1985 Outrage 18' Bow Chock Fasteners

[drreid]

I finally replaced my crumbling rub-rail, and that project now looks great. In the process, however, I had to remove the bow chock and encountered the result of our salt environment on stainless steel screws installed [more than] 30-years ago into the threaded aluminum plate that is buried inside the fiberglass bow decking. Even after a week of dripping rust-cutter oil onto the screws, then trying carefully to apply a hammer drill to dislodge them, all I managed to accomplish was twisting off the screw heads. I hope to reinstall the bow chock with sleeve or barrel nuts, if I can identify the screw diameter and thread size of the broken off screws. Can anyone, here, provide these OEM measurements?

[jimh]

Since you appear to be planning on threading barrel nuts onto the studs of the remaining parts of the bolts, you must have access to the threaded portion. You could be able to identify the diameter and pitch, if not visually, then by testing a few different nuts on them. I would expect they'd be standard SAE threads, so probably something like 10-32.

[drreid]

Thanks, Jim. I used a 5/8-inch hole saw to drill out some room around each screw stub to get a good look, as you suggested. West Marine had some stainless barrel nuts in 1/4 x 20 that perfectly fit the old twisted-off screw ends. I was lucky: the screw ends fit into the barrel nuts requiring only some minor on-off thread cleaning with one of the nuts. To fend off moisture I cut a gasket sized to the underside of the bow chock using some 1/8-inch-thick neoprene sheet stock. The repair looks good and does the job. No worries, now.