Corroded prop - do i need to replace?

drude

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For various reasons all of which are my fault, I neglected to replace my prop anode at the expense of some prop degradation. See photos.

The anode has now been replaced and the prop still feels strong but have I left it too long and is there anything else I should do to immediately halt the process?

Many thanks

Lesson learned.

A
 

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Tranona

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not a Brunton. just a simple folding prop. clean it up and see how deep the pits are plus whether it rings true. Unlikely to fail but the pits on the blades may affect performance.
 

vyv_cox

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I have seen folding props like this on which the teeth at the blade bases have dezincified badly and collapsed. This of course would prevent the prop from opening correctly. The pits on the blades can be ground out a little but if the teeth have failed it is scrap.
 

drude

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That looks like a Brunton.

Drop them an email and ask them what they think. If it was me I'd be reaching deep into my beer token fund.
Thanks Sandy and everyone else. It is a flexofold and I got an immediate comprehensive reply from them. Apparently it wasn't the anode at all - not galvanic corrosion . I have a new problem to fix asap - electrolysis caused by stray current.

WIll break out the multimeter this evening!
A
 

Sandy

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Thanks Sandy and everyone else. It is a flexofold and I got an immediate comprehensive reply from them. Apparently it wasn't the anode at all - not galvanic corrosion . I have a new problem to fix asap - electrolysis caused by stray current.

WIll break out the multimeter this evening!
A
Their customer service is good.

Good luck with the multimeter, I did see that anode on the prop shaft, scratched my head and wondered why the pits were as big as our potholes when that anode looks hardly touched.

Are you in a marina?
 

drude

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Their customer service is good.

Good luck with the multimeter, I did see that anode on the prop shaft, scratched my head and wondered why the pits were as big as our potholes when that anode looks hardly touched.

Are you in a marina?
Yes and connected to shore supply. I've installed a new chart plotter and stereo in the last 18 months so will first check stray current in boat systems and then stray from dock. Although I do have one of those galvonic isolaters in place. In any event the red colouring on the prop says this is happening "now" so i'd better get my skates on and disconnect the internal batteries until problem solved. I was looking for a job this Easter!
 

Sandy

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Yes and connected to shore supply. I've installed a new chart plotter and stereo in the last 18 months so will first check stray current in boat systems and then stray from dock. Although I do have one of those galvonic isolaters in place. In any event the red colouring on the prop says this is happening "now" so i'd better get my skates on and disconnect the internal batteries until problem solved. I was looking for a job this Easter!
Ahhhhhh...

A galvanic isolator should protect you. I always unplugged the AC when I was in a marina, but I am very careful.
 

William_H

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Yes if at all possible I would not leave boat connected to marina power supply even with GI fitted. Can't imagine stereo with keep alive power on all times causing this problem. ol'will
 

thinwater

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What with solar power so inexpensive, I have not plugged in at my home marina in 15 years. Sometimes, to run AC, but I then unplug. One less thing to muck with when I head out for the day.

Yes, I have a galvanic isolator.
 

drude

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Well put! The GI i had installed clearly did nothing to prevent electrolysis. I've disconnected everything and have the professionals looking at the cause. It's going to be an insurance job for a new prop and to check the skin fittings newly installed only a year ago.

It's true though - don't trust marina power!
 
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