I'm replacing the factory nylon thru-hulls in my boat with stainless and was wondering about fit-up. The holes in the hull are 1 1/2" on the nose. Yet I find that there are no thru-hulls out there measuring 1 1/2" O.D? I have 1 1/8" hose running to these fittings and all the fittings I find for that size hose measure either 1 5/16" or 1 3/8" O.D. That leaves a gap around the thru-hull and the hull itself. Am I to believe that that area is designed to be filled with sealant for vibration resistance? Durability? I can't see how that is correct. The fittings I removed had a 1/4" thick "spacer" ring of sealant around them if that makes sense. I want to re-install the fittings and make sure they are snug in the hull. So, my two questions are:
1) Why the size differential?
2) What sealant to use to seat the fittings? These fittings are submerged at times when I am in my boat.
UFM82
1) Why the size differential?
2) What sealant to use to seat the fittings? These fittings are submerged at times when I am in my boat.
UFM82