Small outboard and charging ?

paulburton44

paulburton44

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www.withamsailingclub.co.uk
I've been looking into small outboards that will push a 21 foot trailer along. I guess 4-5 hp would be fine. But not many seem to have a charging coil.

Honda 5 does and the Tohatsu sail 5hp does....

Any other recomendations.
 
Showing my lack of experience with outboards..., my Honda 4.5 (a lower emissions 5) has a generator. Does this connect directly to the battery or do you need to regulate it somehow, and put a fuse in somewhere along the line.

This engine pushes my Dehler 22, but I have wondered how it might cope in tidal conditions...there's can't be much spare oomph can there.

Tim
 
Mines an Evinrude 6hp, longshaft, sail version.

I would not go below 5hp, rather go bigger. I know you cannot go faster than the hull speed but there are times when you want to be able to do that against a strong wind or a nasty chop.

Long shaft is vital so that it can be mounted with the prop low so that it does not keep coming out of the water in a chop.

Look at what props are offered. Ideally you need a fine pitch for a displacement hull. Mine has a finer pitch, a larger diameter and a huge blade area compared with the standard 6hp version.

Mine also has a built in rectifier for direct connection to the battery. Check the cost of a rectifier/lead if the rectifier is not fitted as standard.
Also look at what the electrical power output is. Some, mine included, are pretty pathetic AND if it is just a rectified output from a lighting coil you'll find that the quoted output is the maximum which you only get at full revs. You'll seldom want to run it at full revs so will get very little useful power and even then only if you motor more than you'll want to

So I also recommend a solar panel, mines only 5W.

Also consider the weight, a trade off against hp I know. Especially as you'll be lifting it on and off regularly. I used to stow mine in the cabin when not in use but it has got far to heavy to do that now, in fact in a little over 20 years it has almost become to heavy to lift on and off the bracket while ashore!

Sorry not exactly answering your question but all I've had is the Evinrude and a Volvo Penta
 
You won't want a long shaft motor with a motor in a well like a Parker 21 - standard shaft is as good as it gets and will ground first with the keel right up. I get a bit of charge at full throttle on my Merc 5 but practically nothing at sensible revs. I have great hopes for the 10w Solar Panel I've just installed from www.sunshinesolar.co.uk .
£50 through their E-bay shop or £10 more direct!
 
Last season I bought a Tohatsu 6hp 4 stroke long shaft; without charging coil. The engine is very good, solid, light and always start first time (so far). I recomend it. Fit a small solar panel to keep your batteries toped up
 
My suzuki 4 hp 4 stroke had a charging coil and rectifier fitted .The output was connected direct to the battery through a plug and socket .

I motor half a mile to the locks every time so it regullarilly topped up the battery and in 3 years never charged the battery by any other means. You do need to be frugal with power use and my boat didnt have a tillerpilot .

The 4 hp pushed my Anderson 22 at 5 knots in calm water. if you motor a lot possibly a 6hp would be better.Depends on the type of sailing you do.

The engine had a short shaft and was mounted in a cockpit well. It never gave any problems with prop lifting out etc but different boats need different shaft length so try and ask an owner of the same design.
 
A 10W panel for 10 pound would be very good price indeed. I think really a super special might closer to 60 or 70 squid.

The older outboards used to have what they called a lighting coil. It was designed to drive nav lights direct on AC. If this was used as a battery charger then the rectifier would reduce this voltage so much that charge was quite small. My old Johnson would give about .3 amp at cruising revs. That is a lot less than a 10w solar panel will give.
This kind of current doesn't need a regulator on any decent sized battery. Some newer outboards may do better at charging. But don't count on it.
I use a small 5w solar panel exclusively for charging on my 21fter. But that is in Oz summer sun. We actually had some cloud yesterday.

good luck olewill
 
I too looked into whether it was worth trying to charge from the outboard but concluded the output wasn't enough. I have a 30W solar panel, two 85amphour batteries, and yet to have any problems. The boat is also an Anderson 22, and I've got a 2 stroke Yamaha 5hp which seems to have adequate power.

Solar panels are great for weekending, you can run the voltage down (last week had the cool box going on it for first time) and when you back following Friday it's fully charged again. However not so useful if spending a week or two aboard.

IanC
 
We never bothered connecting the 8 hp outboard to the battery on our 25ft, 85ah battery boat and have managed well with a wind generator and a portable 10W solar panel and our family of 4. I also carry a battery charger which we can use in a marina if we have to. So far never had to in anger. I am considering carrying an extra battery this year. We normally spend every other summer weekend on the boat and go off for around 2 weeks in the summer usually.
 
I agree I have a honda 5 (came with the boat) and I suspect there are better motors out there. The charging is minimal for the amount of use it gets. As I have suffered a dead battery I am intending to fit a battery charger and shore power connecter so that I can stick it on charge at the marina. If you do not have shorepower then wind seems to be the best but most expensive alternative followed by a solar panel.

My problem with a solar panel is where i would mount it as I have a flush decked boat with no coach roof.
 
No £10 more i.e.£60 - Actually I just looked at the site again and they're now £65. It's the monocrystalline type. I think they're much more efficient and my battery often gets up to 15v so I run the nav lights now and then (boat in front garden!).

Can't find them on Ebay at the moment but there are similar ones there.
 
most of these very small outboards with a power take off do not regulate the power very well, and it is designed purely to be able to power a set of nav lights. Not enough amps for anything worthwhile.
 
If you want a reasonable altenator output that can run a boat's 12V system from an outboard, you need to go a bit bigger. The 6hp Honda and the 8hp Yamaha are the smallest to have a proper charging capability (5A and 6A respectively) from those manufacturers. The output gets more for the bigger models. All details on their websites.

I've had a 6A altenator output Yamaha 9.9 for years now, and it's fine for my needs. Connect it straight to the battery and go. Regulator/rectifier all standard equipment and built in.
 
swampthing said:
Has anyone tried those chinese copies of the small quiet Honda generators. I saw em on ebay. Think about 500w. £160
Click to expand...

Yes, I bought a 1kw one for about £180. Lasted for about 3 hours running time , then died. Unfortunately, it was out of warranty and local repair shop decided it could not be fixed. I replaced it with second hand Yamaha of the same spec at about the same cost and it has been perfect.

I use it to top up batteries when the solar powe is struggling with demand.
 
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