Engine for Walkerbay Genesis 340?

[fireball]

We have a Walkerbay Genesis 340 that we used as a tender to our big boat - it ran ok with a 2.5hp outboard, but not very fast.

we now want to use the boat as a coaching platform for the tiddlers in the family who will be sailing around in Optimists and as a general transport boat down the harbour - plus as a tow boat when the wind dies ...

As we're in Chichester Harbour there's a speed limit of 8 knots that we need to adhere to, but with the 2.5hp we're lucky to get 4kts!

So, what I'm after is some thoughts as to a suitable engine. I know Emsworth Chandlery run a 20hp on the back of theirs but as we have to launch/recover by hand on a slipway I want it still handleable by one person.
Would 5hp provide enough grunt or should I look to 8 or even 9.9hp? I would like it to be able to plane with 1 adult and 1 child on board (ie in an emergency)

I'm thinking that above that it's not worth the cost or weight given the restrictions above ...

Thoughts?

 

[TQA]

With a clean bottom an 8 hp will plane 2 people.

Check the weights of 15hp ob many are with in a kilo of the 9.9.

Most people use some kind of OB hoist. I can easily fit and recover my 18hp on my own.

 

[fireball]

I'm looking to use this as a stand-alone boat - nothing to do with big boats as we don't intend to have ours much longer ... (want a Bav37 shoal keel? )

8hp planing 2 people is good to know - the boat will always have a clean bottom as it doesn't live in the water ... so it'll be interesting to find the weight difference between 8 and 9.9hp ..

ta

 

[Nick_H]

If you're spending a long time out on the water, mix of speeds including lots of slow speed, then I think 4 stroke is better than 2.

The problem is that 4 strokes don't plane as well, so I think you want at least a 10 hp, but then a 20 hp is only a few kgs more and will be loads better, so i'd go for the lightest 20 hp you can find. I found this site useful for comparing the weights of different outboards http://outboards.findthebest.com/

 

[fireball]

thanks for that ... that weight comparison is good ...

we're not looking to spend loads so a s/h 2 stroke may be on the cards if I can find one. I've also got to consider that young kids may get to have a drive - ok on a wheel steer, but easier with a small outboard on tiller steer.

 

[landlockedpirate]

I think if you are going small, a 2 stroke is the way to go. The Yamaha 8hp weighs 28kg, it's a great engine and should get you on the plane as mentioned above, I doubt anything less will. The yam 9.9 is the same weight as the 15 at 36kg, it can still be picked up, but it's getting to the limit of what you want yo carry on your own. The holy grail of tender engines is the Tohatsu 9.8hp at 26kg it's easy to move around and bullet proof.

Be aware, the value of good used 2 strokes is going through the roof. You are looking at £800-£1300 for a good example of any of the above engines.