Look at the hull for dents and cracks in the gel coat (especially along the seams around the cockpit).
Check whether any water has got into the hull.
Look for any soft spots in the hull, look along the hull for any depressions, if there are, push them to see whether there's a soft spot.
Check out the rudder cables; take the tiller bar cover off and check for corrosion.
Rob
Currently Fenn Swordfish S, Epic V10 Double.
Previously: Think Evo II, Carbonology Zest, Fenn Swordfish, Epic V10, Fenn Elite, Red7 Surf70 Pro, Epic V10 Sport, Genius Blu, Kayak Centre Zeplin, Fenn Mako6, Custom Kayaks ICON, Brian's Kayaks Molokai, Brian's Kayaks Wedge and several others...
