An empty cooling jacket will act as an insulation to the stuffing box fluid. Remember that the cooling jacket is also there to cool down the shaft and protect the bearings. Do not disconnect it. When you look for corrosion be sure to check out any cleaners or solvents that are used to flush out the system or clean the lines. It is important to identify all of the materials used in the seal components.
Plated materials can crack due to differential expansion.
Stainless Steel springs can break due to Chloride Stress Corrosion. Hardened set screws can corrode and vibrate loose. Some elastomers can be attacked by steam. Be careful of using petroleum grease on elastomers as some compounds can be attacked by any petroleum product. Some hard coatings have very little flexibility and will crack with a small differential temperature.