more power to ya

[robert]

The mac 25 I am about to buy will come with a 5 horse Force. A friend of mine has a shiny new Johnson 15 short shaft for sale. Some say I would be buying more noise not speed. Is that true?

 

[Dave Schiller]

more power

I initially had an old 5HP Mercury engine on my Mac 25 when I got it. That worked "OK" except in waves when the rising stern would lift the short shaft out of the water with an expectedly loud noise. There were also times when the 5 would hardly push the boat into wave/wind combinations. So I needed more power.I ended up buying a 10 HP Nissan LONG SHAFT that I've used for the last two seasons. It has been great and I have yet to have the prop lift out like the short shaft did. It is also enough power to move it along just fine in all conditions.A 15hp strikes me as perhaps a bit heavy as well as probably not that much better than a 10hp. You might also lose range due to higher gas consumption but I don't really know. However, if you want to charge your battery on a longer cruise, I am not sure but I think you have to go with a 15. I could not find a 10hp with a built in charging connection. Hope this is of some help.Dave

 

[Hank Bartosik]

Short shaft a problem

As long as where you sail there is no rule regarding the use of 2 stroke, stay with something under 10 hp. Above that there are some areas that have special fees for higher hP OB.Are currents a problem?I purchased a 9.9 Johnson 4 stoke becasue I have tidal currents, and also wake problems where I launch in the Hudson River. It has shown to me that the extra thrust is quite a benefit this summer- also I had to race against an approaching thunderstorm while miles away from our dock while out on Lake George this past summer and was I ever pleased at the power. I sail the 26CHank

 

[Mike]

Too Much is not enough

Being a displacement hull,Mac25s do not respond to added horsepower the way powerboats do. You soon reach a "ceiling" which requires a massive increase in power to break through. At about 10 hp you have as much power as you can use, provided you have matched the motor with the correct prop. The prop on most short shaft 15hp motors have a pitch to provide a speed that would be suitable for a power boat. Useing that prop is like trying to drive a car in too high a gear. the result is sluggish performance, poor economy and possable prop cavitation.Add to that the extra weight and trim problems and you start to create other problems. A 10hp is about top end and if you can find a used Honda 10hp long shaft, it also has a charging coil to charge your battery under power. Remember that a Mac25 is a sailing platform and that weight, balance and economy can all affect the enjoyment of sailing.Good luck with whatever you end up with.Mike