As you stated, you boat is over 20 years old. Any type of equipment that age requires inspection and maintance to keep in good working order. It would probably be a good idea to give the entire boat a through inspection if you haven't done so recently. Maybe even take it entirely apart so that you can look at the hulls and crossbars in detail.

There were issues with some of the 18s from around 1985. The hulls failed at the front cross bar connection. I suspect that if your hull hasn't failed by now, you're probably ok. But, be sure that you have the upgraded hull flange reinforcements which bolt directly into the side of the hull. These go both at the front cross bar and shroud connection points. There is also a fiberglass reinforcement procedure that is described in detail on the Hobie Cat forum. Check the underside of the flange (lip) for cracking. Also, check the decks for soft spots and repair if necessary.

Also, as others have said, replace your shrouds and shroud anchor bolts. If you're still using the originals, you are well overdue.

sm