Section 137.330 - Scope of the drydock examination(a) This regulation applies to all towing vessels covered by this subchapter. The drydock examination must be conducted while the vessel is hauled out of the water or placed in a drydock or slipway. The Coast Guard inspector or surveyor conducting this examination must:(1) Examine the exterior of the hull, including bottom, sides, headlog, and stern, and examine all appendages for damage, fractures, wastage, pitting, or improper repairs;(2) Examine each tail shaft for bends, cracks, and damage, including the sleeves or other bearing contact surfaces on the tail shaft for wear. The tail shaft need not be removed for examination if these items can otherwise be properly evaluated;(3) Examine the rudders for damage, the upper and lower bearings for wear, and the rudder stock for damage or wear. Rudders need not be removed for examination if these items can be otherwise properly evaluated. This also includes other underwater components of steering and propulsion mechanisms;(4) Examine the propellers for cracks and damage;(5) Examine the exterior components of the machinery cooling system for leaks, damage, or deterioration;(6) Open and examine all sea chests, through-hull fittings, and strainers for damage, deterioration, or fouling; and(7) On wooden vessels, pull fastenings as required for examination.(b) An internal structural examination required by this part may be conducted while the vessel is afloat or while it is out of the water. It consists of a complete examination of the vessel's main strength members, including the major internal framing, the hull plating and planking; voids; and ballast, cargo, and fuel oil tanks. Where the internal framing, plating, or planking of the vessel is concealed, sections of the lining, ceiling, or insulation may be removed or the parts otherwise probed or exposed to determine the condition of the hull structure. Fuel oil tanks need not be cleaned out and internally examined if the general condition of the tanks is determined to be satisfactory by an external examination.