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80-RE4
Top Member
USA
5700 Posts |
 Posted - 02/15/2003 : 9:32:04 PM
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On very very cold nights/days, our busses are started by the overnight bus crew at 11 pm. Does that do any damage to a bus being on for so long? From 11 pm to about 9 am? Just sitting there doing nothing?
I love my Amtran RE ;-) |
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Miss_Myra
Senior Member
USA
92 Posts |
Posted - 02/16/2003 : 07:16:45 AM
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I can't imagine a bus idling for that length of time. We have idle time limits for at least polution control. At 32 degrees or higher the idle time is 15 minutes. At 0 it's unlimited but the longest any of my buses run before leaving the yard is 45 minutes and that's now when it's well below 0. I would think it could damage the engine idling for very long periods of time.
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Skewl Bus Boi
Advanced Member
USA
323 Posts |
Posted - 02/16/2003 : 07:25:01 AM
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Diesel engines aren't hurt by extended idling. Only gas.
On really cold nights during the week we tell our drivers that on full-size diesel buses, leave them idling all night.
—Phil
Double A Transportation — "The People Movers" |
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BlueBird44
Top Member
USA
1639 Posts |
Posted - 02/16/2003 : 10:12:44 AM
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We had a contractor who was having starter problems with one of his buses. So he let his bus run from morning till night for a week. Just because he was to lazy to try to get it fixed.
I don't think many idle there buses over night the only time they really do it is when they're sitting at school.
~BlueBird44~
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Carpenter Bus_19
Advanced Member
USA
286 Posts |
Posted - 02/16/2003 : 2:31:28 PM
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if you want to idle a diesel. I suggest to run it at fast idle. or 1,000 Rpm. To keep the oil pressure up and also to keep the oil flowing to the turbo.
Luke L. C.
Operations Manager |
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wagonmaster
Top Member
USA
2298 Posts |
Posted - 02/16/2003 : 6:33:22 PM
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Running a bus for 10 hours prior to its morning route is, in my opinon, ridiculous!
Forty five minutes to an hour of idling should be adequate time for even the coldest climates. Idling builds deposits on valves and pistons and is a huge waste of fuel. Ever notice that after an extended idle period, that many diesels blow blue smoke for quite awhile? That's the deposits burning off. I would never idle one any longer than I had to.
Joe
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Peter
Top Member
USA
1057 Posts |
Posted - 02/16/2003 : 8:04:37 PM
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Given all of the budget problems that districts across the country are having, one would think that this excessive use of fuel would not be tolerated. If you're working for a contractor, this practice is even more surprising. I can hear the profit margin on that contract shrinking from here.
Joe is absolutely right: there is no reason to idle a bus that long. I've been on a starting crew before. On a -15 degree day, we began at 4 AM (our earliest routes checking in at 5:45 and latest at 6:50) and 95% of the buses started without the aid of ether. These buses ranged in age from 1989-2001. After getting them all going, it was still only 5:15 and we felt that we could have begun later.
How far from your terminal can you see the choking fog of diesel exhaust rising in the morning?
Yikes!
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cowlitzcoach
Advanced Member
USA
325 Posts |
Posted - 02/17/2003 : 06:34:39 AM
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Outside of the excessive waste of fuel, extended idling can also increase wear on the engine. This occurs mostly because at idle, even at fast idle, the fuel doesn't get burned properly.
As the fuel continues to not burn properly, the unburned fuel will start to wash past the rings and dilute the lube oil. So in addition to unburned deposits clogging up the combustion chamber and valves, you have diluted lube oil going through the whole engine.
If your buses are so cold they need to be started that soon it would seem to me a fuel fired heater like an Espar or Webasto would pay for itself in no time.
We actually idle our buses longer in hot weather to keep the A/C running than we do in cold weather to keep the heaters warm.
Most diesels I have had experience with warm up a whole bunch faster in the first five minutes of running down the road than idling for an hour.
Mark O.
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Miss_Myra
Senior Member
USA
92 Posts |
Posted - 02/17/2003 : 07:18:04 AM
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What is A/C on a bus?
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Thomasfan89
Top Member
USA
1155 Posts |
Posted - 02/17/2003 : 07:43:49 AM
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quote:
What is A/C on a bus?
Air Conditioning! Some buses in warmer climates have it and even buses not in warm climates have it! Many Special Ed buses have it to ensure a comfortable ride. I wish our buses had it!
Greg Hovan
Now is the time of year when all buses have white tops!
Visit the school bus garage: http://www.geocities.com/fordman11189/SchoolBusGarage.html |
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bbird66
Top Member
USA
881 Posts |
Posted - 02/17/2003 : 12:16:58 PM
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How about a block heater?? Mine may get 30 min. when it gets about 0 to -10 or worse.
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1983WardFord
Top Member
USA
1395 Posts |
Posted - 02/17/2003 : 12:37:40 PM
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cowlitzcoach is right, diesels warm up better when they're actually doing work instead of sitting around. One of my bosses said 15 minutes is enough idle time in the morning to get the juices flowing (and not a big waste of fuel).
It's BIG, it's YELLOW, it has RED FLASHING LIGHTS. What part didn't you see?
Ryan's School Bus Yard--www.busman49.com |
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80-RE4
Top Member
USA
5700 Posts |
Posted - 02/17/2003 : 7:25:32 PM
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I thought that was kinda rediculous too. I mean, I could see, if someone wanted to come in on a really really cold night/day at about 11 pm, start all the busses, let them run for an hour, then shut them off, then have someone else come in at 5 and start them.
I have noticed, that when my bus has been running all night, it acts wierd. You would think that the bus would have the hottest heat, being warmed up for so long, but it makes the heat worse for some reason. Also, my bus made this weird vibration noise, I've never heard that before.
I love my Amtran RE ;-) |
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80-RE4
Top Member
USA
5700 Posts |
Posted - 02/17/2003 : 7:29:09 PM
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I once drove with someone an in A/C bus on a very very hot day. It was nice, but the bus had probs. It was a handicap bus. The water temp light kept going on and a buzzer kept going on. The mechanics said it was due to the a/c.
I love my Amtran RE ;-) |
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fundybayman
Senior Member
Canada
51 Posts |
Posted - 02/18/2003 : 03:09:27 AM
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Besides seeming to be against common sense, idling engines overnite is probably contrary to recommendations in the owners manual. You know what else is the matter with this? It's illegal. The link below leads to various state laws, MA says 5 minutes maximum.
"Massachusetts Idling is limited to five minutes, except for vehicles being serviced, delivery vehicles where engine operation is mandatory, and power takeoff (PTO) applications (if emissions are minimal)."
http://www.trucks.doe.gov/plain-talk/idling-regs.html
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Miss_Myra
Senior Member
USA
92 Posts |
Posted - 02/18/2003 : 1:35:03 PM
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I have to admit that I was being a smart a$$, I know what A/C is. It would have been nice the last 2 summers that I have driven summer sports camp. Temp about 98 degrees, humidity at 82% for days on end. Sure could have used it then. I was always told they don't have A/C on buses even in the south, or in the desert, guess I'll have to tell my riders I was wrong. God bless ya if ya have A/C.
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William Johnston
Senior Member
USA
135 Posts |
Posted - 02/18/2003 : 3:12:04 PM
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I have never heard of idle times like this. Sounds like something else needs to be looked at and repaired.
William
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rswboe
Top Member
USA
675 Posts |
Posted - 02/20/2003 : 12:58:30 PM
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You need to investigate block heaters. And Phil is wrong about diesels not being damaged by excessive idleing. Diesels run cold at idle and carbon up. There is also a condition known as "slobbering" which occurs as a result long idle times. New computer controlled diesels can ramp up idle speed to maintain a minimum engine temp of 160 to reduce this. we sometimes will sart buses 30 or 45 minutes prior to the morning shift just to save ourselves the aggravation of having impatient drivers cranking batteries to death.( And the drivers think we're being nice!).
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Skewl Bus Boi
Advanced Member
USA
323 Posts |
Posted - 02/26/2003 : 1:22:21 PM
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OK, I talked to our mechanic, and you're right, it can hurt the engines a little bit. However, there have been days in the past when it was so cold no one's buses started, and the bus companies had to cancel school, regardless of the dry (just cold) roads. We are proud of the fact that every day school has been in session in our contracted districts, our buses have been on the road.
—Phil
Double A Transportation — "The People Movers" |
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Northern SBD
Senior Member
75 Posts |
Posted - 03/01/2003 : 9:48:06 PM
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I have a sticker from the manufacturer on my dash that reads that in very cold weather idling should be at a minimum of 1250 rpm or damage may be done.
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Thomas Ford 85-16
Top Member
USA
4177 Posts |
Posted - 03/02/2003 : 3:51:59 PM
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You'll be able to tell who our mechanics are in the morning. They will be the ones running around with the spraycans of ether.
That's why our older buses have ether buttons that spray ether from the can into the cylinders. The newer ones are supposedly automatic.
Stop at: http://buses.thesummit.biz
This is an industry where people brag about their times for 60-0, not 0-60. |
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SouthernBusDriver
Active Member
USA
18 Posts |
Posted - 03/09/2003 : 09:28:27 AM
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The longest i have let mine idle was 45 min.
Some of our busses will shut themselves off after 1 hour of idling.
quote:
On very very cold nights/days, our busses are started by the overnight bus crew at 11 pm. Does that do any damage to a bus being on for so long? From 11 pm to about 9 am? Just sitting there doing nothing?
I love my Amtran RE ;-)
Jason Phillips |
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80-RE4
Top Member
USA
5700 Posts |
Posted - 03/09/2003 : 09:39:53 AM
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What is esper?
I love my Amtran RE ;-) |
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80-RE4
Top Member
USA
5700 Posts |
Posted - 03/09/2003 : 09:39:53 AM
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What is esper?
I love my Amtran RE ;-) |
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cookie_in_paris
New Member
USA
4 Posts |
Posted - 04/02/2003 : 5:30:58 PM
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how come you dont plug your buses in when its cold rather than let them run all night?
Diesel engines aren't hurt by extended idling. Only gas.
On really cold nights during the week we tell our drivers that on full-size diesel buses, leave them idling all night.
—Phil
Double A Transportation — "The People Movers"
stewart mason |
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cookie_in_paris
New Member
USA
4 Posts |
Posted - 04/02/2003 : 5:34:19 PM
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how come your buses shut off after an hour? is something hooked up to make it do that?
The longest i have let mine idle was 45 min.
Some of our busses will shut themselves off after 1 hour of idling.
quote:
On very very cold nights/days, our busses are started by the overnight bus crew at 11 pm. Does that do any damage to a bus being on for so long? From 11 pm to about 9 am? Just sitting there doing nothing?
I love my Amtran RE ;-)
Jason Phillips
stewart mason |
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PHW
Top Member
USA
1345 Posts |
Posted - 04/03/2003 : 06:57:33 AM
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Remember too when idling long periods some alternators have low output at idle. If you have enough electrical draw you can slowly drain your batteries.
PHW
Child Check For Life |
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Gary E. Davis
Active Member
USA
39 Posts |
Posted - 04/13/2003 : 09:05:04 AM
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YOU ARE JOKING, RIGHT?
11:00PM AND RUN ALL NIGHT?
Who is in charge? YES, THIS WILL DO DAMAGE! NO QUESTION ABOUT IT!
Gary E. Davis |
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Buskid
Top Member
USA
3368 Posts |
Posted - 04/13/2003 : 09:32:17 AM
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I have a question about this: if idling the engine for such long periods of time does damage to the engine, how come semi-trucks and locomotives idle for such long amounts of time? Aren't the diesel engines in school buses just small-scale versions of the engines used in other equipment that runs almost non-stop?
Detroit Diesel manufactured diesel engines for locomotives, as well as semi-trucks and buses. I think Caterpillar did/does also [locomotive engines].
How is it that it damages the engines in school buses but not the other equipment?
Crown Supercoach - The “Royalty” of Pupil Transportation |
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Buskid
Top Member
USA
3368 Posts |
Posted - 04/13/2003 : 7:57:45 PM
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There are other reasons that they are left to idle.
I realize there are other reasons as well. My major in college is business and railroad operations. I just threw in the locomotive engine example as an extra.
What about semi-trucks, though? They use all the same engines as school buses, only larger with more horsepower.
This probably seems like to a trivial question to most mechanics, but I'm not a mechanic, so I'm really curious to find out why it causes damage to the diesel engines used in school buses and not the diesel engines used in other equipment.
Crown Supercoach - The “Royalty” of Pupil Transportation |
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busmonkey
Senior Member
USA
86 Posts |
Posted - 04/16/2003 : 3:31:53 PM
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Thats crazy to do and it is very hard on diesel engines to let them idle for these long extended times. This is how we are set up at our bus garage. We have an unheated and uninsulated building that stores 17 of our 24 buses and 4 buses are keeped outside and three coaches in the shop. We have block heaters in all of our buses with a temp sensor in series with it which will turn the block heater on if it gets below a certan temperture. And we do get extremlly cold weather here in Havre Montana, -40 F. at times plus add more on for wind chill factor. We have no problem starting any of these buses and the drivers are told to only idle (1400 rpms) no more than 30 minutes before there route.
If we have one of our buses go on an activty trip we tell them to let the bus idle at least 1400 rpms over night if the temperture is 5 degrees or lower otherwise the bus just gets plugged in. Remember this is only for out of town trips. I try not to let the drivers idle there buses to long or overnight in less it meets the above needs, because this lessons the life of a diesel engine a lot. Hope this helps you out.
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Our busses are started at 11 pm
