Maxi prop anode failure

[Chris CJ]

I’ve had two successive failures of 70mm maxi prop anodes on our Najad 400 , supplied by Force 4 , the reason these have prematurely failed is due to the non existence of the metal ring embedded with the zinc casing . I have taken this up with Force 4 , “they will take it up with their supplier “
have I been unfortunate with two duff anodes or this there a greater number of premature failures due to the missing metal ring.
I have since bought replacement anodes from technoseal , but have no idea if these contain an embedded metal ring , other than cutting into with a hacksaw , if something hard is encountered the probability this the metal ring exists - a bit drastic . I have made an enquiry to Technoseal this morning.
any thoughts , comments , suggestion or failure experiences
chris

 

[PaulR]

one of ours wasted away around the bolts quickly and came off - for the replacement we were advised to use nail varnish or similar around the bolt holes when fitting and that seems to make a huge difference - now the conical part of the anode wastes away before the areas around the bolt holes - no idea if the anode has a metal ring embedded in it

 

[wilkinsonsails]

I’ve been using a little of the prop antifoul just around the bolt holes .This means we get 2 seasons out of the anode ,which wears evenly and doesnt fall off .

 

[Chris CJ]

Some better news , MG Duff have confirmed there zinc maxi prop anodes do have a metal ring embedded when casting.
unfortunately they are twice the price of the ones on offer from Force 4 and others . Buy it cheap ,but twice or in my case thrice comes to mind.

the cost of the anode is nothing compared to a boat lift and the protection it affords

hopefully this will be helpful if you are considering maxi prop anode replacement

Chris

 

[penfold]

The anodes on Brunton Autoprops don't seem to have a steel armature in them; daubing nail varnish around the fastener holes to prevent local erosion seems to work well enough to secure them for the season.

 

[Goldie]

There is/was an adapter kit available from Darglow engineering which allowed the fitting of a much ‘meatier’ anode to a Maxprop. We fitted one and get much longer life from the bigger anode and it’s also easier to change under water.

 

[ithet]

Most of the anodes for the Maxprop are like that. I paint (with antifoul usually) around the fixing screws all the way to the edge of the hub. This seems to hold back the erosion around the fastenings enough to keep the anode on for a season. It is also necessary to use locking fluid on the screw threads.

This is what the anode thus treated looks like after a season:

 

[Chris CJ]

Technoseal have confirmed they don’t embed a steel ring in there maxi prop anodes .
interesting use of nail varnish and anti foul around the bolt holes - clearly a good solution to preserve the anode around the fixing points to maximise the life of the anode - thank you for this tip
Chris

 

[alexincornwall]

Unfortunately Darglow no longer manufacture the adapter plate that would enable a centrally fixed anode to be fitted. I enquired about that in February and they advised they'd stopped producing them, why I do not know. The prop anode is definitely the weak link on our anti galvanic armory, and we suffer the same problem as everybody else.

 

[Graham376]

Technoseal have confirmed they don’t embed a steel ring in there maxi prop anodes .
interesting use of nail varnish and anti foul around the bolt holes - clearly a good solution to preserve the anode around the fixing points to maximise the life of the anode - thank you for this tip
Chris

Antifoul around the bolt holes works for me on Feathersteam anode.

 

[Chris CJ]

After a lot of asking of various supplies , MG Duff are the only supplier of maxi prop anodes that contain an embedded metal ring within the zinc casting that I could find in the Uk , almost twice the price of one without . The best on offer with free delivery was to buy three from ASAP Supplies , Just need to find some replacement hex bolts , I think they are M4 20mm in grade A4 stainless steel , would be grateful if anyone can confirm this .

 

[roaringgirl]

I think they are M4 20mm in grade A4 stainless steel , would be grateful if anyone can confirm this .

Our maxprop anode is fixed with plastic screws. It has lasted 2 years and all the way from Edinburgh to Bonaire. I checked it before we splashed a month ago and decided it doesn't need replacing yet.

Almost all the corrosion happened in the few weeks before we departed Edinburgh - where we were connected to shore power the whole time. Since then we have only plugged in very occasionally. I do not think the longevity of our anode is a coincidence.

 

[Kukri]

Our maxprop anode is fixed with plastic screws. It has lasted 2 years and all the way from Edinburgh to Bonaire. I checked it before we splashed a month ago and decided it doesn't need replacing yet.

Almost all the corrosion happened in the few weeks before we departed Edinburgh - where we were connected to shore power the whole time. Since then we have only plugged in very occasionally. I do not think the longevity of our anode is a coincidence.

I think you are right! Same sort of experience. This one just made it…