Meant to post this a couple of week ago. I have some minor water leaking into the aft cabin from the thru bolts on the starboard primary winch. The area right around the winch also displayed high moisture readings but no signs of delamination with a percussive sounding with a hammer.
I removed the winch about a month ago by using adhesive remover and a putty knife. I have to say that winch was on there well. The bolts did come out easy though.
After removing the winch I cleaned up the surface and did some probing of the thru bolt holes in the deck to see if I tell if there was any core damage. I also expected to find some type of metal plate in the deck at that area based off some other posts but I could not detect any plate with a dental tool that I was probing with.
So the bolt holes have been exposed for over a month and I can not detect any moisture / rot by probing but the moisture meter still shows quite a bit of moisture in this area. About a 2 foot section. I thought it might be caused by something in the core of the deck that could be mucking with the moisture meter but the port side shows a reading of zero.
Before I rebed the winch I want to make sure there are no other problems.
Anyone have any experience with high moisture readings in this area of the boat.
One other thought I have was possibly water intrusion from the little cubby hole / box right below to the rear of the winch. Just throwing things out there at this point.
Also I am assuming that I should both use butyl tape for the rebedding of the bolts that go through the deck but also use 5200 to adhesively seal the winch to the deck.
Attached is pictures of the winch before removal and the deck surface after.
Thanks for the feedback.
Ralph Rye
1999 C36 MKII - Tall Rig - Fin Keel
Hull#1813
Green Bay, WI
Ralph,
You have a couple of options and neither would include using 5200. If probing of the core does not reveal rot, I would move on to rebedding the winch....if your boat has been covered forthe winter (and the bolt holes exposed), it would seem that the core would be dry enough....but I'll let others comment on the moisture level.
To rebed the winch, the belt and suspenders approach would be to prevent any water from entering the core again. To do this, you would overbore the exiting holes, fill with thickened epoxy, let it cure, then redrill the exisitng diameter holes and mount the winch with the bolts. I would still bevel the top part of the hole and use some butyl tape in this area and around the head of the bolt to seal from water penetration. IF water would get in it will not absorb into the deck. Do NOT seal the underside of the hole.
The other option is to just use the butyl and skip repotting the hole with epoxy. The thru-bolts hold the winch in place, so an adhesive like 5200 is not needed or recommended.
Stephen Kruse
Kruse Control #1428
1995 C-36 MKII SR/WK
Lake Lanier, Ga.
What Stephen is suggesting is reasonable. Skip the 5200 and just use butyl. The majority of force on the winch is shear and the bolts are doing the work. A couple of thoughts:
Given that the winch was bedded in adhesive, is on a slope, and you have a 2' section of moisture, you might consider other sources of moisture ingress. Someplace where water is trapped / allowed to pool, or a fixture that flexes are prime suspects. Could be that the winch bedding was never that good to begin with. You'd be the best judge here.
Your moisture readings might be artificially elevated by cold weather. Not to say that there is not moisture present. Even though you had the bolt holes exposed for a while, cold weather might have slowed down evaporation.
Consider a backing plate for the winch, or at least use oversized washers. Only apply butyl to the underside of the winch, the chamfered bolt holes, under the bolt head, and around the bolt grip that extends into the chamfered holes. Don't apply any sealant to remainder of the bolt grip or to the backing plate/washers. Early leak detection is better than undetected leaks festering for years....
Nick Caballero
Retired C36/375IA Mk II Technical Editor