Anodes and engines
Reader comments on PBO July 2018Õs Ask the Experts
Before keeping an existing saildrive leg and buying an adaptor plate to match up to a new engine, just check out the price and availability of a set of clutch plates, one for reverse, one for forward, which will be several hundred pounds. Likewise for a prop shaft which may well have worn where the seals rub. On our MS120 leg, which I stripped, prop shafts were £450 +VAT. I also found corrosion on the adaptor plate between the leg and gearbox which I was able to grit blast, fill and epoxy. A new plate was – wait for it – £850 +VAT.
It may be more cost-effective to buy a whole new unit.
For folding prop protection, anodes do indeed last only about six months. The outer hub and blades are electrically insulated from the core of the hub.
We have found that treating the outer parts with Seajet’s Pellerclean dramatically increases anode life but the instructions must be followed exactly, especially the prepping.
Simon Westmacott Kent
The subject of prop anodes is close to my own heart having suffered similar problems to your correspondent for the last 15 years. My anodes would last from three to nine months depending on who was next to me in the marina and whether they were plugged into the mains electrics.
My local Volvo Penta dealer advised painting the prop and in 2014 I came across Velox Plus, made by Marlin SA, which consisted of a green self-etching primer and a white antifoul top coat. It took several attempts to get it to stay on for a whole season (preparation was key) but it has resulted in a marked reduction in anode erosion in that after a full 12 months about 70% of the anode remains.
In addition it works pretty well in its primary function at keeping the prop clean. There is no detectable reduction in performance of the prop due to painting it.
So I can now sleep at night not having to worry that my prop is about to disappear.
Andrew Spruell Hampshire
Ring anodes on a folding prop will deteriorate fairly quickly if they are doing their job