Run Your BUS! Weekly!

[prof.fate]

I recently began driving school buses (the kind with kids on them) and teh one I drive is a BB/International with a Dt466e.

After christmas break (about 12 days) I noticed for a couple of days that my bus seemed low on power..so I mentioned it to the boss.

Yep, he says, the turbos gum up and can take a few days (150-200) miles to loosen up.

Over the summer it's worse - they run the buses weekly because they've found if they sit 2-3 months they'll have a turbo or two (out of 16 buses) seize up.

[Dapplecreek]

Originally Posted by prof.fate

...they run the buses weekly because they've found if they sit 2-3 months they'll have a turbo or two (out of 16 buses) seize up.

There's 'running' and 'running'... for the turbo question, do they let 'em idle for 20 minutes or run 'em down the freeway for an hour?

[cadillackid]

heck I drive my busses all the time.. when im in Ohio RedByrd is what I go to pick up pizza, get groceries, go to the office, meet friends for coffee.. tried to Valet it once but the valet freaked out and they let me park it where all the ferraris park..
-Christopher

[Dapplecreek]

Originally Posted by cadillackid

heck I drive my busses all the time.. when im in Ohio RedByrd is what I go to pick up pizza, get groceries, go to the office, meet friends for coffee.. tried to Valet it once but the valet freaked out and they let me park it where all the ferraris park..
-Christopher

Oh, were I to have a bus I think I would want to drive it all the time just like you do! But it would add another ten bucks for fuel for the drive in to work each day, and I don't know how that would go over. Looking for reasons to push for it...

[prof.fate]

they go drive em on the roads for 1/2 hour.

[juliol]

Hi guys, this is a stupid question, but I have a cat 3208 with turbo and I drive it two weeks of each month back and forward to work to keep it running, honestly I do not feel any difference or can tell if the turbo works, how can I tell if the turbo works?

J

[GreyCoyote]

If the turbo was completely gronked, you'd be rolling coal (spewing black smoke) and have a serious lack of power. The entire bus would feel miserable and out of sorts, and the mileage would be very, very poor. With an electronic engine, you'd have a light show on the dash.

At least in my bus, at part throttle you can hear the turbo whine very clearly, and as you throttle-up, the noise frequency goes up quickly into the inaudible ultrasonics. (Love that noise! Hehehe)

If you suspect a turbo problem, a cheap pressure gauge plumbed into the manifold will tell the tale. That gauge should move smartly upwards when you put your foot into it. In mine, I get about 18 psi of boost at 2400 rpm at open throttle.

[Elliot Naess]

First time I have heard of turbos failing from sitting parked.
Millicent sits for up to several months every winter, ten winters and counting.

I run full synthetic oil, which may be beneficial.

[Alan N]

My diesel guy says there is an oil seal in the turbo on a 3208 that can " stick" after sitting for a while causing lots of smoke (and disappointment).
I know this because I started my bus after it sat all winter and it smoked badly.
I thought my engine was kaput.
After the initial panic l took it for a spin and thankfully the smoking quit.
So run your bus when you have a chance.
The experts say to get it up to operating temperature for a half hour at least.

[Elliot Naess]

I don't disagree with that. Sitting is never good for any vehicle. For example, I have had cars develop mold inside from lack of ventilation. And engines can also suffer from moisture. And rubber parts such as seals can indeed take a set in one position.

It's that ruining of turbos that I question.

On this note.... I invest a lot of time in ventilation. I watch the weather, and on dry mornings I open Millicent's windows -- they have screens -- and close them in the evening. In truly dry weather I leave them open 24/7.

And after rain, I open the tailgate and front door also, for weeks, if possible. Cannot keep birds and bugs out with those open, but moisture is a killer. I suppose I ought to have screens for those also.

[cowlitzcoach]

I have been in the bus industry for more than 40 years. I have never heard of turbos getting gunked up and not working correctly after they have been sitting for a while.

I think perhaps the problem lies more in how the buses are operated.

If all you do is start your bus and run it at fast idle without moving it you are actually doing more harm than good. The engine will never get up to the proper operating temperature. Because it isn't working hard and not getting hot you will not burn all of the fuel that is injected into the cylinders. That unburned fuel will get past the rings and dilute your lube oil.

On newer buses with regen cycles and afterburners the need to get the engine up to operating temperature is even more important. If you don't get them warmed up enough the emissions systems get all coked up and can cause sluggish throttle response, lack of power, and smoke. Most of it can be eliminated if you get the exhaust temperature up there towards the red line and the water temp up into the operating temperature range.

Back in the day I can remember driving a 1990 TC2000 with a 190 HP Cummins 5.9L and AT540 power package. I had seven components to my daily assignment that added up to an 8-hour day. The average mileage I drove was 27 miles per day. Just about the time the engine really warmed up I was shutting the engine off. The only saving grace for that bus was I did a lot of trips with a minimum of 100 mile round trip. A trip with a good hour in each direction with a load at highway speed kept that bus running better than most of the other buses that were identical to it.

If your bus is not road worthy then the best thing for you to do is make sure the coolant is adequate for the coldest weather you will experience, make sure the coolant pH is close to neutral, and then seal off the engine--close off the intake and the exhaust to keep critters out. Putting it to sleep will be much better for it than to fast idle it for extended periods of time.

[dalez]

Second the above. Fast idling the engine will never get it hot enough to boil moisture out of the oil, lets fuel and smoke past the rings into the oil, probably increased friction while running due to wider tolerances and cold oil... Unless you drive it and get it good and hot and keep it that way a while, better to leave it cold. Hell if I just leave my engine idling for 5 or 10 minutes after a drive it'll start puffing smoke out of the crankcase vent because the engine has cooled off =\

[cadillackid]

I agreee with fast idle.. I was working on my Red Bus today. where im chasing down and air system problem / coolant issue. and it mustve been running in high idle for an hour and the temp gauge was just about 180.. I then took it out and ran it up on the freeway where it got up to its full operating temp.. I only had one heater turned onto level 1 fan the whole time I was working on it too.. so they definitely wont warm up sitting still..
-Christopher

[SDR76]

Ive never heard of a turbo going out from sitting. However, I did take the bus for a spin the other day and I had a ton of smoke. Ive been working inside the bus for the last few months; Id go start it, turn up the heat and the tunes and get to work. I don't know how many hours of idling it has done. Once in a while Id roll around the neighborhood just to keep things lubed. But the other day I decided to run it a bit harder, WOW- I was rolling more coal than West Virginia coal train!! I laid into it hard for about half a block, It blacked out the sun for a moment, but clean up nicely after that.... This was on a 1990 BB- 5.9 Cummins.