I took the plunge.... Now I have questions

[Aviator]

So after spending way to much time here  I went out and picked up a 1992 MCI 102C3. It was run by a charter company and my retired "   'hound  " maintenance father gave it his blessing so....  Now its my project. 

(somehow I blame all of you for this affliction)

Anyway  I was looking at the cruising speed thread and was surprised at how fast you guys were talking about.

My 102 has a Cummins L-10 (it was re-engined about 190,000 ago) and a 740

With my foot on the floor 63 is all she's got and it will roll up to 65 down hill.  Tach shows 2800 RPM however I'm not sure I really believe it. Tach says idle is 800 and fast idle is 1200 which seems a bit high.

The Cummins manual says 2300 is the RPM at the top end.    I'm pretty sure the speedo is right judging from traffic and my dad pacing the bus as we drove it home.

Thoughts and of course here'e the mandatory pic after we took off all of the company logos (those 3M Strip Off wheels work wonders)

Larry

[wg4t50]

Sure sounds like a poor rear ratio, maybe it had an overdrive 6 speed Allison, not the 740 series.  The L10 has a good rep. in trucks.

[Jeremy]

My bus also came straight out of service with an operator and was (and still is) fitted with a speed limiter - perhaps yours is too?

Jeremy

[chessie4905]

   Welcome to the forum. First verify the accuracy of the tach. Someone with a handheld unit should be able to check it. Check with a hd truck repair place. Use a gps to verify speedo accuracy. Then we can go from there for what your options are. We'll need your tire size btw.You are sure it has a 740?

[Aviator]

I'm not 100% sure it has a 740,  I know its an Allison. I took a quick look at the trans electronic box. It's located in roof of bay 3 drivers side behind a door to the system tunnel. Can you identify the transmission by the electronics box?

I'm really certain the Speedo is right on. matches my car spot on.

I can tell that the bus came from the factory with a Manual and a clutch.  I can see the steel plates they put on the floor to cover the holes and I can see the remaining clutch linkages when you open the service compartment on the drivers side. Plus the shift pattern plates is still next to the drivers seat

Thanks Guys

Larry

[chessie4905]

   Here is info from one of their manuals. maybe that can be some help.  I don't know what you can see on an MCI without having to block it securely to get under it.http://igor.chudov.com/manuals/M939-Series-Trucks/Allison-MT-654CR-Transmission/Allison-AT-MT-HT-Transmission-Operators-Manual.pdf

   Otherwise that rpm/speed works out to approx 5:50 ratio rearend......sounds like trans is not running in high or 4th. Maybe only going to third gear?

[B_K]

OK first off a 740 is not going to have a "trans electronic box"

So that means you have a.........

Could be a 748 or who knows.

Since it's been converted to an auto from a manual all bets are off.

Best thing for you to do is contact the company you bought it from and speak to the "shop foreman" an ask him what he can tell you about it.

Where are you located? What company used to own the bus?
  BK 

[Aviator]

BK
I'm in Northern Indiana.

The bus came from Star of Indiana (they're owned by Free Enterprise) and was based in Indianapolis. They bought the bus 5 years ago and it has been changed before they got it.

Well about the electronic box.  I'm not near the bus, but the electronic box I found says Allison on it so I assumed it for the trans. I'll shoot a picture

The shift selector has buttons for R N D  and if i remember right 1 2 3     There are no arrow push buttons and no LED  I do not have a transmission Check light (at least nothing on the dash or the pad that i have seen and no other buttons that seem to be related to the trans. My dad is at a loss here because the Hounds we never converted to Auto if the came with a manual, Greyhound stopped buying manuals as soon as they could and sold the manual fleet when it timed out and that was back in the MC-7 days

When I drive the coach, It starts moving easily in first and it runs to 25 on the tach and shifts but the tach only drops to 20 and then it feels like another shift (but that could be lockup) at 25 on the tach, another shift (approx 30 ish-MPH  then back to 25 on the tach and another shift (40-ish Mph) then it just winds on out to 62 with my foot on the floor. There maybe another lockup in third, I haven't driven it in a week.

I know the Cummins L-10 is a mechanical engine. No electronics to be found

So  Any thoughts on how I figure out what transmission is in this ?  The guys at Star thought is was a 740 but they could have been mistaken.

Larry

[Aviator]

Found this online   This is what my shift pad looks like

Larry

[chessie4905]

   Try to get the info off the plate on the case just above where the pan attaches to the case on the right? side. It should have the model and serial number. Hopefully it is still attached. The serial number can be given to any Allison Trans dealer to determine the model number if it is not on the tag also.

[busguy01]

Trans could also be a 741 which is the electronic version of the 740. It does have a allison box(ATEC). Hope that helps. Does sound like it is not shifting into 4th gear. Should happen at about 55 mph
JimH

[luvrbus]

You have a shift pad or shifter tower is the engine is electronic or manual there were a lot of the L-10 E that had the B400 behind it you could have a 741,746,747 ,748 or the B series if a electronic transmission 

On the drivers side above the transmission oil  pan about the middle of the transmission is a tag that will tell you what transmission is there keep your fingers crossed it doesn't say 741 

good lucky

[B_K]

Trans could also be a 741 which is the electronic version of the 740. It does have a allison box(ATEC). Hope that helps. Does sound like it is not shifting into 4th gear. Should happen at about 55 mph
JimH

You have a shift pad or shifter tower is the engine is electronic or manual there were a lot of the L-10 E that had the B400 behind it you could have a 741,746,747 ,748 or the B series if a electronic transmission 

On the drivers side above the transmission oil  pan about the middle of the transmission is a tag that will tell you what transmission is there keep your fingers crossed it doesn't say 741 

good lucky

OK there ya go Jim, Clifford & chessie4905 have told you pretty much what ya need to know.

Yes the "Allison box you found will be for the trans.
Now ya just have to figure out which Allison.

An yes I'm familiar with "Sodrel's" Free Enterprise & Star of America (and trucking co) operations.
Even if it was converted before they bought it, they should know what transmission it has. (they did service it didn't they? hard to buy the right filters, & parts without knowing what it is!)

BTW the Hound did still have some manual transmissions up into the mid '80's.
I know this because my uncle used to own a '84 "9" and a '85 "102A3" that both had been hounds and still had 4 spds in them. 
  BK 

[luvrbus]

That is a generation 1 shift pad it should have a do not shift light next to the N on the pad it's not for the world transmission so you probably have the 700 series

[Aviator]

Thanks gentlemen!

As soon as I get back in town I'll get dirty and find the data plate

Thanks

Larry


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