Outboard for '59 Whirlwind

Hi, New to forum. Looking for advice on good engine for '59 Whirlwind wooden runabout I've redone. This is 17.5' hot molded construction, 7' beam with no internal framing other than seat mounts and floor stringers and so is very lite; about 800 lbs. load capacity is about 1600 lbs. Flat planing hull, rated for up to 85 hp. These are factory specs. I tried an 18 hp Evinrude tiller and it wouldn't plane. There are a few '59 Larks around but are only 35 hp. I'm guessing around 50 to 60 hp would be about right, but that means a later model to stay with a 2 cylinder, and I'd like to avoid the extra weight of a 4. Local outboard wizard has a 60's Johnson 80 hp 4 to sell complete with controls for 400.00 installed. He says the weight is the same for these from 60 to 80 hp. He also says it may be too big for the boat to handle structurally, although he hasn't seen the boat, its very solid. Back in '59 they would have to use a 4 to get over 40 hp eh? I'm not opposed to modern power but can't afford new. What do you think?

Ehouse

Re: Outboard for '59 Whirlwind

Can't go wrong with a '73 or newer JohnnyRude 3 cylinder. Best horsepower-to-weight ratio you'll find. '78 and newer even better.

Re: Outboard for '59 Whirlwind

if i read your post correctly you say its rated for 85 hp,correct?if so you should have no problem with the older 80.i have a 17 foot cedarstrip thats 300lbs lighter than yours and is powered by a 1982 90hp evinrude.mind you im right on the very edge of capacity for sure.ive seen one similar to mine being powered by a 30 yammy 2stroke and it went ok.maybe it was rated for 80 so you could go twin 35,s back when it was made?

Re: Outboard for '59 Whirlwind

Or if you're not stuck on OMC big twins and V-4's, you could go to an inline 4 Merc 500 50hp or a Merc 650 65 hp. You need at least 70% of the hull power rating to get adequate performance, so I wouldn't go below 60 hp unless you just want to putt-putt around on the water. Mercury went from magneto to solid-state ignition in the late 60's, don't know about OMC.