Hi
The rudder bearing House show sign of corrosion.
As it made of aluminium there is no point of adding a anode. Any suggestions to stop corrosion?
The hull is coated with coppercoat but the problem started before this. There is no copper coat on bearing House.
Regards
Zolden
Hi
The rudder bearing House show sign of corrosion.
As it made of aluminium there is no point of adding a anode. Any suggestions to stop corrosion?
The hull is coated with coppercoat but the problem started before this. There is no copper coat on bearing House.
Regards
Zolden
Suspect the corrosion started before the Coppercoat application. Electrolysis between the copper in conventional antifoul and the aluminium. The recommendation from Jefa and Bavaria is to leave 10cm clear round the housing and coat that with Trilux. However Coppercoat is not a problem as the copper is not exposed so it is the corrosion you have to deal with. Suggest you clean it up, apply Hammerite all metals primer and then paint with Velox if you can get it or use Trilux which will need renewing each year if it does foul.
I faired mine with epoxy (International Watertite) after some sanding (and grinding out the pitting). Then painted it with aluminium etch primer and propeller antifouling (Velox Plus), same as the prop and saildrive. Works pretty well and not noticed any further corrosion. The surface where it is in touch with the bearing toroid is greased (but not the roller bearings themselves). This keeps water away from the metal just like the paint does. When hauling out, I freshen up the Velox after a light sanding.
You can buy a plastic bearing housing from Jefa, but the replacement is difficult as the old is glassed in over the entire outer surface of the housing and would be a real bastard to remove (probably have to cut it out in pieces), so not doing that while the old one is doing okay.
Thank you Booth.
I'll try with sanding and primer as suggested.
Just installed new jefa rollerbearings so i'll try to Keep the bearing house, info succes i'll get a plastic house from jefa.
We'll start a 5 year trip next year so boat have to be in god shape
Jefa italian dealer told me the aluminium housing is not glassed but only silicon bonded. It is sure better mount plastic housing.