Hi all,

I've just purchased a Dolphin 19 for restoration, it has been in a shed for 30 years so it is structurally quite sound.

My problem is that I have always had a pathological hatred of outboard motors so know very little about them! Are outboards power output expressed in different Horsepower than inboards? I ask because my Albatross has around 100 BHP and by that token the Dolphin should need about 150 BHP!

Can anyone advise on what sort of power I would need, I don't want racing performance but do want a brisk planing speed, say 25 ish knots?

Pre '84 outboards were BHP,post '84 SHP. The conundrum is that the change over occurred over a couple of years between '82 & '84.Merc anyway.
There should be a plate on the Dolphin stating the max HP, but I think a 80BHP or a 70SHP should push it along rightly.
Of course if you want to cruise the rivers a smaller engine would suffice. I'm basing this on the fact I haventaclue what a Dolphin 19 looks like but I have a '69 80BHP on a 17' fiberglass copy of a Maxum 17 and it pushes along at about 33knots

haventaclue wrote: I haventaclue what a Dolphin 19 looks like but I have a '69 80BHP on a 17' fiberglass copy of a Maxum 17 and it pushes along at about 33knots

Thanks for that haventaclue, this is a Dolphin 19 from the 1960s

60s boats have very different handing characteristics than modern hulls. I know, having nearly gone to DJL in a small hard chined runabout with tumble home (which the Dolphins have) & a small-ish motor at high speed. There are a number of internet sites with length x transom factors vs hp which might help. This is one but I'd advise a similar era table rather than modern CG ratings. Bear in mind up till about 1962 , 60 to 70 hp was the biggest motor one could readily buy. This would have been horsepower at powerhead rated, rather than hp propeller rated, hence you may see an '80s 4 pot Mercury (44 cu.in) called a Classic 45, yet when rated in 61, might have been a 50hp (hence 500), yet both are the same 44 cu. in. capacity (as is the 1960 400, but that's another story...)

http://newboatbuilders.com/pages/hp.html

P.s plenty of converts to outboards here...

http://www.jonesboatyard.co.uk/documents/Dolhin-19.pdf http://www.jonesboatyard.co.uk/documents/Dolphin-19.pdf Max 40HP or 60hp.And I'm thinking that would be BHP .80HP would have given you a white knuckle ride.

I hate to put a damper on your thoughts , and I am a big fan of the 80/85 hp mercury but I think it may be a little to powerful for a Dolphin 19 that could be the best part 50 years old, as Rapier has said, motors of that size were not common in the U.K. back then and the boat is flat bottomed , with that size of motor on a ply wood boat that age that was not designed for that sort of power, you could spend a lot of time glueing it back together when the joints open up as it all moves about at speed..!!......and it will.

Thanks for all your helpful comments!

I was thinking that a 50Hp Evinrude e-tec would be a good choice?

My 80 BHP is rated around 68 SHP, so a 50 SHP would get you close to 60 BHP which is the max for the 19' Dolphin

Sea-Jay wrote:Thanks for all your helpful comments!

I was thinking that a 50Hp Evinrude e-tec would be a good choice?

I like them; a modern 2-stroke to beat the hype and weight of a four stroke with green credentials. Retro styled cowling means they're easier on the eye than 4-stroke blobs too - whatever happened to outboard cowling design? Most have a self-winterising process that needs careful attention not to activate inadvertently .