corrosion accelerated with use of block heaters ?

[bjsmarine]

Any thoughts about increasted corrosion in the saltwater side of heat exchangers, of the typical marine diesel cooling system - that that uses block heaters to keep the vessel\s engines in a state of standby

 

[Metalguy]

What metal is used for the heat exchangers?

 

[bjsmarine]

heat exchanger is bronze casting with copper tubing.

problems are in the casting area.
thanks .

 

[ENC]

If the water is not circulated during the standby state, then there may not be sufficient passivation taking place on the unit metal surface. Or debris can be settling on the surface, which will inhibit passivation. Heating can accelerate corrosion and stagnent seawater is not good either. Circulating the water during stand-by should minimize the problem.

Best of Luck