engine horsepower

[stuartgsd14]

New to sailing so forgive my novice questions but have been looking at a few cruising yachts one that i like has a 10hp bukh engine would this be enough to push along a 26ft nearly 4 ton boat,not in a hurry but thinking more about having plenty of power for getting out of trouble.Do different engines tend to drive boats better than others.
help appreciated

 

[Reverend Ludd]

New to sailing so forgive my novice questions but have been looking at a few cruising yachts one that i like has a 10hp bukh engine would this be enough to push along a 26ft nearly 4 ton boat,not in a hurry but thinking more about having plenty of power for getting out of trouble.Do different engines tend to drive boats better than others.
help appreciated

10hp will be ok, maybe a tad underpowered but probably average for a 26ft sailboat.

 

[Reverend Ludd]

Oh and welcome

 

[Twister_Ken]

I had a 10hp Bukh im my 28' 4 ton* Twister. Absolutely fine. 4.5 kts at comfortable revs, 5.75 kts at full chat.

*Design weight. She as probably at least half a ton heavier with all the kit aboard.

 

[Tranona]

Very popular engine in its day and adequate as an auxilliary. More likely if fitting an engine to that size boat now you would choose one of the newer 14 or 16hp 2 cylinder engines. Smaller physical size but more powerful quieter and smoother - at a price.

26footer will have a maximum speed of under 6 knots and a cruise of between 4.5 and 5. The Bukh will achieve that.

 

[penfold]

Plus you'll struggle to buy an auxiliary as small as 10hp these days; I can't think of any smaller than 15hp.

 

[satsuma]

10hp on a 26' boat is more than appropriate, I would suggest! About 30 or 40 years ago, it would probably have been about 6 or 7 hp!
My Hustler 25.5 has a vetus 11hp, with a folding prop, she will push to 7kts, at full power,and comfortably makes 5kts at about 65% even against the wind in the corinth canal!

 

[Babylon]

10hp on a 26' boat is more than appropriate, I would suggest! About 30 or 40 years ago, it would probably have been about 6 or 7 hp!
My Hustler 25.5 has a vetus 11hp, with a folding prop, she will push to 7kts, at full power,and comfortably makes 5kts at about 65% even against the wind in the corinth canal!

There is a little more to the equation however. Its not just boat length, its also to do with displacement and keel profile. EG the appropriate engine power for a Vancouver 27 (long-keel, heavy-displacement) is at least 18-20hp. A lightweight, fin-keel cruiser-racer of the same length might only require half that in normal conditions.

And it depends on the use and conditions. If the engine is intended merely as a means of propelling a similar length racing yacht on the final run back into harbour, then a 3.3hp outboard will suffice. If its a question of propelling a long-distance heavy cruising yacht continuously through calms or motorsailing in rough conditions, then a powerful inboard engine will be less wearing, hour after hour, at 50% revs than a smaller engine up at 85% revs. (Modern diesels are apparently far more tolerant to being run at only medium revs compared to older designs.)

I could have re-engined with a 20hp engine in my Vancouver 27, but in the end went for a 25hp on the basis that the Solent and English Channel are my main cruising ground - the usual short chop frequently stops my small but heavy boat dead in the water - and I wanted the reserve power, especially if I was doing this over some distance up or down Channel.

Other owners though have re-engined with 20hp and this is more than adequate. So my extra power is a bit of a luxury, because in normal conditions our hull-speed is limited to 6.0kts max under power (although we regularly exceed 7.0kts under sail in a stiff wind in relatively smooth water) and things are quieter and less wet if we motor at just 4.5-5.0kts.

 

[Davy_S]

Plus you'll struggle to buy an auxiliary as small as 10hp these days; I can't think of any smaller than 15hp.

Beta 13.5 for a start!

 

[Poignard]

I had a 10hp Bukh im my 28' 4 ton* Twister. Absolutely fine. 4.5 kts at comfortable revs, 5.75 kts at full chat.

+ 1

I have a 10hp BUKH in my Twister. I once motored in a flat calm all the way from Cherbourg to Gosport in company with another Twister fitted with a BUKH 20hp and found my boat was very slightly faster!

Several Twisters have the Yanmar 9hp engine and seem to be adequately powered. If I ever need to replace my BUKH engine I will go for a Yanmar 9hp because it's simple, light, compact, well-proven and has a starting handle.

*Design weight. She as probably at least half a ton heavier with all the kit aboard.

Good estimate! Last time I had my Twister craned out she weighed 4tons 10cwt (according to the gauge on the crane) in full fighting trim.

 

[doug748]

As others have said, 10hp is fine.

On the face of it a large engine seems a good idea.

Beware of boats with over large engines though, they may be too heavy for the boat, too powerful to turn a suitable prop and be running under speed most of the time.

This tractor size engine is often fitted because someone got it cheap "off uncle Jack" and may be unsuitable in other ways. Remember a saily boat has a pretty fixed top speed under engine and any excess is generally useless. I would try and find an engine known to the marine market, like the Bukh.

 

[Poignard]

Another advantage of BUKH engines is their longevity. At 29 years-old, mine is a mere youngster.

 

[Tranona]

Another advantage of BUKH engines is their longevity. At 29 years-old, mine is a mere youngster.

Think that is true of most marine engines now. Replacements are in 30 year old boats, but the new engines I would suggest will last at least as long if not longer. The mechanical bits have a life of 8000+ hours (average yacht hours 100 pa!). It is the bits attached which give problems, but in moden boats these are at least kept warm and dry, so if the engine is used regularly, always run up to operating temperature and oil changed regularly, 30 years life should be easy.

I took my Yanmar 1GM out at nearly 20 years old and it is now in another boat ready to do another 20 years. Only replaced because it was marginal on power and a Nanni or Beta 14 is superior in everyway for the same physical size.

Hope Yanmar keep making the 1GM as it is a brilliant engine for some boats, but there are few new boats built that use it - and the 2 cylinder 10hp engines are very little more money.

 

[Daedelus]

I used to have a Moody 31 which had a 28hp engine and I thought this a little excessive. I happened to mention it to one of the Moody engineers who confirmed they had bought a job lot of 28hp engines cheap and were putting them in any boat they could without much regard to need.

So don't think that because someone has a much more powerful engine it was necessarily needed.

 

[Spyro]

Plus you'll struggle to buy an auxiliary as small as 10hp these days; I can't think of any smaller than 15hp.

Yanmar 1GM10 still being produced

 

[jwilson]

New to sailing so forgive my novice questions but have been looking at a few cruising yachts one that i like has a 10hp bukh engine would this be enough to push along a 26ft nearly 4 ton boat,not in a hurry but thinking more about having plenty of power for getting out of trouble.Do different engines tend to drive boats better than others.
help appreciated

10 hp a reasonable size, though many now fit bigger to 26 ft boat. Bear in mind that a bigger, more powerful engine will mean a bigger prop which will add drag and reduce your sailing performance.....

I used to have a bigger, heavier boat with 7 hp, and when it was working it was fine, though a little more would have been better under power.

 

[BurnitBlue]

Eric Hiscock in Wanderer III circumnavigated twice plus and Atlantic circuit with a 4hp Stuart Turner Two-stroke.

But then Eric and Susan Hiscock were sailors.

 

[Supine Being]

I've got a 10hp BUKH in my Sadler 26 and it's absolutely fine. I've not had the boat very long, but no problems so far and the previous owner tells me that she'll plug along all day long - I've no reason to doubt him. The only thing I will say is that it's slower to rev up than I've been used to, so I've been unable to use prop wash in marinas where I've been able to on larger boats. Or maybe I just need to get to know her better

 

[Poignard]

The only thing I will say is that it's slower to rev up than I've been used to, so I've been unable to use prop wash in marinas where I've been able to on larger boats.

Yes - there's lot of inertia in that big flywheel. When you tell it to speed up it likes to have a little think about it first!

 

[Clyde_Wanderer]

My boat has a 16-18hp 3cyl perkins running a 13"x 8 pitch 3bladed prop. Her displacement is 3.2 tons and she is a long fin keel (6-7ft long) her hull profile is identical to the Elizabethan 30. her max speed under engine is 5kts in slack water, but when punching into any choppy she struggles to top 2-3kts and can very easily fall far behind when in the company of a Snapdragon with a 1GM10 and a Foxhound with a 15hp outboard, although she can easily outrun them under sail.
Why is she so sluggish under power, could she be under proped, needing more pitch, or under powered>
I have been told that if an engine (Diesel) does not give an initial puff of smoke when fully opened up then she is under proped.
What does the board think?
C_W