As with all things mechanical there is a constant deterioration of the various parts. At some point these creations fail to perform. Additionally every mechanical device conceived requires a minimum level of maintenance and TLC. This holds true for the diesel powered electric generator.
Wet Stacking of Diesel Generators
In past blogs, we have covered wet stacking; the accumulation of unburned fuel in the exhaust system. This is due in part to light loads causing the engine to run below optimum operating temperatures. Bluish smoke indicates the combustion of oil. Another indicator is excessive consumption of lubricating oil. Oil enters into the combustion chamber from poorly seating or worn rings and around valve seals. Wet stacking may be the culprit. Oily, gooey residue around or in the exhaust with bluish smoke or excessive oil expenditure may indicate long periods under light loads, with poor ring seating. Of course valve guide wear and deteriorating valves seals may contribute to ‘blue’ smoke. With low combustion chamber readings, a engine rebuild is probably due. Worn engines burn more fuel compared to the load than a healthy engine.
Burning of Excess Fuel in Diesel Engines
Black, sooty smoke indicates burning of excess fuel. Diesel engines tend to be ‘lean burners’. Engine speed is governed by how much fuel is being injected. There is no throttle valves creating a vacuum condition as in a gasoline engine. Air flows into the engine and the more fuel the more power. That is why diesels provide no breaking ability for trucks. It is estimated that a diesel at low idle is producing nearly 80% of the energy when being driven down a grade. So black smoke indicates a ‘rich’ condition where more fuel is being introduced than the load requires. Dripping injectors have been known to produce smoke on acceleration from a stop, because worn injectors are dripping fuel into the cylinder under idle conditions. Metering control is down because the injector tips are worn.
Diesel Generator Troubleshooting Guide
Troubleshooting a diesel generator is a learned skill and to be good require some experience. Some of the maintenance and troubleshooting tips are:
• Running hot? Check coolant levels. Low coolant levels, usually a mixture of water and glycol, will allow heat levels to rise over normal. Before start up always check fluid levels. Coolant, lubricating oil and fuel. Some leakage is to be expected, but if you find your levels low on a regular basis you may want to consider an external of internal leak. Crack heads or block will allow water into the cylinders and into the oil pan; neither condition is an acceptable operating condition.
• Cold start? Install a block heater An installed block heater saves time, frustration and excessive deterioration of engine components. Even in warm climates a block heater thins oil and raises the block temperature to allow for easier start-up.
• Leaks? Fuel, coolant & lubricating oil leaks are common. Vibration and deterioration of seals and gaskets are a result of regular operation. Coolant hoses need to be changed every two to five years. Fuel wetting and leaks can be the result of O-ring, seal or gasket failures or wet stacking.
• Leaks or check valve failure will lead to hard start ups. Fuel gauges may fail leading low fuel levels or out of fuel states.
Well Maintained Diesel Generators are Vitally Important
Check the engine prior to every start. A visual inspection will reveal developing problems, and fuel level, oil and coolant checks will prevent many issues. Running out of fuel an hour into the work day is expensive. Best to fuel the evening before and check again before start-up. Engines and generators need care and maintenance to perform efficiently and reliably. Contact Environmental Power Solutions to rent, lease or buy an excellent quality and cared for diesel generator!