2. Room Temperature (Cooling)
The single largest catalyst for Marine Diesel Engines mechanical issues is not technically a part of the engine. The fact that this integral aspect of your power plants operation is not ever covered by warranty should help you understand the importance. Impeded and clogged sea strainers are without a doubt the absolute #1 cause of failed marine diesel engines. Fouled and dirty strainers impede raw water from their natural abilities to properly cool the fresh water system. This single aspect causes the whole system to get thrown out of whack and will overheat your engine in a heartbeat. Just as water is vital to human life it is equally important to your engine’s health. By the time the dummy alarms or idiot lights come on some damage if not catastrophic has already been done.
A typical marine diesel engines cooling system is made up of 2 very basic components. The raw water system first brings in the seawater or river water through an opened seacock via an in line pump. The water goes thru a lube oil cooler first and then on to the heat exchanger. This is where the vital aspect of cooling the engine’s fresh water takes place. The water then begins the journey thru the mixing elbow, this is where it cools the 1,300 degree Fahrenheit exhaust gasses before making an exit thru the complicated exhaust system. Remember all 4 of these Marine Diesel Maintenance Tips are basic in nature and designed to assist you in getting the most out of your engine’s life. If you have any issues with your exhaust system please call Diesel Services of America immediately.
A typical freshwater system for a Marine Diesel Engine is made up of several components. First a closed loop that pumps the water from within the reserve tank to outer cylinder jacket, then the turbocharger and finally the cycle head. Once you have started your engine, the thermostat in the system will regulate the valve that cycles the very hot water thru a heat exchanger, where then it is cooled by sea water. A key piece that fails regularly on almost all pumps over time is the impeller. A properly working pump impeller resembles a gear with blades, this gear is constantly starting and stopping and being worked in all directions. Thus giving the impeller a better opportunity to fail more often than other parts on your marine diesel engine. Your impeller will absorb the sea water gradually over the course of time making it much harder and brittle. This causes the blades to warp, bend and break off, anyone of these actions will cause your pump to product the full amount of water which your marine diesel engine requires. Most Marine Diesel engine manufactures and Diesel Services of America highly recommend removing the impeller annually. Once fall is upon us remove the old impeller and put in a new one every spring. Again if you’re not comfortable lugging around big wrenches and working in boiling hot engine rooms, let Diesel Services of America take care of this for you. Taking the raw fresh water pump does require a specialty tool to remove the pump from the block. A basic socket wrench can do this but you need a specialized impeller removal tool to remove from the housing. By the time you spend the $150 on the removal tool you are going to probably wish you had called Diesel Services of America. Very important step before you insert the new impeller, liberally coat the insides of the raw water pump with the provided glycerin or a very popular substitute extra virgin olive oil.
The next part is crucial to proper marine diesel engine performance. When re-attaching the pump it’s much more complicated than removing. Every single last bolt on any marine diesel engine requires a specific torque specification and appropriate tightening sequence. Even the hose clamps must be properly secured. Follow the exacting guidelines of the owner’s manual for your marine diesel engine model. Again you will need certain tools specific to this procedure, in this case a torque wrench. By the time you have purchased the impeller removal tool and torque wrenches you might have wished you had called Diesel Services of America.
