Outboard or Inboard

[MelF]

Hello,
I am based in Victoria and always looking for the next best thing yacht wise. Currently have an 18' Trailer Sailer.
A quick question please: is the inboard diesel the standard form of power and has been replaced by an outboard in some boats, or was the outboard always a power option?
Can an outboard power the boat sufficiently into a strong headwind?
Thanks all,
Mel

[Miker]

Welcome Mel,

You're going to get both sides of the story here on that point. Do a search on this and you'll see a few topics on it.

In my opinion, in short, a diesel is always better, however if you're looking at a Top Hat with an outboard, don't let that be the only reason to turn you off it.

The outboard option was always available from Mark 1 all the way through. Originally, a transom mount on the Mark 1, but a well was put in for the Mark 2 and 3. I have mine over the back on a lifting bracket on the transom. It's not perfect, but the boat was cheap and the system works. I've pushed into 30 knots in the harbour, and motored for 6 hours between The Entrance and Pittwater into a southerly swell with no wind.

Have a look around, you'll find a variety of stories.

[Ianb]

Hello Mel! Now we know what you are thinking. I feel a little disloyal to my Investigator 563, however I have lusted after a Top Hat ever since I had her baby sister, the Bluebird 22.
Anyway, back to your topic. Have you read viewtopic.php?f=3&t=951&p=5335&hilit=diesel#p5335

It is not that outboards have superseded diesel inboards, it is just that inboards are more expensive initially, and it would be uneconomical to fit an inboard to a current boat that does not have one. Diesel advantages are less fumes, lower noise, can plug on forever. So if you were doing long offshore trips, having a diesel would be good.

An outboard in a well, IMHO, based on my experience with the Bluebird and the Investigator, is that a well mount is far superior. There are no problems with cavitation, and you can easily get to the motor to de-bug if it starts to play up. CF with an OB on a transom bracket, once on the Investigator cavitation in choppy confused seas caused the shear pin on the propellor to fail, and there was no way I could get to it to fix it at sea. In a well it would have been a breeze to pull out.

WRT thrust, the key issue is the correct choice of propeller. For the same HP rating, the thrust will be the same, diesel or outboard. From what I read here, outboard power is limited by what will fit in the well, but I guess 6 to 8 HP should be enough.

[Troppo]

Hi Mel, the thread given in IanB's post has good info. You asked a specific question about can an outboard power into a strong head wind. I would say it depends on the strength of the headwind and the HP of the motor. The PO of Windchaser took out he 9 hp and put in an 18 HP 2 stroke as he wanted heaps of punch for going against big seas. The 18 hp certainly does that! He had to make the standard TH well bigger to fit it. Coming up the coast of Qld with Windchaser after I bought her a month back, I found the 18 horses to be waaay more than I needed. The thing to remember is that these displacement hull sailing boats are not like tinnies since more power does not make for more speed. However, when more grunt is needed against waves and wind then that extra power is useful to get up to the normal cruising speed, which for me is 5 to 7 knots depending on how much of a hurry I am in.

My previous boat had a sickly 1GM10 (diesel) with about 8 hp. Add a couple of small barnacles to the prop and I got 3 knots max. Polish the prop and I got 5 to 6 knots on calm water. I love diesel motors and was happy having plenty of cockpit space however, the 18 hp outboard on my new boat did sterling service coming up the coast. In fact, coming over the Wide Bay Bar to get behind Fraser Island with some 3 metre breaking waves then serious washing machine stuff I was glad of the extra zoom available.

So, while there are obviously major differences between a diesel inboard and petrol outboard both types of motors can satisfactorily do their assigned task which is to get you out sailing.

[Killick69]

We are happy with our 8hp, 2-stroke Tohatsu in the well. Would love to know if the well in the cockpit was built in at the time the boat was built (certainly looks good), as the boat at one time had an inboard. Only concern I have is that the inboard locates prop a lot lower than the long shaft outboard in the well can. An extra long shaft outboard in the well would be great. I don't think more than 8hp (2 stoke) is needed. One day, just for fun, I am going to try the short shaft 3.5 Tohatsu (my outboard motor) in the well.

[SeaLady]

I am very happy with my 8HP Mercury.
It has been fitted with a sail prop which gives more thrust especially in reverse.
And a charging thingy to recharge batteries whilst it is running.

It has pushed me into a 45 knot head wind in Sydney Harbour with waves crashing completely over the boat and 5 metre waves outside.

Easy to lift out of the water, store, maintain, cheaper to buy and replace than an inboard.

[storm petrel]

If you can afford it, get a diesel. More torque, weight down low and you only have to turn a key to bring the 'iron genoa' into play. Storm Petrel has a 14 HP Yanmar twin and it is enough to push her along at 5 knots in most conditions and only uses about 1 litre of fuel an hour. But yes, you do need to keep the prop clean.

Cheers,
Mark

[MelF]

Thanks everyone, I appreciate the responses. A lot to think about.
Ian - I don't think you disloyal at all. The Investigator is a fine little ship, it makes sense that you would consider another fine little ship when upsizing. Both boats have such great pedigrees and are solid, 'honest' boats, it that makes sense...
Cheers all - a great forum.

[Killick69]

On issue of the outboard is the water that sits in the recesses in the cockpit. Instead of water draining out aft, the lack of of weight without the inboard means the water ponds towards the companionway.

Diana, the charging circuit on the outboard is one of the things on my list. How effective is it? I have found the 40 watt solar panel and one lead acid battery adequate, but wonder how the battery will hold up if I was to motor/sail at night with nav lights on. Would hate for battery to give out.

John

[SeaLady]

Hi John,

The answer to your question as to how effective the charger is from my outboard is difficult for me to answer as I have had this discussion with many people including my dad who is a retired electrician.

Suffice to say from my non technical viewpoint. i.e no amphours, volts, ohms etc

Yes it give me enough power to run my TV / DVD player.

When staying overnight in winter with my old battery and watching movies.
After 1 and a half movies the battery was too flat to work the player.

Running the outboard for the 2nd half of the movie enabled me to watch the movie, have lights (incandesnet - now being replaced with LED) and have enough power in the battery to run radio etc the next morning before the solar panel took over.

My dad, retired electrician has tried to explain it to me technically, as have other technical people and they have measured the charging with a meter and shown me but I have not understood what they are telling me.

Suffice to say with the outboard running everything electrical works, even with a flat battery.

Does that help?

You are welcome to come on board and make measurements.