Originally Posted by groundedsailor
I am a first time sailor and purchased a 1975 Mirage 24. The 6 hp Johnson was not in the best of shape when I purchased the boat but I used it a couple of times with some degree of frustration. The motor is now shot and I'm in the market for a now one. I have several questions.
1 does any one now the maximum hp for a mirage 24
2 how long of a shaft do I need, 20 or 25"?
3 Yamaha dealer close by suggested 8hp with turbo, would that be too much?
4 with motors in short supply at this time the choices are Yamaha 6 4strope, Honda 5hp 4 stroke or Mercury 6 hp 4stroke. Any preferences, things that would be helpful to know.
Any assisstance would be helpfull.
Ok - I'll give this one a shot.... I owned a 26 footer for ten years with two different 10 hp four strokes on it over time, and before that 20 footer with a Johnson 6 two stroke on it, for five years. I admit to some prejudice as that late-70's Johnson was a poor motor and measured in modern terms probably put out a useable 4 hp on a good day! We later replaced it with a 4 hp Merc two stroke that had noticeably more push.
With the hinged mount shown in the one picture I could quickly find via Google, it looks like a long shaft (20" leg) might have been the original choice. As others note the 25" leg might be preferable as long as the prop does not drag much when the mount is up and motor is tilted up. One caution from my former years with smaller boats with this setup: be sure that whatever you choose will actually tilt to the "lock" position when the motor mount is raised and the motor tilts, putting the housing against the top part of the transom or rail.
Note B: if you have been getting by on a 35 year old Johnson two-stroke, you will be astounded at the power in a modern smaller four stroke outboard.
Displ. is given as 3750# on one for sale listing I checked. I would put no more than an 8 hp on it, and if you can score a deal on Honda 5, that might be just right. Both Honda and Yamaha have the maximum R&D and sales record in four strokes, IMHO.
Our previous sailboat had a Yam 10 Hi-Thrust and it was more than the boat needed. (Niagara 26, 4K displ)
Whatever you decide on, be sure the engine and final drive ratio (and the prop pitch) is appropriate for a displacement hull. Yamaha used to have some small (i.e. 10 hp and below) four strokes with a three-to-one final gear ratio just for this market. This is way different than the mass-market outboards with their two to one gearing that are intended for the small planning skiff fishing market. Flatter prop pitch will make up for this to a large degree, but still short of having proper gearing.
Hope this bit of trivia is helpful, and worth about two virtual cents!