I know they all make noises at idle but this one started to sound like a warning noise like a car alarm beeping then the engine started to idle higher like it saw ready to start moving but it didn't. What is that rambo1...
What was the exterior temperature at the time?
Never too old to have a happy childhood!
about 5 c
It could have been a low temperature alarm, where the computer detected the coolant temperature had fallen below the minimum and the computer advanced the throttle to increase heat transfer from the operating engine to the cooling system and thus raise the temperature of the coolant above the minimum. When the proper coolant temperature is reached, the engine's throttle will return to idle.
My company has instructions for locomotives that are not equipped with 'Automatic Start/Stop' units, that when low temperatures are forecast, and the locomotives left running should be left in the 3rd notch to prevent the coolant temperature from dropping too low. The coolant temperature also affects the oil temperature of the engine and lower oil temperatures generally make the viscosity of the oil higher and it may become too viscous to adequately lubricate the engine since locomotive lube oil is much more viscous than the 10-30 we are familiar with in automotive applications.
The only thing I can think of is that is the buzzer warning people around the unit that it is about to start.
There are no other warning beeps or such that I can think of on our SD70M-2's.
10000 feet and no dynamics? Today is going to be a good day ...
I heard something very much like this on Norfolk Southern the other day. Unit (in trail) was idling on a siding, and would slow down, seeming to 'stumble' a bit, and the beeping or warbling tones would start. After a few seconds the engine would go to higher idle (and smooth out) for a period of about a minute.
I was thinking engine temperature, too, with the system (whatever it turns out to be) just going to a fixed higher idle rather than adjusting idle speed to temperature. I suspect it's a "backup" system of some kind.
Auto start/stop. Sometimes the engine itself cancels the process of shuttng down, or a crew member can do it manually.
The opinions expressed here represent my own and not those of my employer, any other railroad, company, or person.
I don't know what you guys are hearing because I can tell you with 100% certainty that the locomotives do not give any warning what so ever when they go into high idle to warm up the engine.
No but if they are going into autostop mode they do. And if smeone on the cab wanted to cnacel the stop, he coudl either toss the reverser or advance the throttle.
traisessive1 I don't know what you guys are hearing because I can tell you with 100% certainty that the locomotives do not give any warning what so ever when they go into high idle to warm up the engine.
zugmann No but if they are going into autostop mode they do. And if smeone on the cab wanted to cnacel the stop, he coudl either toss the reverser or advance the throttle.
This would make sense for the situation I saw -- the train was waiting at the south end of a siding, on the main, for a signal to clear. Makes sense that the crew would keep cancelling a fuel-saving shutdown. I was thinking in terms of automatic response to a situation, not a manual response to an undesired automatic one!
If this adds anything: the alarm went off as the engine went to high idle, so I concluded the alarm was for some condition that going to high idle 'cured', not a warning that the engine was going to be accelerated.
Sounds like a crew member punching the AESS reset button to prevent the engine from automatically shutting down. It's a fuel saving measure. The AESS (Automatic Engine Start/Stop) computer will shut down the engine if it's been idling with no throttle/reverser input for a specified period of time. A beeper will go off first, to give the crew the opportunity to punch the reset button (on the back wall of the cab) to delay engine shutdown again. Reminds me of the Windows PC automatic updates, where you have to click the button to keep your computer from automatically shutting down to install updates. :P
Our community is FREE to join. To participate you must either login or register for an account.