Auxilliary engine

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Frank mellin

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I have a freeman 26 with an inboard diesel engine which is fine but I would feel happier with an outboard on the transom in the event of engine failure.
My question is would a 5hp outboard be big enough to get me out of trouble.
 
Short answer is No - however it depends on how you define "trouble". You might get 2 knots in flat water but have little steerage and be subject to wind blowing you around. You would make reasonable progress holding the boat into wind and waves with 10hp. Outboards are not designed to move boats at displacement speed but at planing speeds so will rev away making lots of froth but little thrust. Better spending the money on keeping your engine reliable. Biggest problem is dirty fuel, so tank clean and good filters are a good start.
 
Tranona said:
Short answer is No - however it depends on how you define "trouble". You might get 2 knots in flat water but have little steerage and be subject to wind blowing you around. You would make reasonable progress holding the boat into wind and waves with 10hp. Outboards are not designed to move boats at displacement speed but at planing speeds so will rev away making lots of froth but little thrust. Better spending the money on keeping your engine reliable. Biggest problem is dirty fuel, so tank clean and good filters are a good start.
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I must say i have completely different experience here .

I had a 5hp yamaha on my previous 24 footer and it was able to move the boat with ease . It was not 2 knots but 4-5 . Steering was obviously not so comfortable sitting with the tiller on the transom but in any case absolutely sufficient to keep course and manouver into a harbour .

So yes , a 5hp will do the job to haul a 24-26footer into next harbour from situations you would use the boat normally .

That may exclude gale force winds and waves in open north sea but its not very smart to move out in such conditions at all .

Needless to say the kicker engine should be a reliable starter and take into account to carry extra petrol since the internal tank will not last longer than ~1 hour at full power.
 
Select a "High Thrust" or "Sailpower" motor - these have a larger gearcase, lower gear ratios and a high thrust low speed prop. They are designed to move larger heavier boats like sailing boats at lower speeds rather than as above stated small boats at high speeds.....

As long as you are happy to make 3-5 knots which is all you will get no matter what size the engine (unless you fit a 300hp) because to get close to hull speed you'd need that kind of power - but the power you need to go that much slower is massively less. Remember they used to haul massive barges along canals with just one horsepower - at about 1-2mph.
 
Tranona said:
Short answer is No - however it depends on how you define "trouble". You might get 2 knots in flat water but have little steerage and be subject to wind blowing you around. You would make reasonable progress holding the boat into wind and waves with 10hp. Outboards are not designed to move boats at displacement speed but at planing speeds so will rev away making lots of froth but little thrust. Better spending the money on keeping your engine reliable. Biggest problem is dirty fuel, so tank clean and good filters are a good start.
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As above - not quite true.

Standard outboards are designed to move boats at high speed - but there are High Thrust or Sailpower motors which do the opposite and push heavier boats slowly.
 
ontheplane said:
As above - not quite true.

Standard outboards are designed to move boats at high speed - but there are High Thrust or Sailpower motors which do the opposite and push heavier boats slowly.
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While the high thrust engines are better than standard this is still a very heavy high windage boat and 5hp would still be limited. The OP does not day where he uses the boat, but it is primarily an inland waterways boat so one might question why the need for a second engine anyway. There is also the question of how you would control i given the shape of the aft end watersidemarinesales.co.uk/boat/freeman-26-cordwainer/
plus the need to carry petrol when the main engine is a diesel.
 
billskip said:
It's a flat transom, easy to fit an ob bracket

Most diesel boats have tenders, what fuel do they use?

Stop wriggling...
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Electric outboards are common now to avoid petrol. An 8-10hp outboard that would provide some usable performance would require a remote tank, be heavy and the powerhead with controls would be difficult to reach from the cockpit.

My argument is whether there is any need for an auxiliary at all. A light 5hp would not give much usable power (and still be difficult to operate) and an 8-10hp would be enough but at further additional complication weight and cost.
 
For the expense and hassle of fitting an outboard and controls (as I've recently found out) it'd be a better bet to give the engine/drive a big service, clean out the tank and fit a fuel polisher - aesthetically better, only one fuel on board, and no sticky outy outboard when parking.
 
Frank mellin said:
I have a freeman 26 with an inboard diesel engine which is fine but I would feel happier with an outboard on the transom in the event of engine failure.
My question is would a 5hp outboard be big enough to get me out of trouble.
Click to expand...
I had a 22ft Guy Couch with an inboard diesel, on the transom was hung a 9.9 Evinrude. I tried the boat on Winderrmere on the outboard only and it did not do 5 knots. Perhaps the big 4 blade inboard propeller caused a lot of drag. I could have improved the engine from 9.9hp to 15 hp by fitting a bigger carburettor as the 15hp is the same engine.
And no I dont think a 5 hp would get you out of trouble (unless you were on an inland waterway.
 
I know that you would not use one. But would not a Seagull Century push the vessel at an adequate emergency speed. It would not be required for long distances because it is an emergency situation. The fuel tank is integral with the engine & the long shaft big prop will provide lots of low torque.
 
Interesting… Our cousins across the pond have a different view, many wouldn’t dream of going offshore without a specialist “Kicker Motor”! These boats often go miles offshore and use the Kicker extensively for trolling and as a get you home “just in case”. … Just saying??
 
moresparks said:
Interesting… Our cousins across the pond have a different view, many wouldn’t dream of going offshore without a specialist “Kicker Motor”! These boats often go miles offshore and use the Kicker extensively for trolling and as a get you home “just in case”. … Just saying??
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Those "kicker motors" are the high thrust versions, lots used for trolling lakes and rivers while fishing.
Some chart plotters allow integration of the e-motors and to be able to steer the motor from the plotter, I know it is an option on the Garmin Echomap that I have to be able to link to the Garmin electric trolling motor.
 
Thanks for all the replies much appreciated.
Have another question.
Have managed to find a suzuki engine and have now fitted it to transom on the outboard bracket that I purchased.
Attached the bracket direct to the fibreglass surface and added an internal plywood fpanel or extra strength.engine still feels a bit fragile on the bracket.should I attach a thick panel to exterior of transom and attach the bracket to that
 
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