Choosing replacement outboard

[Keylime 0]

Hi,

I need to replace the outboard for a more reliable one on my 20" trailer sailor. This is a 1974 6HP Johnson short shaft. Would I be advised to go to a long shaft? I'm in Wellington where it is quite windy - what size outboard should I have?

[harrytom 697]

4 stroke Honda 6hp very quiet.not sure of price.

[El Toro 115]

I had a 5hp Honda... never again.

Yammy all the way

[Steve Pope 253]

Stick with what you have got. So long as it runs ok, why change it. A 20 year old outboard is not much different to the latest models. Motor turning a propellor, that's all. Go out sailing and see how good / or bad all the bits you want to change really are, (service them first) you might find you could have a better spend on a new main and, or, jib. If the ones you have are seen better days.

[aardvarkash10 1,105]

1974 means its coming up to its 50th birthday.  If its unreliable now and you don't know its history, Its a gamble to keep using it - it will fail at the most difficult time in your sailing life for sure.

this article sets out a formula for sizing.  I'd go a step bigger in Wellington given the likelihood of "difficult" conditions.  Here's some more thoughts directly targeting your boat size.

I would be balancing weight and portability against thrust as key factors.  In that size range and leaving some of the questionable cheap options to one side, simplicity is probably more important than fuel efficiency.  So that gets me to a name brand two-stroke long shaft at 4 - 6hp. YMMV.

 

 

[jim s 34]

The bracket is mounted quite low on the transom so you may get by with another short shaft if good one was found at the right price. our 20' has a yamaha 8 thats been to the moon and it's still easy starting and reliable, plus the two strokes are a fair bit lighter than the four strokes...

[eruptn 105]

After 30 yrs in trailer yachts, the most important consideration is the prop on the bottom.. a suitable sail drive version. Next step would be long shaft for transom installations. I've always had 2-stroke, but the 4-strokes are making a impact. Motor size is dictated by the Part V safety regulations for trailers yachts: "Motor rating shall be a minimum of 0.6 kW per metre overall length (approximately equivalent to 0.25 hp per foot of overall length)"

[Keylime 0]

Thanks for the comments. Great to see the divergent opinions on whether to replace! I think I'd like to upgrade, eventually to do a Cook Straight crossing without freaking out.

I’m looking at 2 outboards now - 2 stroke Mercury 1995 8HP Short Shaft $500, or 4 stroke Yamaha, long shaft, 6HP, 2015, $1600. Any votes for either of these?

 

[Island Time 1,294]

Positioning the outboard low is a risk. Higher and long shaft is safer.

Once, long ago, I had an Alan Wright Pacer (24ft) trailer yacht. In cook strait, in strong conditions, trying to get into Tory Channel, several times the outboard was completely immersed by following seas - I would not have wanted one mounted any lower! Yes, fortunately it kept going! It was a long shaft mariner. Also, as the motor is mounted right aft, they are prone to lifting props out of the water when choppy.....

[Keylime 0]

14 minutes ago, Island Time said:

Positioning the outboard low is a risk. Higher and long shaft is safer.

Once, long ago, I had an Alan Wright Pacer (24ft) trailer yacht. In cook strait, in strong conditions, trying to get into Tory Channel, several times the outboard was completely immersed by following seas - I would not have wanted one mounted any lower! Yes, fortunately it kept going! It was a long shaft mariner. Also, as the motor is mounted right aft, they are prone to lifting props out of the water when choppy.....

Thanks for your comments. Any advice on the motor size?

[Island Time 1,294]

A 6hp 4 stroke should be fine, we had an 8 on the pacer. You might want to change the prop to a lower pitch and large blade area for more thrust. 

[eruptn 105]

7 hours ago, Keylime said:

Thanks for your comments. Any advice on the motor size?

Motor size is dictated by the Part V safety regulations for trailers yachts: "Motor rating shall be a minimum of 0.6 kW per metre overall length (approximately equivalent to 0.25 hp per foot of overall length)"

[Deep Purple 530]

 I'm impressed with my 6hp Suzuki 4 stroke even though it's .2hp short of the nztya rule. Pushes us at 8 knots full speed and a lot of bite manoeuvring. They had a deal going at $1999 might still. Lightest 6hp 4 stroke

[Keylime 0]

28 minutes ago, Deep Purple said:

 I'm impressed with my 6hp Suzuki 4 stroke even though it's .2hp short of the nztya rule. Pushes us at 8 knots full speed and a lot of bite manoeuvring. They had a deal going at $1999 might still. Lightest 6hp 4 stroke

Thanks for the tip. I’m in the shop looking at the 6HP Yamaha 4 Stoke 2014- $1600. It’s in great condition, but up against a brand new Suzuki I’m not sure which to go for.

[Addem 121]

4 hours ago, Keylime said:

Thanks for the tip. I’m in the shop looking at the 6HP Yamaha 4 Stoke 2014- $1600. It’s in great condition, but up against a brand new Suzuki I’m not sure which to go for.

Make sure you discuss the prop. Not all props get the boat moving backwards. We put a high thrust on our Yammy 9.9 and it transformed it. 

[Gappy 9]

11 hours ago, Deep Purple said:

 I'm impressed with my 6hp Suzuki 4 stroke even though it's .2hp short of the nztya rule. Pushes us at 8 knots full speed and a lot of bite manoeuvring. They had a deal going at $1999 might still. Lightest 6hp 4 stroke

Yup they are still on special too don't know why you would waste time on a second hand one at that price and a new 5 yr warranty. I have a suzuki bloody love it. 

[Keylime 0]

3 hours ago, Gappy said:

Yup they are still on special too don't know why you would waste time on a second hand one at that price and a new 5 yr warranty. I have a suzuki bloody love it. 

Yup have decided to get suzuki 

[Black Panther 1,767]

22 hours ago, Deep Purple said:

 I'm impressed with my 6hp Suzuki 4 stroke even though it's .2hp short of the nztya rule. Pushes us at 8 knots full speed and a lot of bite manoeuvring. They had a deal going at $1999 might still. Lightest 6hp 4 stroke

Wow . BP can't motor at 8kn.