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Discussion Starter #1
Hello,
My driveshaft has turned green. I have owned my 30 year old boat for 4 years. This past year it has turned green. The stuffing box has also started leaking about 1 drop every 12 seconds, and I think that is the problem. There is also what looks like a mineral build up where the shaft goes into the stuffing box. I just want to make sure it isn't electrolysis. My diver says I have about 60% of my zinks left.
After I repack the stuffing box, should I worry about removing the
green. I don't want the bolts to seize up. How would I remove the green? I could brush the shaft, but I don't know if the geen build up is in the threads.

I tried to include a photo, but when I click the "insert image tab", I haven't been succesful. Can someone please tell me how to do that?

Thanks - Larry
 

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Larus Marinus
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1,756 Posts
Green sounds like copper oxide deposited by electrolytic action. The copper probably comes from the bronze or brass in your stuffing box. I guess that means 1) your stuffing box is leaking and 2) there is a bronze to SS shaft contact, forming a nice little battery.

I suggest re-packing your stuffing box.
 

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Aquaholic
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You also did not specify what material your shaft is constructed of. Is it Bronze or Stainless? Most that I have encountered of that vintage have been Bronze.

As to photos, do a search, there is a GREAT primer on how to post photos using a hosting service.
 

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Telstar 28
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Justonemoreproject-

If you want to post a photo, go read the photo posting instructions in the General Discussion forum.
 

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Discussion Starter #5
Photo attached

Hi,

Thanks for the directions on how to photo post. I am concerned about working on the stuffing box while the boat is in the water, since I have never re-packed one before. It may, of course it will, take a while to figure it out while water is coming into the boat. Ab

At what flow rate could I anticipate water entering the boat during this procedure? Would it help stop the galvanic action if I put a Zink temporaily on the shaft on the inside of the boat until I can haul?

Thanks for your support.
 

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Zinc's won't be much help with oxidation. What you can do until you can haul the boat is to spray everything you can get to with a good corrision spray. The best I've seen is Corrision Block (it's made by Lear). You can get it at most marine stores.
 

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Larus Marinus
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I would not risk unpacking the stuffing box with the boat in the water. Depends on the type of course, but even so, the bit you are replacing is stopping the water getting in.
 

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Juston :

Don't re-pack it when it is in the water!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

The moment you pull out the old packing, you will be caught in a blast of freezing water that will make work impossible. You won't be able to see anything with water blasting everywhere.
You will not be able to get the new packing in there either as the pressure difference across it will keep blowing it out again. You will have to haul then or your ship will sink..... that's if your ship's pumps can keep ahead of the water entry rate until you can haul.

Don't even think about it.

You must haul for this procedure or at least try to do it between tides!!!!!

Don't do it Juston. Don't do it man.
 

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I've not redone a packing box while in the water - nor needed too - but I would think if you wrapped the thruhull with very light plastic sheeting (multiple layers) from the outside and used perhaps a hose clamp around the shaft over the plastic that the influx of water created by removing the packing would suck the plastic into place blocking the flow enough to restuff the box. ? I'd give it a try before paying $300 - $600 plus lay time to haul it. But I would do it in very... shallow water.
 

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Wish I never found SN!
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I saw this done in Fiji, Suva harbour, use modeling clay to seal the outer shaft, simple.
 

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Well, maybe, but you need a formal defence against the water getting in there. My own stern bearing assembly would not perrmit the plastic bag trick really. It's a full keel.

What about between tides?
 

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Larus Marinus
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I think it depends on the stuffing box type as to whether a diver with modelling clay would work or not. On some types the shaft has to be detached and moved aft a little to slip a new sealing ring over it. That would defeat the modelling clay method, unless the diver was down stuffing it back in while the shaft moves aft. Plus he could stop the shaft sliding right out under its own weight from some boats.

Since most boats have to come out fairly regularly for antifouling and anode replacement and a few other checks, the shaft seal can be done as well. As Rockter says, in tidal areas, drying out is often used for such tasks.
 
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