There are aluminum plates laminated into the deck while the boat is being built. Upon hardware installation, the plates are drilled and tapped from above with a “bottoming tap”. No nuts are required.

Try using our product “Freeze Off Penetrating Lubricant”, #Z4062, found below under “May we also suggest”. Apply several times over a period of days. Each time the product is used it not only penetrates into the corrosion in an attempt to loosen it, it also chills the fastener. This causes the fastener to contract slightly in an attempt to crack the corrosion. After several applications, attempt removal with a screwdriver. Do not strip the head! If this fails, use an impact screwdriver, a hand-held tool that you strike with a hammer. It rotates the head at the same moment you drive the bit into the head.

If, after attempting all of the above steps, you still end up stripping the threads in the plate, you have two potential alternatives: 1) Drill through the plate all the way into the interior of the boat. 2) If the raised pad has enough space to rotate the hardware and drill new holes without the hardware hanging off of the raised pad, you might be able to drill and tap new holes. You must move the fastener hole about 1.75 x the hole diameter for this to be successful.

Yes. There is a specialty fastener called a Barrel Nut that solves the problem. A Barrel Nut’s threads are on the inside diameter of a tube which extends up inside the thickness of the deck. With the threads buried in the deck, only a washer and the slightly domed head of the nut is exposed inside the boat for a much safer installation. See “May we also suggest” below for the barrel nuts.

Yes. Although it didn’t exist when your boat was built, there is now a product that, when applied to the threads, electrically insulate the stainless steel fastener from the aluminum plate. This eliminates dissimilar metal electrolytic corrosion between the two, making it easy to remove the fastener next time. Find the product “MareLube TEF 45” listed below under “May we also suggest”.