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Old 14 June 2009, 22:49   #11
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Getting back on thread - Is this an example of cavitation erosion about 10mm in from the leading edge of all three blades on this prop. Both props were like this and looking decidedly flimsy on the leading edge. I was planning to replace the pair beforeI struck some concrete in an indicated 13 foot of water 150m off the beach. I have since been able to source one replacement and awaiting another. The second prop has this sort of pitting damage but the blades are okay - is it possible to have the better of teh two props rebuilt as a spare?

I also wondered whether this damage as linked to anodes being ineffective or the effect of missing earthing straps between leg and engine mounting bracket?

Any advice gratefully received
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Old 15 June 2009, 03:55   #12
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I ran a too-small (pitch) prop for a bit with a missing spacer. Ended up with a line cut about a half-inch in from the tips, starting about a half inch from the leading edge, and about an inch and a half long. It ate through the plastic (epoxy?) paint, and into the aluminum. ended up removing perhaps .040" depth, about 1/4" wide.

If it's eating metal over most of the blade width, I'd suspect electrolysis. if that's the case, the surface should have a definite pitted appearance.

jky
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Old 15 June 2009, 04:33   #13
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Originally Posted by Andy Young2 View Post
I also wondered whether this damage as linked to anodes being ineffective or the effect of missing earthing straps between leg and engine mounting bracket?

Any advice gratefully received
Paint damage on hub looks more like electrolitic corosion,
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Old 15 June 2009, 05:13   #14
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I believe that this can also be caused by having a prop thats diameter is too small.
This was certainly the case with me,while sorting out the right prop for the new e-tec tried a few different sizes,finaly settled on 19''[engine supplied with 17]sorted!...ALSO!
CONGRATS TO CHRIS AND FAMILY!!! BONNY NEW BABY BOY 'CHARLIE' ARRIVED AT THE WEEKEND, All the best from Karen and me!....
See the trouble being a 'Born fiddler' can get you into!
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Old 15 June 2009, 05:54   #15
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