Boat Testing for WOT

[gdean7]

I'm a little afraid to do this, but can I test the WOT for my Force125 outboad, out of the water? It says nothing about it in the manual, I have a hose hookup, but it seems like running that fast it may be bad for it. Any help is greatly appreciated, thanks! <br /><br /> Also, where do I hook up the handheld tach on the boat to get the right test for RPM,s? Thanks!

 

[Realgun]

Re: Boat Testing for WOT

The straight answer is no. The other answer is take it to a marine mechanic he will have a tank or a wheel that puts the right amount of pressure on the prop. <br /><br />You need to test the boat under load on the lake. <br />What you do is warm up the motor, trim the engine to the best angle and give it all shes got! Then, and you should know this, the WOT RPM the MFG recommends. Lets say the Max is 4500-5500rpm.<br />Your tach says 5200. You can go to a 2 inch lower pitch and get 5400 BUT if you are heavily loaded then you will over rev the motor when lightly loaded understand?<br />Lets put it this way if you are at the upper end and lightly loaded your at the correct prop. If you are heavily loaded and near the bottom your prop is correct. If you in the middle you just right. <br /><br />Only adjust or change the prop if your out spec.<br /> <br /><br />>>>>DO NOT RUN THE MOTOR AT WOT ON A HOSE.<<<<<<< <br /><br />You will most likely break the motor and damage the water pump.

 

[roscoe]

Re: Boat Testing for WOT

Same as above but with an even more emphatic NO NO NO !!!

 

[gdean7]

Re: Boat Testing for WOT

Awesome, thanks all!

 

[gdean7]

Re: Boat Testing for WOT

Quick question. The Clymers manual I have more ore less expects you to know what pitch prop is. And I assume you all do too. Sorry to ask, but just so I get an accurate WOT and tach reading, what is pitch prop?

 

[Dunaruna]

Re: Boat Testing for WOT

Take a look at this:<br /><br /> http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=36;t=000030 <br /><br />The link above will give you all the information you need, and then some .<br /><br />Good luck.<br /><br />Aldo

 

[Realgun]

Re: Boat Testing for WOT

Let me give you some help here. Diamter is the sweep of the blades. Pitcxh is the forward slant of the blades.<br /><br />So here it is. Diamter is the imaginary circle the blade reach. The pitch is the slant of the blade. If the blade is a 15 pitch then thoeretically the prop in 1(one) revolution will move forward 15 inches.<br /><br /> A fun toy .

 

[roscoe]

Re: Boat Testing for WOT

Pitch:<br /> http://www.boat-props.com/prop_info_2.cgi?page=pitch <br /><br /><br />Effect of pitch on rpm:<br /><br /><br /> http://www.boat-props.com/prop_info_2.cgi?page=rpm

 

[Realgun]

Re: Boat Testing for WOT

Roscoe did you like my toy?<br /><br />There is another toy that I forgot to book mark that is better.

 

[Realgun]

Re: Boat Testing for WOT

My Fav toy calculator.<br />That page is awsome. But remember it is more fun to be on the water WOT than sitting in front of the computer dreaming.