Howdy all, I’ve a question, why are diesel engines always idleing? Even during the summer I’ll see an “mu” or single loco just sitting there for hours chugging away. Can anyonwe help?
The short answer: Locomotive diesels (save for the newest ones from CAT) do not use antifreeze. The engine needs to stay running to keep the water from freezing and damaging the crankcase. Unit could also have weak batteries, and restarting the unit could be a problem (jump starting is a little more difficult than jumping your car).
Randy’s keeping the engine warm is the main reason; as he says, most older diesels do not use antifreeze. However, you will see this practice less and less – many newer diesels either have auxiliary gensets which keep things warm and charged, or have automatic equipment which restarts the prime mover when things get too chilly.
Plus it’s an old railroad tradition. When fuel was cheap and nobody cared about air polution it kept the deisels permanently ready. This habit is slowly changing. ps; Truck drivers do it too (or used to) at truck stops.
Locomotive diesels do not use antifreeze for several reasons. Cost is a major factor, the cooling system on an SD70M is a little bit larger than the cooling system on my wife’s Jeep Cherokee. Another factor is that locomotive cooling systems until recently have not been as leakproof as that on an automobile and coolant can often leak into the crankcase oil. Some water contamination in lube oil can be tolerated but ethylene glycol can break down the lube oil, leading to all sorts of problems.