Why did all buses come with detroits?

[NonHippieBus]

 Why did every major North American coach manufacturer I can think of offer their product exclusively with Detroit Diesel 2-strokes from the 1950s until the 1990s?  MCI, GM, Prevost, Eagle et al.

Are there exceptions to this? 

Lots of interest in repowers on this board.  But Cummins and Cats have been available to OEMs for many years, but as far as I know none were factory installed until the last 20 years.

What do you think?

[TomC]

Actually, the first Eagles had Cummins NH262 turbo's (if I remember correctly) in them before Detroits. The 6V-53, 4-71, 6-71, 6V-71, 6V-92TA, 8V-71, 8V-92TA, 12V-71 were all used at one time in a bus or two. The 12V-71 with 4 spd was the original engine in the MC-6.

With both Grayhound and Continental Trailways having Detroits, all other buses just followed suit. And back in the 40's, 50's, 60's, and 70's, there wasn't another engine as compact and as powerful as the 2 stroke Detroits. Plus, they are very forgiving considering all the buses had manuals (except transit buses) well into the 80's. Hence a small injector Detroit could put up with a lot of abuse from driver's that really didn't care how they drove (Cummins tried the VT903 with not very good results). Once the Allison transmissions came into play, then the engines started to increase in power since the driver's no longer could lug the engine. Also, with electronic controls and high pressure turbocharging, the 4 stroke engines took over-mainly since the 2 stroke engines are no longer available since they were stopped being produced for the public in 1998. A 60 year run with an engine that you could have bought it almost exactly like it was in 1938 as it was in 1998 when production was stopped. Example-the 1938 6-71 produced 165hp at 1800rpm. In 1998 you could still buy a non turbocharged 6-71 with a continuous horsepower rating of 180hp at 1800rpm. An unbelievable series of engines with almost unlimited versatility-of which we'll never see again. What other Diesel engine do you know that could be produced in a 1-71 putting out around 30hp all the way up to the 24V-71TTA at 1800hp at 2,300rpm? Good Luck, TomC

[wg4t50]

TomC is correct and a funny for me, when I installed the 12V-71 in the MC7, it was very clear the install worked out very well for the 12V, it appeared the engine area was designed for the MC6 12V engine, fit like a glove.
Cummins supplied the V-555 to BlueBird school/transit types, even though they tried, the V-555 never was a favorite for anyone.
Like TomC mentioned, Detroit, made engines fit what ever you needed, staying with the 71 series, the  parts manuals for the inline 71 series is about 3' thick.
The DDC engines have been a favorite of mine for many years, oh yes, Cat & Cummins trained too, but I am happier with the old junk DDC stuff, they are so easy to make run nice.
FWIW
Dave M

[DMoedave]

Lots of history on this. There were many coach companies back in the day. Gas and diesel was plentiful and relatively cheap. Alot of gas powered units were used. As buses got bigger and needed more power GM had all the knowledge and wherewithall including the manpower and assylines after the big war. Greyhound and GM went partners to the point of exclusive and many called foul. There was an anti-trust lawsuit filed and won. Most everybody wanted what the big dog ran and they bought them. Too bad we lost some cool coach companies. Not a real completre answer but its a large subject lol.   

[blue_goose]

The detroit two cycle was the only engine that put out enough heat to heat the bus.
Jack

[luvrbus]

Most was because of head room in the back, Eagles you always had a choice of engines but operators and Trailways valued the head room with a flat floor plus they were not a bad engine or GreyHound and Trailways would have changed, the old 2 strokes are 75 years old and still going strong   Took the EPA and the state of Ca to make the bus lines stop using the 2 stroke,  

A pitful sight when you see a new MCI 4500 at F/J filling up with natural gas I saw that at Baytown TX F/J at Thomson Rd on Friday could not believe my eyes I guess it's the future Pilot/FJ are spending tons of cash betting on it 100+ of their truck stops are supposed to have natural gas refilling stations by years end + another 100 by the end of 2014

[TomC]

Yes we have many natural gas buses running here including the MCI buses. The compressed natural gas tanks take up the rear most cargo compartment. I believe the capacity to be around 100gal diesel equivalent. Since there is currently only one engine approved for California, that would be the Cummins ISLg putting out a maximum of 320hp and 1,000lb/ft torque. The buses perform very well-that is when they are running. At Freightliner, we have many natural gas buses and trucks in the shop with blown engines. As usual, Cummins didn't do a complete job at converting the ISL Diesel to natural gas. The cast aluminum deep dish pistons (to lower compression) have a tendency to get holes punched in them, and just plainly melt down. The cylinder head gasket goes frequently. The main thing is the one piece exhaust manifold. Because of the high exhaust heat, as compared to the Diesel, the rear cylinder manifold cracks, then will take out the cylinder head also. Many times the turbo cracks also. Usually about a $7,000.00 repair bill.

Next Cummins is coming out with the ISX12g with power up to 400hp and 1450lb/ft torque-more suitable for truck use. Freightliner is designing this engine into the short hood Cascadia that can be a day cab, 48" mid top sleeper, 60" mid or high top sleeper, 72" mid or high top sleeper. With the sleepers there will be a 5 tank stack cabinet behind the cab plus two chassis mounted torpedo tanks. About a 180gal Diesel equivalent capacity. With the natural gas getting about 5mpg (compared to the Diesels getting 7-8mpg), the 90% usuable range will be about 800 miles. Enough for about a day and a half of single driver driving. The ISXg 12 will first be available only with the Allison 4000, then later with any of the manual or automated transmissions.

Personally-I'll stick with Diesels. There are still emissions on the natural gas that are not even regulated that Diesels don't produce. Good Luck, TomC

[bobofthenorth]

My apologies to the OP for contributing to the thread drift but roughly how long does it take to fill those 7 tanks Tom?  I have a little experience with handling compressed gas and I think the fuel industry is headed for a tankfull of trouble on this one.  Temperature compensation, metering problems, slow pumpiing issues - I'll stick with diesel too.

[luvrbus]

The 3 KW's I saw at Cole's dealership were 475 hp with 1750 ft lbs of torque 15L with just 2 side tanks they were Westport/Cummins they looked like a ISX to me and they were being delivered to FedX maybe no more overnight shipping lol

[belfert]

I had experience with some old airport tugs converted to natural gas.  I think they were originally gasoline powered, but not really sure.  They had six or eight tanks mounted behind the driver with a section of railroad track welded to the front to keep the wheels on the ground.  Anyhow, they took 10 to 15 minutes to fuel each time.  I have no idea if better equipment could reduce that time now.  The bad part is all those tanks still had less capacity than the original gas tank.  We could go a full day on gasoline, but maybe 2/3 day on natural gas.

The good news is no more engine problems after converting to natural gas.

I would love a natural gas powered car, if there was any place to fuel it.  Right now I am aware of one public CNG pump in the entire Minneapolis metro area.

[NonHippieBus]

This is a great natural gas thread now

[HB of CJ]

Didn't Trailways try out the air cooled 4 stroke V8 Deutz diesel for their mountain routes?  If memory serves, (always suspect!) the repowers failed to deliver enough power, or overheated, or failed to properly heat the interior, or all three or something like that.  HB of CJ (old coot)

[luvrbus]

We do drift   but to answer the question Eagles could have Man,M/B,Cat,Cummins or Detroit since the late 50's they even gave the Ford turbine engine a try in the 70's MCI offered different engines sometimes in 80's 

Buses were built for your 2 largest people mover Trailways and Greyhound I am sure if they wanted a different engine it would have happen as they controlled the market for the manufacturing   

[zubzub]

This is a great natural gas thread now

Basic question was answered by TomC first out of the gate after your question.

[wg4t50]

One important fact about our DDC engines, They are easy to start  and go to work, that has not been true with Cat nor Cummins 50 yrs ago. So they just became the standard.