Gasket or Caulk for the Leads Track ?

[domingodp]

I have removed the leads track in order to paint the deck. There was only caulk under the track and it was leaking (have never been recaulked). What is recommended ?...Thanks, D

[sailingdog]

I would counter sink each of the fastener holes a tiny bit. Then I would bed the track with your choice of sealant. I'd use 3M 4200 or 5200, but your choice may be different. Put the track down and tighten the fasteners finger tight, and let the sealant cure. Once the sealant has cured, then snug down the fasteners by turning the nut underneath, while holding the bolt or screw stationary, so as not to break the gasket formed by the sealant.

If you don't have access to the underside, then you will probably want to do the same steps above, but before snugging down each fastener, remove it, dab some more sealant around it and then snug it down to its final tightness.

The slight countersinking of the holes allows the sealant to form a tiny o-ring like seal at each fastener. YMMV.

If this is going through a cored deck, you will probably want to check to make sure the holes are potted.

A potted hole is one that was drilled a bit oversized, and then filled back in with thickened epoxy, to seal the deck core and give the fastener a solid material to tighten against, and then re-drilled with the proper size bit for the fastener. This is very labor intensive and generally not done...but if you're going to do the damn job, might as well do it right. BTW, potting the fastener holes and applying the sealant in this manner usually means that any water that does get by the sealant just leaks into the cabin relatively harmlessly, and doesn't dampen the core and cause core rot and delamination.