a heavy spring which stores the energy from two or three pulls and then releases, so that the engine supposedly starts itself. Just what is the point of that on a 2.5hp?? It just puts the cord under extreme tension as you pull it - so can't see that lasting forever!

I decided this was a bad buy. Now it seems an even worse buy as I can't get any interest in it when trying to sell it. Even dealers won't look at it, even on brokerage, as their response is "unknown make in UK, nobody buys them, parts very difficult to get..."

So I may have to live with this complex noisy little Italian designed disaster waiting to happen.

Just trying to seek solace from anyone who might have one, and can tell me that they love it! Even more impressive if it is several years old, and still works!
Mine is unloved in my garage at the minute with me wishing I had bought a Honda....
 
Just to finish off the sorry tale of the Selva 2.5hp...to warn anyone unsuspecting.

I was really concerned about the rattly nature of the engine from brand new, and so I tried and tried to get a response from Selva UK. After many emails, I finally got a response to say that the business in the Uk was being sold - so basically they weren't interested - the gist of it was "go away, its nothing to do with us" - although a little politer than that.

I then took the engine out on my dinghy. It ran for 15 minutes and then totally died, and would not restart. I got it home and it started but would not engage the clutch at all, and would not rev - and would die again and not restart. Something sounded very wrong.

To their credit, the UK dealer (not Selva) who placed the original order with Selva for me said they take the engine back and argue the case with Selva Marine (if they could ever get a response!). They gave me an exchange for a Mercury 2.5hp - which I am very pleased with - a properly built engine.

I think the Selva was appallingly made, and it seemed that basically the clutch mechanism had just disintegrated through a serious design or manufacture fault. The after sales service by Selva is non-existent in my experience. I even tried to correspond with Selva Italy - they couldn't be bothered to reply even.

I would seriously warn anyone unsuspecting about the risks of buying a Selva - you are on your own if there's trouble. The warranty is therefore pretty useless. I was lucky in that the place I bought this engine through took it back, even though really I had just used them to place an order directly for Selva for the engine to be delivered to me.

I may have just been unlucky of course - but the serious issue for UK buyers, is that I am not sure that Selva is properly represented in the Uk any more, and you are probably going to get as much after sales service and spares support as you would if you bought an unknown make from China.
 
Hello all.

Just found out these postings for the Selva horse 2.5 dingy engine.
Well your cases suit mine. I bought this engine and I run into trouble cause mainly people dont really appreciate the use of the Starting Cord (u know the one that stores energy)...So I ended up with a faulty engine with only 3hours of working time. I want to say to you that I dismantled the engine myself, I even built a custom tool to hold the Flywheel from rotating while screwing the nut that holds it on the main crankshaft. An yes I have the spare parts manual as well.

The main issue with these engines are two things.

1. The auto starting mechanism, which correctly described as a part that stores the energy and then autostarts the engine.
2. A failed component, due to incorrect tourque setting by the factory (as it is already specified as wrong setting)

This failed component is a pin that securely holds the Flywheel on the main crankshaft. The Flywheel must and it is also secured by a 10mm Nut. But the Nut is not appropriately torqued. It is torqued to 5Newton Meters (basically the human force to screw a nut) whilst it has to be at least 35Newton Meter from engineering perspective. And this wrong adjustment is set by the Factory and indicated into the spare parts manual pdf which I made a search via google and found it. The Manual says to torque this nut to 5NM. Wrong !!

Incident
----------
The AutoStarter broke because my charterers did not appreciate its use as correctly reported by one of the users of this thread. Whats the use ? Why do you need an auto starter on such small engine ?
Well these charterers broke initially the 'Starter'. And because these engines are very strong (because they are 2 stroke engines and not 4 stroke) due to their Timing Advance, they tend to try and rotate the engine crank in the opposite direction as I found out in 3 instances.

1. When engine runs out of petrol, and shuts down
2. When you try to start the engine using the AutoWinder, and you mistakenly think that this is the normal Dingy Start Cord.
3. When you choke the engine as a result of the point 2.

In the above 3 instances the engine will try to rotate ccw and exactly because of this ccw rotation, the pin brakes rendering the engine timing with all other mechanical consequences. Of course the reason behind the CCW rotation, is the 2 Stroke engine powerfullness.

The pin is 'eaten away' by the flywheel (This pin is part no Q227631 described as Key, item 37 and F/Wheel is part no Q244037 item 38 in the drawings.), and renders the hole of the FWheel with iron debris.
Thus when you try to re-seat the flywheel on the crankshaft, it will not seat properly (as tight as possible to adhere correct friction and therefore transfer of energy). So the use of fine sandpaper with hands is required to make the hole as smooth as possible making sure that all 'Key' debri is now away from the hole.
Having done that and try numerous fits, you will discover that the F/Wheel is now seated closely (almost touches) the cylinder block but also has a very good fit on the crankshaft (tight). So you incorporate the use of the lathe machine and you 'eat' about 0.5cm of the flywheel blades and make it shorter. Then you insert a new key on assebly the engine back, and screw the M8 nut to 25 - 35 NewtonMeters. Assebly the engine back and it will start with 1st kick.

Now I agree that some people are more appreciating than others. However this is not a matter of how much appreciating one can be. Because am an Engineer (Accredited by IET) I used my knowledge, expertice and hands on experience and fixed this engine. I know what actions to take and run ashore in case this engine stops working while at sea, with or without tide. You cant expect everyone to be as much as appreciating as me (for example). I think that Selva should withdraw all of their Seahorse engines or make necessary re-adjustments so that people make their money worth, and also avoid any safety issues.

Despite all efforts to fix these issues, I have chartered my boat with the Dingy and its Selva Engine. The charterers reported that the engine worked and then suddenly stopped and never worked again.
So stay tuned for next ...things to come.
 
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