Fitting a new prop.

[greeny]

Hi all,
I'm just about to replace my standard 3 blade prop with a folding 2 blade. The new prop has not got the facility for an anode like the old one had. The shaft has no space to fit a shaft type anode so I intend to fit a hull anode near to the prop and bond it to the engine. Is this enough to get good conductivity and to protect the prop or do I need to fit a shaft pick up earthing system as well? I only have a standard shaft coupling and the engine is a 3ym20 yanmar. Any thoughts on the subject?
Greeny

 

[Tranona]

You may not need to fit an anode. Usually if the prop material is prone to dezincification the maker will fit an anode. Ask the manufacturer. My Flexofold for example does not have an anode. If the advice is to it one then bonding a hull anode to the gearbox casing normally works if you have a solid coupling.

 

[theoldsalt]

If the shaft is isolated from the engine by a synthetic flexible coupling it is usual to bond across the shaft and gearbox flanges. So no need for prop or shaft anode as the engine/gearbox should already be bonded to a hull anode.


View attachment 40325

 

[greeny]

You may not need to fit an anode. Usually if the prop material is prone to dezincification the maker will fit an anode. Ask the manufacturer. My Flexofold for example does not have an anode. If the advice is to it one then bonding a hull anode to the gearbox casing normally works if you have a solid coupling.

Thanks Tranona, it'll be a bit less work to do if I don't have to. It's a flexofold that I'm fitting so I'll check the website but it sounds like I'll be OK without doing anything maybe.
Cheers

 

[Tranona]

Thanks Tranona, it'll be a bit less work to do if I don't have to. It's a flexofold that I'm fitting so I'll check the website but it sounds like I'll be OK without doing anything maybe.
Cheers

The 2 blade comes with or without an anode. Suggest you call Darglow Engineering who are the UK distributors for advice on your set up.

 

[alahol2]

I have a Flexofold without an anode. I also have a hull anode bonded to the engine. Checking the continuity between anode and prop shows a low resistance. The anode isn't really very close to the prop, 2 or 3 feet so I'm not sure if it is protecting it or not.