Auxiliary engine

[Cloudy Bay]

Hi all
Just thinking about cross channeling or Channel Isles hip in a 7 m rib, 250 Hp engine and suspension seats.
Are there any good low profile removable outboard brackets? Also what size auxiliary engines are popular?
Thanks.

[Cloudy Bay]

Sorry- hop not hip!

[Bern Hanreck]

If you were in a bit of bother , wallowing on a rocky lee shore ,in an area of strong tides , would you prefer the outboard to be ( semi ) permanently ready mounted on the transom, with a totally independent fuel supply ( maybe only 25 litres ) , or would you prefer to wrestle with the auxillary , mounting and connecting fuel lines . The general belief is at least 1hp per metre of rib . Most users who have ever actually tried an auxillary bracket believe that they have no place on a bouncing rib ! Other opinions may follow........

[Cloudy Bay]

Agreed. Thanks for advice.

[paintman]

I have an auxiliary (Suzuki DT4 4hp)transom mounted on my current boat - 17' Dory.
Normally used for trolling but I have had to use it in anger on two occasions & on one of those it was a 'need it now!' so I also support the having it ready for use option.
I start it before going out on the first trip of the day.

[mhb100]

I have 2 stroke 15 yam to accommodate yam 250. If your planning on long haul your better going larger but weight is a big issue, hence the 2 stroke. None of the cheap brackets are any good so expect to pay £100 plus for something decent. The reality is your probably better not having aux but cruising in company as even with my 15hp it does not push my 7.2m that quick.

[Bushrider]

I have a 7.2m RIB too and I am fine with a 5hp 4 stroke motor with thrust propeller.
Is 15hp not a bit of an overkill ?
Once you reach displacement speed I personally do not think the 15hp will significantly contribute to speed increase

[mhb100]

I guess it's really all about context. If the purpose is about security crossing the channel and actually having power to get home in some wind and swell then Id not want 5hp, it it was about getting from one side of a local bay to the other then a different matter. My 15 is probably lighter than some 8 HP 4 stroke. If I was choosing an aux again I'd probably go for an yam 8hp 2 stroke as I don't do long haul that rarely takes me more than 10 miles off shore.

[Bushrider]

Just sold my Yamaha 8hp 2 stroke ))
For simplicity and speed getting the aux motor into operation I wanted to have one with integrated tank and option to connect a tank .
Looking at the strong tides around the UK , Scotland etc I anyway doubt that the auxiliary motor in many cases would take me home .

[Last Tango]

I swapped my 2 stroke out for a four stroke so as I could run it from the main tank in the event of it having to be used for an extended time

Down side obviously being, if the fuel supply is the cause of a failure, but if you've got 30 or 40mls to get back even with a six horse it's probably going to chew it's way through best part of 25ltr and carrying that extra 2T fuel just for the aux negates any weight savings made by having a two stroke.

[beamishken]

I swapped from a yam5 with integral tank or external to an 8 with only external weight diferance is negligible but the extra cylinder of the 8 just makes it sound so much happier pushing 7.4m.
2 stroke for me so it can get chucked any which way I want without worry and it wont run off the main diesel tank anyway so still need to carry fuel for it
Might not get you all the way home if on a long journey but will probably get you out of immediate danger and to a place of safety

[Fender]

Originally Posted by Cloudy Bay

Hi all
Just thinking about cross channeling or Channel Isles hip in a 7 m rib, 250 Hp engine and suspension seats.
Are there any good low profile removable outboard brackets? Also what size auxiliary engines are popular?
Thanks.

Not sure a auxiliary will be of any use unless your close to shore. I don't run one ( most boats don't ), if your any distance from your destination with a little wind or stream against you a aux isn't worth bothering with. Personally I'd spend the money on making sure your main engine was 100% reliable - or close too as mechanically possible. Its also never a bad thing to go long distance with a buddy boat or two.
Your outfit sounds more than capable of a cross channel hop, but don't pick a date, pick a weather window

[neil.mccrirrick]

I’m all for self reliance so don’t forget an anchor and the ability to deploy quickly. It’s amazing what panic can do. Once you have got past the “my engine is dead I’m drifting” challenge All will become easier including a pan pan for help and other options like an aux

[beamishken]

Originally Posted by Fender

Not sure a auxiliary will be of any use unless your close to shore. I don't run one ( most boats don't ), if your any distance from your destination with a little wind or stream against you a aux isn't worth bothering with. Personally I'd spend the money on making sure your main engine was 100% reliable - or close too as mechanically possible. Its also never a bad thing to go long distance with a buddy boat or two.
Your outfit sounds more than capable of a cross channel hop, but don't pick a date, pick a weather window

I think your assertion that most boats dont carry an aux is quite wrong. Iirc it is mandatory for a coded boat to carry an alternative means of propulsion, it is also strongly reccomended by most safety organisations.
Whilst you will only make slow progress any progress is better than none. As for making an engine 100% reliable that is impossible engines inherently have many single points of failure which will render the main engine useless
I think we all owe it to ourselves and others to try and be as independent as possible.
Our Rnli is not a free version of the US Sea Tow

[Fender]

Originally Posted by beamishken

I think your assertion that most boats dont carry an aux is quite wrong. Iirc it is mandatory for a coded boat to carry an alternative means of propulsion, it is also strongly reccomended by most safety organisations.
Whilst you will only make slow progress any progress is better than none. As for making an engine 100% reliable that is impossible engines inherently have many single points of failure which will render the main engine useless
I think we all owe it to ourselves and others to try and be as independent as possible.
Our Rnli is not a free version of the US Sea Tow

That's a bit harsh! I'm encouraging getting your boat in the best mechanical condition and running with buddy boats and no, I don't believe the RNLI to be or should be a tow service - your quick to incorrectly judge people

Regarding boats hanging a aux off the back, I spent 20 hours floating this weekend in and around the Solent, saw a 2 or 3 boats with aux's, most of the other hundreds and hundreds didn't!! Oh, BYW the MAJORITY of boats aren't coded

Please go 10 miles off-shore, then try and get back to land against any prevailing condition using a aux - good luck

[Cloudy Bay]

All points taken here. I am very experienced at sea fro racing yachts to offshore cruising, so I know the nav stuff and safety stuff etc but I probably was thinking more so about losing power crossing shipping lanes etc. I think a 6-8 Hp would permit me to avoid shipping if it all hit the fan!

[beamishken]

Originally Posted by Fender

That's a bit harsh! I'm encouraging getting your boat in the best mechanical condition and running with buddy boats and no, I don't believe the RNLI to be or should be a tow service - your quick to incorrectly judge people

Regarding boats hanging a aux off the back, I spent 20 hours floating this weekend in and around the Solent, saw a 2 or 3 boats with aux's, most of the other hundreds and hundreds didn't!! Oh, BYW the MAJORITY of boats aren't coded

Please go 10 miles off-shore, then try and get back to land against any prevailing condition using a aux - good luck

Just because you see boats without aux attached doesnt mean they dont have them stored onboard in a locker etc.
My point about commercial boats needing an aux was intended to illustrate that it is considered essential equipment by the authorities, does that not suggest its sensible for private boats?
It is also suggested that every boat carries a secondary means of propulsion in most lists of recommended safety kit I've read.
Whilst an aux wont get you back at planing speed it will in most instances keep you moving. It may mean you head to a point of refuge in the direction of the weather but thats better than sitting drifting possibly at the wrong angle to the waves and weather
Many small yachts can only make 3 4 or 5 kts under engine and yet travel large distances, many of those yachts use outboards of sub 10hp as their main engines
So the assertion that an aux is pointless is unfounded.

Maybe the attitude in the Solent is different and tows are easier to arrange but up here in Scotland you break down its highly likely the only people to get you out of bother are yourself or the RNLI
I stand by my statement we owe it to everyone to be as independant as possible

[paintman]

Let's not forget that heavy displacement hulls are limited by their design - a 25' at-the-water-line will do a max of about 6.7 knots regardless of how big an engine you put in it.
I don't recall seeing flotillas of commercial fishing boats being unable to get back due to 'prevailing conditions'.

[Fender]

Originally Posted by beamishken

Just because you see boats without aux attached doesnt mean they dont have them stored onboard in a locker etc.
My point about commercial boats needing an aux was intended to illustrate that it is considered essential equipment by the authorities, does that not suggest its sensible for private boats?
It is also suggested that every boat carries a secondary means of propulsion in most lists of recommended safety kit I've read.
Whilst an aux wont get you back at planing speed it will in most instances keep you moving. It may mean you head to a point of refuge in the direction of the weather but thats better than sitting drifting possibly at the wrong angle to the waves and weather
Many small yachts can only make 3 4 or 5 kts under engine and yet travel large distances, many of those yachts use outboards of sub 10hp as their main engines
So the assertion that an aux is pointless is unfounded.

Maybe the attitude in the Solent is different and tows are easier to arrange but up here in Scotland you break down its highly likely the only people to get you out of bother are yourself or the RNLI
I stand by my statement we owe it to everyone to be as independant as possible

Why would you be drifting at all, u don’t use anchors in Scotland???
If it’s deep you use a drouge to keep the boats bow into the weather, if you haven’t one on board make one!

You seem fixated with a secondary means of propulsion, keep your primary engine in tip top order and you won’t need to dig around a locker for a corroded and neglected aux outboard that probably hasn’t been started since last season, that on a good day might push you back to safety before you run out of fuel, the engine conks out or you die of old age

Oh, BTW yachts don’t use any size of outboard or inboard for that matter as there main means of propulsion , what they do is use the tall pointy up thing , you attach a large flappy thing to it and the wind pushes it along , think there called sails, not sure what Yachts use up north, but that’s what they do down south

[Bern Hanreck]

Fender , anchors and drogues are all very well for stopping things getting worse ! However they won't get you to a place of safety or home !