Lubrication thru hulls

Clydo

.
May 28, 2013
338
Catalina C310 SF Bay/Delta
Any suggestions what product to lubricate thru hulls? Friend heading out the
Gate and down South for three months. Since can't discharge in San Francisco
Bay hasn't used head in long time so direct discharge thru hull (and others) needs
lubrication.


Clyde Thorington
C310 # 245
I LEAN TOO
San Jose, CA
 
May 1, 2011
4,189
Pearson 37 Lusby MD
When my boat is hauled for dry storage, I clear the barnacles with an appropriate tool. Then, with the through hull closed, I apply waterproof bearing grease and cycle the valve. Repeat. Works best with a helper.
 
Jul 12, 2011
1,165
Leopard 40 Jupiter, Florida
You probably have Forespar Marelon seacocks, and the manufacturer’s recommended lube is Marelube (brilliant naming) ... https://www.forespar.com/marelube/

Best to lube them out of the water and disassembled to get both sides of the ball. If you only go from the outside like @kappykaplan suggested, with an qtip or syringe, it only does the half that faces outside and never the half that turns to the boat.

It’s a great non-petroleum grease, but expensive. It does work very well, and doesn’t seize up if not exercised, like some petroleum grease does. It’s also really good around the boat for any small grease application, particularly on plastic as it cannot damage. Personally, I apply a tiny amount to my main hatch slide to stop the squeak.
 

Gunni

.
Mar 16, 2010
5,937
Beneteau 411 Oceanis Annapolis
Even if you aren’t using the head, or discharging you can always “exercise” thru-hull valves to keep them in good working order. Every valve should be worked open/shut on a regular monthly basis. If they are frozen, NOW would be a good time to determine that. There are some tricks to free up valves that do not always work and replacement is required.
 
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Jan 22, 2008
8,050
Beneteau 323 Annapolis MD
... you can always “exercise” thru-hull valves to keep them in good working order. Every valve should be worked open/shut ....
Remember to exercise those valves in the house, under the sinks and all.
 
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JRT

.
Feb 14, 2017
2,037
Catalina 310 211 Lake Guntersville, AL
When lubricating the valves, is there any concern with getting residual lube into the systems these values are feeding? Maybe a dumb question but this is new territory to me. Also @JK_Boston_Catalina310 have you been using the in the water product? I figure you have to be the extreme tester for all things C310 right now.
 
Nov 18, 2010
2,441
Catalina 310 Hingham, MA
When lubricating the valves, is there any concern with getting residual lube into the systems these values are feeding? Maybe a dumb question but this is new territory to me. Also @JK_Boston_Catalina310 have you been using the in the water product? I figure you have to be the extreme tester for all things C310 right now.
I use the regular lubricant. I undo the hose clamp and take the hose off the seacock. Then you can lube and work it back and forth. Some water comes in but it's not a big deal. I also have an alarm set to go off the same day each month to remind me to exercise the through hulls.