Stainless Props verses Bronze Props

[Guest]

I have an electrolises problem through the shaft to which I am in the meantime attempting to isolate by connecting the neg(-) through a switch to the engine block. The problem shows itself by throwing off the antifoul on the prop ( don't worry I've tried ALL the different antifouls) if I get rid of the shaft anode as this is supposed to cause the antifoul to dissappear the bronze prop takes the brunt of the problem but at the expense of the prop

SO

if I substitute a stainless prop for the bronze prop with no anode is the antifoul and electrolisis problem solved???????? if so why? if not - any suggestions?

Gordon

 

[Guest]

No, I don´t think a stainless prop would change anything. But I wonder, do you have a good electrical connection between engine and prop shaft? Many flexible couplings are in fact insulators and need to be overridden, for instance by a cable connecting the two halfes.

 

[Guest]

Symptoms - Cause

If you have sufficient current flow to make your antifouling fall off, I would suggest you have much greater problems than simple galvanic couples. The vast majority of boats have bronze propellers, stainless shafts and anodes, without any trouble. I suggest you look at your electrical system, mains and 12V, very carefully, to identify leakage to earth. See Nigel Calder's reference book for possible causes.

 

[Guest]

Thats interesting Gunnar as i have been told to isolate the shaft from the block

Gordon

 

[Guest]

Re: Symptoms - Cause

Thanks Vyv - as always "if all else fails read the instructions or consult the experts"

Gordon

 

[Guest]

No, to my knowledge there must alway be a good electrical connection between engine and prop. I agree with the other reply, there must be a considerable stray current going somewhere and referring to Calders book is a good one, if you don´t have it, buy it or steal it, whichever. This book is worth almost any effort.