6hp... 3.5 tonnes... the film

dylanwinter

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I was amazed at how well it worked

I do need to strengthen the transom where the outboard bracket is attached

there is just a single metal backing plate on the inside so I need a larger chunck of ply and some sickaflex because the transome was flexing around a fair bit

I have to say that the outboard at 5 knots was quieter than the inboard at 5 knots - especially when on the foredeck or in the cabin

in the cockpit it was neither here nor there

I will do some efficiancy tests while doing the trip to Scotland at the end of May

To those who felt that a 10hp outboard on a Centaur would not be man enough for the job..........

Pah!



S1620089-2-215x300.jpg
 
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dylanwinter

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Deep down inside you still really want to cut a hole in a Centaur, don't you? Nice video, thanks for posting.

I think it would have been an experiment worth doing

and you know if I fall in love the Centaur then I could well end up selling Harmony and buying a cheaper replacement with a duff engine. I have to say that a recent run down the solent with a force five to six up her chuff was a pleasant experience

half a genoa and the tiller pilot in control for most of the time

in the one tonne Katie L it would have been a bit more of a challenge

D
 

simonfraser

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Yeh, no big surprise, flat water.
I certainly classify myself as a comfort / leisure sailor and would not choose to be out motoring into a chop.
But if I had to, my tiny o/b would not be able to cope, 2.5hp on 7m trimaran.
I can sail into a chop no problem, it's only for picking up the mooring.
Has not been an issue, yet !
 

CAPTAIN FANTASTIC

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I have an identical (Tohatsu 6hp) outboard witch I use it sometime for the inflatable dinghy and also keep in inside the boat for just in case that the old volvo diesel packs up at the wrong time. The long shaft four stroke 6hp Tohatsu moves my heavy boat as well as my 25 hp inboard engine. I bought new some 9 years ago for just less than £700, I think its twice that price now.
 

dylanwinter

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I have an identical (Tohatsu 6hp) outboard witch I use it sometime for the inflatable dinghy and also keep in inside the boat for just in case that the old volvo diesel packs up at the wrong time. The long shaft four stroke 6hp Tohatsu moves my heavy boat as well as my 25 hp inboard engine. I bought new some 9 years ago for just less than £700, I think its twice that price now.

I think mine was about £1200 - that was two years ago

I recently took Katie L out with a Yamaha 5hp two stroke

compared to the Tohatsu 6hp 4 stroke it was a gutless thing

I was very pleased to have it with me when the volvo controls failed

I will definatly be taking it to scotland - at least I have a plan B

Honda make a long shaft 2.3 - it would be good to see how that would do on the bracket

D
 
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Neil

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You need to compare the Tohatsu with a nice Seagull, with either a normal or barge-pusher prop...............go on, you know you want to :)
 

dylanwinter

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You need to compare the Tohatsu with a nice Seagull, with either a normal or barge-pusher prop...............go on, you know you want to :)

I think that this is an article that PBO should do

the best back up outboard

as for seagulls..... I have had hate mail from their owners ..... not nice people

they might look benign with that pipe and the breton cap.... but under the surface there is a simmering hate of clean running engines

https://www.youtube.com/watch?v=UghuKAn0Mm8

"the man is an idiot and a liar, this engine is older than the 1970's model and has been abused by a idiot (him) the boat its on his **** anyway, but that's not the point. this engine should be lowered by about 5 inches with the prop fitted. Ipersonally I wouldtake the engine off and burn that poxy boat..its more like a meths drinkers shed than a gin palace ha ha ha ."
 

JumbleDuck

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as for seagulls..... I have had hate mail from their owners ..... not nice people

they might look benign with that pipe and the breton cap.... but under the surface there is a simmering hate of clean running engines

We're not all that bad, you know. I'm not sure that a two stroke of any sort is worse than an inboard diesel, particularly if you use biodegradable two-stroke oil.
 

Tranona

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Not surprised at your speed in flat water. You need very little hp to move a boat at that speed. Your Volvo will only be producing similar hp to achieve the same. Different story going into any sort of wind and chop. Outboard will keep revving away and speed will drop but your Volvo will just draw more power and keep going.

So, a useful get you home but not a viable all weather auxiliary. Time to check over your installation so you are not let down by silly things like a loose screw.
 

Laundryman

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I have an identical (Tohatsu 6hp) outboard witch I use it sometime for the inflatable dinghy and also keep in inside the boat for just in case that the old volvo diesel packs up at the wrong time. The long shaft four stroke 6hp Tohatsu moves my heavy boat as well as my 25 hp inboard engine. I bought new some 9 years ago for just less than £700, I think its twice that price now.

+1. I have the short shaft version but with a high thrust prop. I have a fixed outboard bracket on the back of my beneteau and I used it when I suffered a blocked fuel filter. Performance was no less than the inboard although the conditions were calm and without wind. Having the back up engine keeps the wife happy!

Question for Dylan, When are you going to try your beloved Honda on the bracket? See how that performs
 

dylanwinter

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short shaft

+1. I have the short shaft version but with a high thrust prop. I have a fixed outboard bracket on the back of my beneteau and I used it when I suffered a blocked fuel filter. Performance was no less than the inboard although the conditions were calm and without wind. Having the back up engine keeps the wife happy!

Question for Dylan, When are you going to try your beloved Honda on the bracket? See how that performs

it is a short shaft and will not reach the water

I have to say that a long shaft Honda 2.3 could live on the back of the boat and be used on the inflatable

I would love to see what a long shaft would do

for the inboardophobics it would be a great comfort

D
 

ghostlymoron

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I found that my long shaft Mariner 4 wasn't much use on the dinghy. The prop hits the sand while you're still a long way out! As far as small outboards on largish yachts are concerned, they're fine in flat water as you have proved, but you won't get far in any kind of sea or chop. You need an appropriately sized well submerged prop and plenty of
low rev power to keep you going. Best advice on here is to thoroughly check out every aspect of your onboard before putting to sea.
 
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prv

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An electrical fault had us sailing into Newtown Creek at about midnight on Thursday night. Since we weren't planning to go anywhere in the dinghy the outboard was still in my shed at home (I don't leave it on the boat due to risk of theft). But if it had been, I wonder if it would have occurred to me to use it? Possibly I should check whether it can be clamped onto the rim of our transom kedge locker - having that as an option should ensure the main engine's continuing reliability :)

Fortunately I was able to repair the problem the following morning:

51BC8269-6AB9-43BD-9920-6E93CEC065EB_zpshgjcvwcd.jpg


The tide was foul through Hurst anyway, and my sailing mate Chris was using the time to prepare a truly epic mid-morning fryup, so we didn't really lose any time on our easter cruise.

Pete
 

bluerm166

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So you are really looking forward to main engine failure in the flat,windless,current free waters of Scotland ?
 

prv

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And the problem was, Pete?

Not fully diagnosed, but it went away :)

The symptom was the starter motor running continuously whenever the engine battery was turned on. Initially manifesting, while motoring normally, as the engine alarm suddenly going off and a variety of cryptic warning symbols coming up on its display (doncha just love electronic engine control systems). When I killed the engine we could hear something still running in the engine bay, this being the starter motor, so I shut off the master switch.

Of course, having been a clever-dick and fitted a single DPDT switch for both engine and domestics, this promptly knocked out all lighting and navigation kit (including depth) as well. I'd unrolled the genoa to give us a knot or two over the ground against the foul tide, and asked Chris to steer to keep us in safe water. Since it was a dark night and we were in shallowing water along an unlit stretch of shore, he quite reasonably replied "how?". I passed him my iPhone with Navionics running - may be sneered at, but it's a bloody useful backup.

Assuming that the engine electronics had got confused, I tried disconnecting the wire from the black box to the "go ahead and start" terminal on the starter solenoid. This made no difference - as soon as the power was turned on, the motor span up. So I concluded that there must be some internal short or fault in the solenoid / starter motor assembly. Since removing that requires removing the alternator for access, and I doubted that it would be a simple fix once removed, I decided that the engine was hors de combat for the forseeable. We briefly discussed the idea of temporarily applying power to start the engine, then disconnecting to stop the starter spinning, but I was reluctant to run the engine without power (no overheat or oil pressure alarms and we could have an entire knackered engine on our hands rather than just a faulty accessory), and we were also assuming that there may have been teeth stripped from the starter and/or flywheel by the constant running.

I then disconnected the engine positive lead in the battery box, so that power to everything else could be turned back on - at the time I actually sounded out loud that riff from Apollo 13 at the moment where the Command Module is coming back to life ready for re-entry :). We set the mainsail for half an hour or so to bring us up to the Newtown cardinal, then lowered it again and sailed in under just the jib, deck searchlight going to pick out the marks but also making liberal use of the new binnacle plotter.

I had naively thought that we might find a vacant mooring - assuming that on Thursday night we'd be ahead of the Easter weekend hordes. In fact, it was so busy that finding space to anchor was tricky. We picked a spot and dropped the hook in good order and under control, but unfortunately in the darkness I'd slightly misjudged the direction of the tide and once we let out a suitable amount of chain we ended up a little close to a larger yacht. In retrospect it might have been better to stay there and simply monitor the situation at the change of tide, but we decided to up sticks and try to find a different spot. As the chain was coming up, I mentioned to Chris how some people advocate wiring windlasses on the assumption that the engine will always be running while handling anchors :)

We reached back down Clamerkin Lake to the entrance, and went to tack round to go up it again for another try. Unfortunately at this point the wind died, and a lot more incoming tide than I expected was pushing us towards the mudflats by the old seawall. I called to Chris to get the anchor down, concerned that position up-wind and up-tide was something we needed to hold onto whatever happened. Unfortunately he'd mislaid the handle for the windlass clutch (for dropping under gravity) and was motoring it down relatively slowly instead. By the time it took some kind of hold (and I think even then it was dragging in the Newtown soup) we had come up against an anchored Contessa (26?). The boats never actually touched, as we fended off by hand at first and then with fenders, but it was all rather confused.

The skipper of the Contessa was understandably annoyed, but as the situation became clearer he switched into problem-solving mode and very kindly proposed to tow us up-tide a little so that we could re-anchor. In the event this didn't happen, we ended up with our anchor set under where the Contessa was lying, and we settled back some way downwind and down-tide of the rest of the fleet. According to the Yarmouth tide curves we would just float at low water; in fact the Newtown tides were sufficiently different that we were hard aground and heeling at 0630, but in mud and not really any worse than on our home berth on a very low spring.

First thing the following morning, I rowed the other chap's dinghy back over to him (it had been moved to our stern in preparation for the tow and then forgotten) and also delivered a large bottle of fancy beer (we didn't have any drinks aboard other than beer) by way of apology for disturbing him. Then I disconnected and removed the alternator, followed by the starter assembly, and got it all on the saloon table for investigation. I started by dismantling it as far as possible, and was relieved to find no stripped gear teeth (I also inspected the engine flywheel and found the same) and no other mechanical problems either. The photo in the previous post is just after I'd reassembled it - I got the engine battery out of the locker, cannibalised a couple of short cables from the charging wiring, and tried the starter on the "bench". It worked exactly as it should - including not running when it shouldn't have been.

At this point we were greatly cheered up, knowing that we had a fully-functional starter assembly. Even if there was still some other electrical issue, we'd have been able to jury-rig the necessary wiring to start and run manually and so get home. With perfect timing, Chris announced that breakfast was ready, so engine diagnosis was postponed in favour of sausage, bacon, eggs, beans, some interesting diced potatoes with olive oil and herbs, and a quadruple espresso each.

After refitting the starter and the bare minimum necessary wiring, we did several test starts of the engine, which behaved perfectly. So I refitted the alternator and most of the rest of the wiring (a couple of pieces actually turned out to be redundant, left over from various refits) and things remained ok. There's a lot of wiring crammed into a small space between the starter and the alternator on this engine, and I'm pretty certain that the cause of our problem was something short-circuiting in this area. Probably triggered by my recent re-wire - although I didn't do much in that area and I don't think my new cables themselves were shorting, I would have pushed stuff around a bit and perhaps brought two poorly-insulated terminals closer together. The logical explanation would be a short from something at +12v to the output terminal of the solenoid, as that would spin the starter without engaging the pinion (hence the absence of mechanical damage). However, that terminal was pretty thickly coated in paint, with no burn marks or other signs of power having shorted through it, so I don't really know. In any case, I was very careful when reassembling the wiring to minimise the possibility of shorts, and everything is now working properly, so I'm not going to worry about it further.

Pete
 
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