At 05:17 PM 8/19/2010, tmc664 at comcast.net wrote:
>Hi all
>I did a lot of reserch before buying my engine and here's what I
>found. Tohatsu builds all the 4 stroke Tohatsu, Nissan and Mercury
>engines below 40 hp. The 4-5-6 hp engines all weigh the same, 55 lbs
>for short shaft and 57 lbs for long shaft. The 4-6 hp engines all
>use the same parts, the difference being in carburator jetting and rated rpm.
>>I bought the 6hp version as there was no weight penalty for doing
>so. It was a bit more expensive. One thing I found out is that the
>market for these engines are little inflatables that weigh less than
>1000 lbs and buzz around at 15 -20 mph. The props on the 4-6
>engines are pitched accordingly. Hang it on a 2600lb + sailboat and
>it wont make full power unless going to a finer pitched prop.
>Basicly HP is a function of MP(manifold pressure) and RPM. 57lbs is
>a PIA to get on and off the tail end of a Tuna.
>>I've had both a strong 4hp and new 6hp engine on my Santana here in
>the Bay Area and preferre the safety margine of the 6 hp version.
>>Your mileage may vary.
>>Tom McIntyre
>>Spitfire # 802
>_______________________________________________
When we bought a new a 5hp 2-stroke Johnson for Dominatrix (#419) in
y2k, I also had to buy a "flatter" prop to get acceptable performance.
If going to a more powerful motor gets you an external gas tank
connection (and no extra weight), that alone might be worth the price.
-Ted Crum
