Stainless steel props and longevity of anodes

dave1dpc

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Since changing to s/s last season I have experienced a far greater depletion of anodes. This is even with a galvanic isolator in series with the supply and another large bar anode on the transom twixt the outdrives. This leads me to ask the question. Would painting the ss props or powder coating reduce the conductivity ? Not seen it done before so there must be a good reason..... Q Volvopaul or Spannerman?
 
I doubt they would be truly isolated and certainly not for long as all props shows signs of wear and tear eventually which would erode the coating. Its not unusual to have increased anode erosion with SS props as they conduct better than aluminium. However if you are running D4/6’s which has the DPH drive then these props are electrically isolated from the prop shaft. Also are you sure there isn’t a boat near you that has a electrical problem as your SS props are now a very good anode. My mate had a Princess V 45 and one day completely lost his steering, when we got the boat on land the aluminium steering cylinders had been completely eroded around the end caps and one had blown out dumping all the hydraulic fluid, we fixed the boat and he had his berth tested and found the boat in front was pumping a lot of stray current into the water as it was a bad shore power installation. The current heads to the nearest ground which was a pile under the quay and his drives were in a direct line so got attackedby the stray current.
 
He had his berth tested and found the boat in front was pumping a lot of stray current into the water as it was a bad shore power installation. The current heads to the nearest ground which was a pile under the quay and his drives were in a direct line so got attacked by the stray current.

Yep, we had one customer who went to S/S props. Within a season all the anodes were pretty much gone and the props had signs of pitting. The boat next to him was spilling current all around and other owners found that they too had problems.
 
I was going to say - most people I know have ss props and have them painted....using Velox plus this year - last trilux,.,..agree - less growth = better performance and sounds like better retention of anodes!
 
I doubt they would be truly isolated and certainly not for long as all props shows signs of wear and tear eventually which would erode the coating. Its not unusual to have increased anode erosion with SS props as they conduct better than aluminium. However if you are running D4/6’s which has the DPH drive then these props are electrically isolated from the prop shaft. Also are you sure there isn’t a boat near you that has a electrical problem as your SS props are now a very good anode. My mate had a Princess V 45 and one day completely lost his steering, when we got the boat on land the aluminium steering cylinders had been completely eroded around the end caps and one had blown out dumping all the hydraulic fluid, we fixed the boat and he had his berth tested and found the boat in front was pumping a lot of stray current into the water as it was a bad shore power installation. The current heads to the nearest ground which was a pile under the quay and his drives were in a direct line so got attackedby the stray current.
Im on twin Bravo 2. The reason I fitted a galvanic isolator I thought to prevent stray current from nearby boats etc. The wear on s/s props is more than double ally. I even added an additional large anode on the transom. I thought that powder coating would help to reduce the conductive surface.
 
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