Just run it brother.

 

Run it till it breaks!!

 

bad alum casting?

 

Cavitation probably...run it but keep a spare with ya.

 

Looks like a manufacturing defect to me... I would take it somewhere and ask if there is a product or somethin you can put on it to maybe stop or at least slow it down.

 

That is from true cavitation... actually inertial cavitation in your case. A low pressure area is being formed which creates a space in the water. As the vacuum space returns to normal pressure, the space collapses and a shock wave is created which is damaging to the metal. This is where your pitting is coming from.

Something is creating this, I once had this happen half way up the blades on my ski boat prop. The culprit was a slightly bent skeg. I straightened the skeg and the 'pitting' went away. Before I straightened it, I could spray paint the prop and run it one time and the paint would be gone in the pitted area. After straightening the skeg, the paint stayed on.

You have something that is creating the vacuum around your prop. Either a deformity on your outboards foot or on the prop. If it is only on one blade, something is wrong with that blade on your prop. If it is on all 3, the problem is on your foot or gear housing.

:tu:

 

Ok that is either true or the best line of chit that I have ever heard. Id prally say that he knows what he is talkin bout.

 

He does...Way better than me..I knew it was cavitation but there was no way I coulda explained it as well as him and identified the specific type of cavitation.
Cavitation often eats up pump impellars when a pump is pumping something with entrained air or if it doesn't have enough head pressure.

 

thanks for the info. ill see if i can figue out whats causing the problem

 

quit running shallow lol

 

Is your tunnel vented? That could be the source of your vaccum...

 

no i dont im going to put a jack plate on first and see that helps if it dont im going to look in to venting the tunnel. i wish i would have stayed away from a tunnel hull

 

Yea I dont understand why the cookie cutter factories dont install a vent from the get go. All of your custom builders know to vent the tunnel...

They have their place, but they are not all they are cracked up to be either...

 

Yea I dont understand why the cookie cutter factories dont install a vent from the get go. All of your custom builders know to vent the tunnel...

They have their place, but they are not all they are cracked up to be either...

your rite when u said cookie cutter thats all weldbuilt is never agin for me. the next time ill go custom built. i believe i would have saved moneny in the long run.but u live and learn

 

never seen anything like that... id try a new prop before anything else

 

i would but im having more issue then this with the boat. it pourposing bad , its slow. its not bitting when i take off it like it spenning out. i dont know. but ill get worked out i hope

 

Definatly sounds like you need a vent installed. There was someone having the same trouble not too long ago.

 

The tunnel hull traps the air under the boat then directs it directly to the prop. air entrapped in the water is almost as bad as sand in the water. The best way to correct this is with a jackplate and run the motor as deep as you can at higher speeds then shallower when your at low speeds or shooting when your not forceing air under the hull. :co:

 

:wl: What size motor are you running and what shaft length?

 

I had all the issues you said above Ben. When I vented mine it fixed them all. I still love my boat and it was my fault I got a tunnel. I didnt want a low transom with deep sides.

 

i like the idea of a tunnel and i think ill be happy with when i get everthing work out.