Prop shaft anode great fixing tip

[SolentVenture]

I take no credit for this piece of advice as it was given to me by an experienced cruiser some years ago. I pass it on as it is so good.
Now you know that prop shaft adodes 'rot' from the inside out so that means that the adode that you once clamped tightly around the shaft becomes loose over time as the internal diameter increases.
A loose anode has a tendancy to run up and down the shaft and can cause all sorts of mayhem to the mountings at each end plus some very worrying nosies.
A simple solution is to clamp hose clips on to your shaft either side of your new anode then as the anode 'rots' it is contained in position and can't go 'walkies' up and down the shaft. Make sure that the hose clips are best quality marine stainless!

 

[capnsensible]

Top tip. Its worth making sure the securing scews of the hose clamp are opposite each other so the shaft remains in balance. You can also use this on the inside between the gearbox and shaft seal to prevent the shaft dissapearing if the gearbox clamps come undone. I part owned a yacht once where this happened, wasn't onboard myself but got an interesting call from the coastguard!! Always do it now.

 

[demonboy]

Great tip!

Got any tips for my now-missing end prop anode? We have a folding prop and the anode is very difficult to find. I purchased three from the boat show (for a ridiculous amount of money) and the first one came off after the first day of motoring for a few hours! Absolutely crap design.

 

[sailinglegend420]

The anode and screws on my Bruntons were missing. This time I have put silicone sealant in to help keep them in place.

Bruntons say you can use loctite - but you will probably have to drill and tap out the old plastic. They also said that they only supply prop anodes because people asked for them. A shaft anode (if it stays in place) will protect the prop OK.

 

[nimrod1230]

I,ve not had problems with the fixing screws on an Autoprop but the anode would never last more than 3-4 months. Brunton suggested I paint round the thin section surrounding the screw head and last liftout, after 1 year afloat, the anode and screws were all in place though needing replacement. This year I have painted with antifouling so will be interesting if it has the same effect.

 

[Marsupial]

Use nylon bolts

 

[samwise]

Never had a problem with rattly anodes. Probably because I replace them before they get really wasted and less effective. I always put a dab of Loctite on the threads to make sure they don't shift. However, with the price of zinc the way it is, I may be attempting to squeeze a bit more service out of the current anode set up!

 

[SolentVenture]

We have a Brunton Autoprop on our Moody 471 and after drowning the shaft end anode from April 2006 to June 2007 found it still alive and reasonably well on lifting out in early June. Admittedly the boat has only done 1700 miles in the period having sailed from Hamble to Portimao in the Algarve over last summer and then sat in Portimao marina for the winter.

The plastic screws were reasonably easy to remove although still secure thanks to some well trained crustaceans which had linked arms around them.
As for the shaft anode and my 'top tip' (thanks for the plaudits) ours was well rotted having been fitted new at the same time as the prop anode mentioned above. In fact it was little more than a shell of zinc held together by the steel fixing bands.
Fortunately the hose clips had prevented it from 'mating' with the cutlass bearing.
I was surprised at the differential amount of 'wear' between the two anodes. I would certainly not leave them unchecked for more than 12 months and on present experience would need to renew them both annually.

 

[charles_reed]

Brunton anodes

In fact the shaft anode doesn't fully protect the boss anode - but you'll find you need three shaft anodes for each boss anode.

The time they last depends entirely on where the boat is moored and the prevalence of stray galvanic currents.

The most I've had out of the shaft anode is 15 months - the boss anode lasted 3 years.
The least was about 11 weeks.

I've found that putting a lick of antifoul round the holes is the most effective way of preventing premature loss.

My shaft anode is tight for space - about 16mm only between prop and cutlass - which probably has a bearing on longevity.