Seacock maintenance

Technical information and geeky boat stuff
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BALANCE
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Seacock maintenance

Post by BALANCE »

Is anyone aware of an already made primer for servicing the old bronze Groco seacocks. The levers on some are mighty stiff. (these are the kind with the rubber cones that are no irreplacable).
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Rachel
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Post by Rachel »

I don't remember what we used to service those rubber-coned Grocos. The cones are pretty impossible to get in the popular sizes though, you're right!

Here is a nice guide for servicing "old-fashioned," cone-style bronze seacocks. This is for Wilcox-Crittendens, which have a bronze cone, but you might find it useful anyway.

http://www.pearson35.com/projects/sea_cock.htm

I love how they called them "Seacox." Wilcox/Seacox... get it? Hee.

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BALANCE
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Post by BALANCE »

I get it, tee hee.

I'm not going to yank them out of the hull, I just want to lube it from inside. Just not sure how to disassemble. The same lube (which is used for trailor hitched) is rubbed around the cone. There is some discussion of this on THE board but not enough detail for my pea brain...

Here is the one in the engine room..

Image
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Rachel
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Post by Rachel »

I understand: You're not taking them out of the boat. I'm just not sure how you can lubricate them without doing that (?)

Here is another info sheet. Again, geared towards the boat being out of the water, but I still think it might be helpful for you to look at. These are Spartan seacocks which are similar to yours but with bronze cones instead of rubber.

http://spartanmarine.com/source/27.htm

Also, do you have Nigel Calder's "Boatowner's Mechanical and Electrical Manual"? I may not agree 100% with him on everything, but I still wouldn't own a boat without his book on hand. Tons of good information and very clear drawings. Your exact Groco rubber-plug seacocks are shown in an exploded diagram on page 566 of the third edition.

Re-familiarizing myself with it now, I don't see any way to "lube the handle" without taking the seacock apart. That's because what the handle does is turn the plug, so stiffness would be caused by the plug being swollen or needing grease. That's the part you have to maintain by removing the plug (and unless you're bold/confident, having the boat out of the water.) That is, there are ways to do it with the boat in the water (plug the through hull from the outside, etc.; but going by what you're saying, I don't see you wanting to do that this time around.

Is it possible the rubber plugs are over-tightened? This can make the handle hard to turn. You could loosen the handle that "balloons" the plug as long as you don't make it start to drip.

One note, from the book, is that "these seacocks are not suitable for applications where chemicals may be present (e.g. toilets and sinks). The rubber will swell, jamming the bung and making it next to impossible to turn [the handle]. You can salvage a bung that has swelled by filing down the excess rubber with a coarse wood file or a belt sander."

So perhaps your rubber plugs have swollen from some contact with chemicals.

By the way, "trailer hitch grease" is probably white lithium grease. I'm not sure if that's what we used - just can't remember. I see that Spartan has their own proprietary grease. I feel like I read some discussion of what the various people use on the Spartan seacocks on the Cape Dory board last year (I had a bunch of Spartan seacocks that I was thinking of using on my boat, so I was reading about them). I think people used something like "red dot" grease, but just can't remember the details. (Not saying white lithium is incorrect - but just be sure whatever it is won't hurt the rubber cones.)

Rachel
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Post by Quetzalsailor »

Be sure to use the grease/lubricant sold for use on that type of seacock. Not every synthetic rubber will tolerate hydrocarbons; I suspect that most would not.

I think that Rachel is right in saying that this is a job for when the boat's out of water. You have to get the plug out to clean and lubricate both the plug and the casting in which it rotates. If you 'fothered' the bottom at the seacock you might succeed in dissassembling, cleaning, lubricating and reassembling while in the water but the excitement would be too much for me!
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