H-18 Mast Plug Replacement

Drill out rivets to release goose-neck and downhaul cleats. Start with a larger drill bit 3/8" and a variable speed drill. Drill carefully so as to only drill the head off of the rivet. Do the same with mast base. Punch all rivets through the holes and remove the Mast Base. You will probably have to use a flathead screw driver and a hammer. Gently tap the mast base near the halyard pulley and work your way around the base until it comes free, then remove. Loosen Diamond wires and remove the bolt going through the mast that holds the mast rotator in place. The plug surrounds the bolt and is a source for leaks into the mast chamber. Therefore I opted to reinstall the plug above the bolt to improve my chances of getting a water-tight seal.

I used a long thin screw driver and manipulated it through bolt hole to push the plug out the end of the mast. You may be able to accomplish the task easier with a cork screw tapped to the end of the dowel. Once the plug is removed, drain any fluids that may be trapped behind the plug and prep for reinstall. This is where I had to make a couple of my own tools. See Photos...

I precut a 1/2" (inner diameter) plastic tube to 24". I used a 36" piece of aluminum that I bent the end of as an extension to the caulking gun. I tapped the tube to the aluminum and to the caulking gun and cut the end of the caulk tube far enough back to allow for maximum flow. I used a large pot and heated the water, then I put three tubes of latex caulk in the pot and heated for a couple of minutes only. I laid a generous bead of caulk on the inner walls of the mast. I also put down a large bead of caulk on the inside of the plug (back side, or the side that will face the watertight chamber of the mast.) I used a 1 1/2" PVC pipe about 4' long as a packing rod, to push the plug into place. I then pushed the plug into place about 1 1/2" past the mast rotator bolt hole. This is where it got kind of tricky for me, and why I had to improvise with the caulking gun.

I had someone hold a flashlight on the plug and with the extended tube of the caulking gun I ran several beads of caulk over the bottom side of the plug. I then used a yard stick to even out the surface, forming a consistent layer of latex over the whole surface. Allow sufficient drying time, and then replace the hardware. I use caulk and the rivet caps to ensure a watertight seal on all rivets when installing the hardware. Good Luck. Email me if you have any questions at opwan2002(at)yahoo(dot)com