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Seal SJ23 Stanchion or Pulpit Foot & Mounting Bolts. (under construction)
 

Moist air will find its way inside a hollow stanchion through the lifeline opening.  It's doubtful that moisture can get inside the pulpit unless you have drilled into it.  The same goes for the pushpit I fabricated.  Both are sealed but be wary of a pin hole leak.  The moist air condenses inside when the air temperature drops below the dew point.  Then the water collects at the bottom.  The water can accumulate to a significant amount because it NEVER evaporates.  Sealing the bottom of a stanchion to the deck aggravates the problem by preventing the water from draining.  Failure to let this water drain out will lead to corrosion and later splitting a tube with each freeze / thaw cycle.  I feel that the freeze / thaw cycle also breaks the sealant free from under the foot, resulting in a leak that goes though a bolt hole into the cabin.  I confirmed this with a vigorous shake of

STANCHION - Sealing a stanchion foot to the deck is seldom a problem as the wide foot provides lots of space for your favourite marine sealant (Sikaflex, 3M 4200, Butyl Rubber, etc).   Fortunately the stanchions have a drain hole at the bottom to let water out.  This is precisely why you shouldn't seal the entire underside of the foot.  Leave a passage through the sealant for water to flow out on deck. 

SOLUTIONS
1 - The first technique that comes to mind is to circle seal each bolt hole, leaving a space between them for water to flow.  If you think the air gap isn't open enough, lay a SS flat washer over each bolt hole to limit squeezing the sealant out and to maintain the stiffness of the stanchion.  A 1/16" wide air gap is more than enough.  Bevel the top of the deck hole, the washer and the top of the foot prior to applying all the layers of sealant it will take.  Remove the excess after assembly for that professional finished look.
2 - A tiny tube imbedded in the sealant might work.  I haven't thought this one through.

Regardless of which technique, you should be able to poke something in there to keep the gap open.

PULPIT / PUSHPIT - Sealing a pulpit or pushpit foot is seldom a problem as both have wide feet for your favourite marine sealant (Sikaflex, 3M 4200, Butyl Rubber, etc).  Of all these feet the only ones that matter are the aft feet of the pulpit as a leak there goes directly into the cabin.  A leak at the other feet goes into the anchor locker or into the cockpit locker.  Unfortunately the pulpit does not have drain holes at the bottom.  If you drill a hole through the foot, similar to a stanchion, then don't seal the entire foot to the deck.  Leave a passage through the sealant for the water to flow out using SOLUTION shown above.  Alternatively you could drill a 1/8" drain hole at the bottom, low side of each tube. 

If the pulpit has never been off, then expect a lot of old sealant and dirt under the feet.  It's best to reseal them one leg at a time.  Removing the pulpit entirely makes putting it back on difficult.  The metal assembly has a lot of memory making it difficult to align to the mounting holes without messing up the sealant.

MOUNTING BOLTS - The mounting bolts through a stanchion or pulpit foot are a different matter.  I have several on Panache that defy sealing and I'm tired of sponging up the water in the settee bilge.  The bottom of a bolt head is seldom a smooth surface and sometimes a bolt goes through the deck at an angle.  Neither of these situations is conducive to creating a good seal.  To aggravate things, you know that movement can break a seal so your instinct tells you to tighten the "bejesus" out of the nuts.  After all, movement causes a deck leak don't you know!  Then you come up on deck to discover the sealant was squeezed out from under all the bolt heads you just tightened.  This is quickly becoming a bad day. 

You could increase the holding power of the bolt head by using a flange bolt that has slightly more surface area under the head, if there is space for the flange.  Failing that, I've stuffed sealant around the outside of a bolt head as a desperate solution.  It looks ugly but there are times when you just have to do a temporary fix.  If it actually keeps water out then somebody is looking after you!  You have limited time on a buckshee fix, so time to git to it! 

INSTALLATION - Get a buddy to help because you don't have the arms of an orangutan to reach between the deck and the nuts below deck.  In any of the following techniques, bevel the hole below the sealant then sanitize the surfaces with acetone before you apply any sealant.

• Butyl Rubber under Bolt Head - Sanitize the surface with acetone, roll up a bead of butyl rubber and form it into a cone under the bolt head.  The book will instruct you to tighten it to final spec at time of installation.  I have never found this to seal a bolt for multiple years.  Problem is, it is leaking and needs to be sealed now. 
• Sealant under Bolt Head - The prescribed technique with a sealant is to sanitize the surface with acetone, apply the sealant in a cone under the bolt head, tighten the bolt to just snug, wait 24 hours for the sealant to cure, tighten to final spec. 
• O-Ring with Butyl Rubber under Bolt Head - I have often wondered how effective an O-Ring under a bolt head would be.  Roll it up the 1/4" bolt shaft to under the bolt head.  O-rings generally come in 2 sizes; use the thin size so the bolt head doesn't stick up so much.  Then pack a cone of butyl rubber under the bolt head, totally covering the O-Ring.  Bevel the top of the bolt hole in the foot.  This combination should make a good seal that can be snugged up at installation time and retain enough of the butyl rubber.  I see no reason why it wouldn't stay sealed over a wide temperature range; from -35C to 30C (the minus one is for storage).  After all, this is exactly what I did to reseal Panache's windows that have stayed bone dry since 2005.  See Tech Tip B05.    NOTE - I sealed a leaky bolt in 2025-05-28.  I'll wait for the next rain storm to see if is a success.
• Gasket under Bolt Head - This technique is really no different than the oodles of gaskets you find in automotive engines that are sometimes backed up with an application of Permatex Form-a-gasket to seal tiny cracks.  A rigid gasket will work if the metal mating surfaces are machine smooth.  A softer gasket will work for a slightly rough surface.  But I doubt a gasket will work if the mating surfaces are on different planes (crooked bolt).  I haven't pursued this idea any further.
• Specialty Bolt E/W O-Ring under Head - This is a special bolt that has a groove under the head for an O-Ring.  You tighten it to final spec at installation time to squeeze and seal the O-Ring.  I have not seen these bolts in SS but this gave me an idea.
   

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