Turbos on buses & big rigs?

[Slickone]

Do most large buses (inner city commuter style & bigger) and tractor trailers have turbos? It always sounds like it to me, but someone told me no. On one bus I've ridden, while ridding in the back, you hear a big woosh sound when the driver lets off the accelerator, which I figure is a boost blow off valve.

 

[DurocShark]

Quite a few diesel engines use turbos. Not for speed, but for a more flexible power band.

 

Many many diesel engines in big rigs are turboed.

 

[thomsbrain]

some of that whoosh may be them applying their air-brakes. but yeah, lots of diesels are turboed.

 

[Eli]

Hmm.. Well, the city busses here aren't turbo'd, I'm almost positive. I'd hear it.

 

[HappyPuppy]

Most all big rigs are turboed except Jimmies, they are blown.

 

[mAdD INDIAN]

Originally posted by: Eli
Hmm.. Well, the city busses here aren't turbo'd, I'm almost positive. I'd hear it.

really? maybe they use gas motors?

Our city buses are all turbodiesel.

 

[geno]

Originally posted by: Slickone
Do most large buses (inner city commutor style & bigger) and tractor trailers have turbos? It always sounds like it to me, but someone told me no. On one bus I've ridden, while ridding in the back, you hear a big woosh sound when the driver lets off the accelerator, which I figure is a boost blow off valve.

The busses around here aren't turbo'd, neither are the ones that run around my college (the city commuter busses), yet the shuttle busses that students use to go between campuses are turbo'd. Many big rigs are turbocharged, but very rarely, if ever, do I catch the sounds of a blowoff valve coming from one of them

 

[MacBaine]

Originally posted by: HappyPuppy
Most all big rigs are turboed except Jimmies, they are blown.

Who's blowing the jimmies?

 

[Eli]

Originally posted by: mAdD INDIAN

Originally posted by: Eli
Hmm.. Well, the city busses here aren't turbo'd, I'm almost positive. I'd hear it.

really? maybe they use gas motors?

Our city buses are all turbodiesel.

No, they're not gas.. lol.

I dunno, maybe it's masked by all the other noises they make? I'll have to listen next time, maybe I've just never put it together.

 

[johnjbruin]

school buses that were old school have them - i always liked that swoooooooosh sound

 

[ElFenix]

there is a reason it is called TURBOdiesel


and a lot of buses run on gas. burns really clean. plus its pretty cheap. only problem is they are louder than anything else on the road

 

[Slickone]

Originally posted by: thomsbrain
some of that whoosh may be them applying their air-brakes. but yeah, lots of diesels are turboed.

Na, it's as soon as they let off the accelerator, before they have time to braking, and you can tell they aren't braking. It's that 'blaahhh' (say it in a whisper type tone) sound. It's real loud. If you sit in the back of the bus, there's no sleeping because of it. And that's only in the Blue Bird models. Also you it whistles really loud when it accelerates. And they're quicker. The other, bigger (different mfg) buses they (MTA) have probably aren't turbo'd since I can't hear one, and they'll barely make it up a hill. I hear it in big rigs though.

 

[Babbles]

I was thinking I can't think of any time recently that I have seen a diesel that was NOT turbocharged.

 

All the city and university busses here in Ann Arbor are turbodiesels. The U-M transportation department uses biodiesel that's actually made from soy products. It smells like fried food sometimes when the busses pass.

Pretty much every city bus I've ever been on has been turbodiesel.

EDIT: from the U-M news service:

About 400 of U-M's fleet of 1,000 buses, trucks, grounds equipment and vans already are using ethanol (from corn), bio-diesel (a blend of 20 percent soy diesel with 80 percent soy product), or electricity. That's already the largest fleet of alternative fuel vehicles of any university in the country, and the largest fleet of any kind in Michigan.

"We hope that by 2003, 600 vehicles will run on alternative fuels," Cunningham says. "The advantages of using such fuels is that the electric vehicles eliminate tailpipe emissions altogether" and the bio-content fuels come from renewable field crops rather than depletable petroleum sources. Emissions of CO2 and other pollutants have dropped by several tons a year, thanks to such practices, he adds, and the purchase of fuels produced from crops has bolstered the local agricultural economy.

 

[Atomic Rooster]

Hate to break it to you, ALL large diesels are turbocharged. If they weren't, they would barely be able to move under their own power. The turbo blew on my truck once and the damn thing would barely do 20mph!

 

[Eli]

Originally posted by: BadDaddy
Hate to break it to you, ALL large diesels are turbocharged. If they weren't, they would barely be able to move under their own power. The turbo blew on my truck once and the damn thing would barely do 20mph!

Nonsense.

I'm having trouble finding out if our busses are turbocharged or not.

It looks like all the newer busses use Cummins ISL 280(which I can't find on their webpage), and the older busses use either the Cummins C10 or M11. There are also some busses that use Detroit Diesel Series 50 engines. I can't find anything about them being turbocharged, though.

This is interesting, though:

TriMet's buses travel over 26 million miles per year. That's like traveling from the Earth to the moon over 100 times. They use:

5.9 million gallons of diesel fuel each year
217,696 quarts of oil
91,104 quarts of transmission fluid, and
22,412 quarts of coolant every year.

:Q

And our city isn't really even that big!

 

[Atomic Rooster]

Here ya go Eli: http://www.cummins.com/na/pages/en/products/trucks/isl.cfm

 

[Eli]

Originally posted by: BadDaddy
Here ya go Eli: http://www.cummins.com/na/pages/en/products/trucks/isl.cfm

Thanks.

Interesting. So I know at least the newer busses in the fleet are turbocharged. I'll have to listen for that next time.

Weird, it says they use the ISL280 .. but I don't see that listed.

Can you find any relevant info on the C10 and M11?

 

[Atomic Rooster]

Here's their ISL 280 info: http://www.cummins.com/na/pages/en/products/bus/ratingstransit.cfm

You'll find info on the M11 under the military engine listing. Can't find anything on the C10. Maybe it's a Caterpiller engine?

 

[Slickone]

Originally posted by: BadDaddy
Hate to break it to you, ALL large diesels are turbocharged. If they weren't, they would barely be able to move under their own power. The turbo blew on my truck once and the damn thing would barely do 20mph!

Wouldn't that be because it locked up and was blocking the exhaust and intake?

 

[Eli]

Oh, and the reason your truck wouldn't hardly move is because often times when the turbo blows, it becomes an intake restriction, effectivly choking the engine.

 

[deejayshakur]

Originally posted by: Eli
Oh, and the reason your truck wouldn't hardly move is because often times when the turbo blows, it becomes an intake restriction, effectivly choking the engine.

i wanna see next gen buses with nitrous.

 

[Atomic Rooster]

Ok you guys win. My 20 plus years experiance driving and repairing these damn things means nothing. :roll:

 

[Eli]

Originally posted by: BadDaddy
Ok you guys win. My 20 plus years experiance driving and repairing these damn things means nothing. :roll:

Your statement was a black and white blanket statement that is obviously incorrect.

Not all large diesel engines are turbocharged.

And again, the reason you had no power in your truck isn't necessarily because the turbo wasn't providing boost anymore, it is because if a turbo fails it becomes both an exhaust and intake restriction.