10 HP Four-Stroke Fuel Consumption

20hp Yamaha 4stroke

Don't think you want a high thrust at those speeds.

Have you thought about a 20hp Yamaha 4 stroke... It does not weigh much more than the 10hp.

We put one on a 24 foot powertri we designed and built... Boat does 23 knots wot. I really love that little motor. One thing to note is that at wot it is burning 2.5 to 2.8 gph which is above what the manufacture states...but burns .1 gph per hp at 1/2 to 3/4 throttle.

I wish they made outboards in this size with electronic fuel injection.

 

Hi Lord!
I have a 6.5hp engine the spec tells me that it will consume 396gram of petrol/hour/Kw this tells me i will consume about 1.5 litres at full throttle. though not an marine engine but I will use this anyway.

 

Picture!

A picture regarding the engine spec.

 

Turn Point may have a point re 15knts vs hi thrust outboard. I think the hi thrust will get you to 15 knts but you may find yourself at WOT.

I have used small outboards on many many sailboats, and there is a Major difference betweeen a "regular" OB and a Hi Thrust. This difference is most apparant when going into gear from a standstill. With the regular OB you put the critter in gear, give it gas, go to the cooler and get a drink, look around to see the way is clear, and about then you notice the boat is beginning to move. With the Hi Thrust motors it is advised you be holding on to something when you put it in gear as you will start moving immediately.

This is of course a bit exagerated, but not by much.

And a last comment about the Yamaha 9.9 hi thrust 4 cycles. I used to grind the heck out of the starter gears until I finally learned to check the pee holes before turning the key. At idle from 10ft? away I usually couldn't tell if they were running by listening for them.

Steve

 

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Thanks, you're sure right about the weight:
9.9 high thrust http://www.boats.net/outboard_motor/Yamaha/9.9HP/parts.html
20hp http://www.boats.net/outboard_motor/Yamaha/20HP/parts.html


And the cost isn't too much different....