Metal erosion
 

I have a 43 Black Thunder with labbed 24 Bravo 1's. They had a nice polished finish but slowly the starboard one seems to be eroding. It's on the leading edge of the blade about halfway across. The port prop is still nicely polished. What causes this and do I have to worry about the prop coming appart?

Re: Metal erosion
 

prop burn? passing air bubbles over prop surface.happens over 50 mph?..........m.m..........

Re: Metal erosion
 

Yo're over 50 a lot Mark, is that something that's common?

Re: Metal erosion
 

but i dont have prop burn!!!!!!!!!!!m.m.......

Re: Metal erosion
 

Cavitation burn can be caused by a variety of reasons.

What it actually is though is a pressure differential on the high pressure side of the blade causing the water to boil. The turbulence is violent and burns the metal away.

24 Bravo1's aren't known to have a geometry to induce this. Your situation would be caused by drive height, hull configuration, transducers, etc. causing aerated water to attack the face of the blade.

It is possible to have a casting with extensive porosity which may accelerate the process.

Re: Metal erosion
 

would the boiling create air bubbles?...m.m...

Re: Metal erosion
 

The pressure change cause the boiling which is the bubbles.

Re: Metal erosion
 

thank you............mark...........

Re: Metal erosion
 

If you could post a picture, we could possibly determine whether you are experiencing cavitation burns and not an environmental issue such as oxidation or electrolysis.

Julie

Re: Metal erosion
 

Thanks for the replies. I'll try to post a pic tonight.