2008 E-TEC 90 h.p. RPM's question

[Geoff]

Just commissioned my new 2008 E-TEC 90 h.p. and it runs beautifully. Starts like a light switch going on.
I know I am supposed to run it WOT at about 5200 rpm's. The boat weighs 1100lbs and I am having trouble getting RPM's over 4500 which at that reading is absolutely making the boat scream. I am not sure if the hull could handle any more speed without it getting too squirrely
Question...should I be looking to change props or can I run the engine in this RPM range and still be doing the right thing for this fine piece of hardware. I'd prefer to leave it as is, but don't want to foul up the works.

Thanks for your comments


Geoff

[SEAHORSE]

If at full throttle you are only getting 4500 rpm, you will have to get a prop 2 sizes smaller in pitch.

The motor has a 5500 rpm red-line and so anywhere between 5200-5500 rpm is fine with a normal load and WOT.

You have to have the correct rpm at WOT as that prop affects the motor all the way down the speed range.

[torew]

What is the prop pitch and speed you get? I have strange numbers on my 40 E-Tec, and suspect wrong readings on the tacho. Could of course be the same on your boat.

[Geoff]

Yes, sorry about the double post. Lost track of the first and thought it didn't hit.

I will try to get the pitch from my dealer who installed it.

In any event, irrespective of my engine...is it likely to damage a 90 h.p. E-TEC if it were to be run at 3800 - 4400 rpm's most of the time.

Thanks for your comments.


Geoff

[torew]

Post the speed along with the prop data. GPS-speed, preferably.