3288 bayliner with rudder pitting issue-gctid824014

[Bludool1]

I have been all over the boat trying to find out what stray current I might have. I can not locate. I am having an issue with the rudder developing pits.

Bonded, has zincs on rudder. See picture. The ground spots are from me cleaning it up when out of water.

Any advise would be much appreciated.

Can't add pic. Not sure why.

[Bludool1]

trying to add picture

[Norton_Rider]

Have you tried this?

http://www.powerandmotoryacht.com/systems/how-check-your-boats-bonding-system/stray_current_test

[yachtman]

I don't know where you are located but I have 2 good used rudders for sale $1500 for both or $800 for 1

[yoeman]

Sand them to see how bronze they are after the pitting is gone

If they are pink that's not good.

I've had a few boats with this issue

[Guest]

"Bludool1" post=824014 wrote:
I have been all over the boat trying to find out what stray current I might have. I can not locate. I am having an issue with the rudder developing pits.

Bonded, has zincs on rudder. See picture. The ground spots are from me cleaning it up when out of water.

That is strange with your rudder equipped with zinc's. This assumes you're using the right anode material for your water type- fresh, salt, etc. and no one has accidentally intermixed anode metal types, i.e. aluminum anodes with zinc anodes, which can compromise protection as I understand it.

I suggest buying the following:

1. The reference electrode which allows testing in the water of your bonding system. Yeah, it's $125, but how much does ANY damage add up to $$?

http://www.boatzincs.com/corrosion-reference-electrode.html

2. Nigel Caulder's book 'Boatowner's Mechanical and Electrical Manual' which gives a detailed procedure on testing, along with a tremendous amount of information on other subjects. Looks like they have used copies cheap.

https://www.amazon.com/Boatowners-Mechanical-Electrical-Manual-Essential/dp/0071432388

Be methodical in your approach and document readings as you go. My two cents, Dean

[Pcpete]

Plus one on Nigel's book. I bought it for electrical ground fault investigation but I've found it's a whole lot more.

[boatworkfl]

Make sure you have a b0nding strap on the rudder shaft inside, also you should have a shaft wipe for bonding the 2 shafts, all connected together with 8 ga green jacketed wire connected to the engine block.

Everything with zincs should be bonded together including the transom zinc. Then check the bonding system with a meter as suggested.

I just returned to Florida from Alaska, I may have a spare silver/silver chloride half cell in like new condition, it is my spare, it has a long cable.

Give me a day or 2 to find it, I am hoping I brought it back, it will cost much less than the $150.00 model suggested.

Still looking for the half cell.

I use a pro Mariner analog meter and half cell, $288 street price, $255 at Fisheries supply with a commercial account, includes half cell and meter.

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwid07_TrK_WAhVIMSYKHe-rBwwQFgg2MAA&url=http%3A%2F%2Fwww.fisheriessupply.com%2Fpro-mariner-analog-test-meter&usg=AFQjCNE-T7SWf7AFeg9CBS_pkx5P81J8MQ

[Bludool1]

Bought the reference electrode from Boat Zinc. May try it out this weekend. I spoke directly with Boat zinc, and they recommended taking the rudders out of the bonding, as long as I have zincs on them.

Will let everyone know how it works.

Thanks