7900 series problems.

[Bridgeportbus]

Bus 8048 has just broken down. The engine just cut out at archer and pulaski. According to the driver this is not an unusual occurence. "First the low coolant light comes on then the engine shuts off" Has abybody else experienced this. If thats the case this may be a 7500 series repeat, especially since this bus is less than 6 months old

Edited July 14, 2015 by Bridgeportbus

[sw4400]

Bus 8048 has just broken down. The engine just cut out at archer and pulaski. According to the driver this is not an unusual occurence. "First the low coolant light comes on then the engine shuts off" Has abybody else experienced this. If thats the case this may be a 7500 series repeat, especially since this bus is less than 6 months old

I wouldn't put too much stock into this right now.... buses of today are very high tech, and have many computerized sensors. If that sensor goes bad, it'll tell the main computer that there is a non-existent issue and the computer will cut off the engine operations until the problem is checked via computer and rectified. Remember there were techs from Prevost at South Shops with all sorts of computer equipment and laptops for diagnostics. You could say these Cummins ISL9 engines are like little versions of "Hal".

 

[artthouwill]

Things happen.   Somehow it's possible that this bus was overlooked for fluid check.   My theory is that the bus was checked but someone left the bus in rear start mode.  The bus will only run so long before it shuts itself down in that mode.  BTW,  more often than not,  the lo coolant (on the old buses it was the hot engine) light will flash when the engine is shutting itself down. 

The other thing that happens is if the bus sits too long at low idling,  the bus will shut down.  Buses that sit at terminals or sit for driver reliefs should be on fast idle. 

[jajuan]

Yeah this is far from being another 7500 situation. The Nova LFS in both it's original configuration which the CTA got in the 6400s and the current Smart Bus configuration which they're now getting in the 7900s are proven models through their extensive uses in other TAs. If you want another 7500 situation you need a bus that failed the Altoona tests and which CTA acquired anyway because in part it was in dire need of new buses because of an entire bus fleet citywide being at or approaching retirement age. A lot of any bellyaching from an operator these days you really need to take with a grain of salt because of the reasons sw4400 and Art gave in addition to a lot of these operators being old timers who've grown comfortable with certain bus models and how they handle and thus resistant to change whenever a newer bus model is getting delivered. These same gripes and complaints were given when the 1000s and subsequent models thereafter were in the new and delivery stage of their service lives. The one exception would probably be the 500s. Those really were crappy buses.

[garmon757]

I didn't know our Novas were articulated! (Sarcasm)

[Busjack]

I didn't know our Novas were articulated! (Sarcasm)

MTA's and SEPTA's are, but I figure that with the enhanced inspection after the NABI debacle, including that the second payment isn't made until the bus passes CTA's inspector, at is probably correct relating to this stall.

[BusHunter]

Some of the Fg #6400's still have pretty good AC, better than I've seen on any #7900. I personally think the #6400's were a better bus when new than these #7900's. Ordering the #7900's without making the rear of the bus have optional opening hopper windows or even sliding ones might be a mistake that comes back to haunt them in a few years. While the #7900's might be a good bus, decisions on who is making the add on components, like the AC, will change the overall likability of the bus. That's where the error seems here. I think the #1000's are still a better bus and they are 8 years old. No wonder they are hoarding them away from Fg!! If you ask any operator today what's the best bus at CTA, I bet #1000's is the answer.

[garmon757]

Some of the Fg #6400's still have pretty good AC, better than I've seen on any #7900. I personally think the #6400's were a better bus when new than these #7900's. Ordering the #7900's without making the rear of the bus have optional opening hopper windows or even sliding ones might be a mistake that comes back to haunt them in a few years. While the #7900's might be a good bus, decisions on who is making the add on components, like the AC, will change the overall likability of the bus. That's where the error seems here. I think the #1000's are still a better bus and they are 8 years old. No wonder they are hoarding them away from Fg!! If you ask any operator today what's the best bus at CTA, I bet #1000's is the answer.

I had a few operators I talk to told me that they rather drive the 6000s than the 7900s, most because of the space and better AC.

[Busjack]

... While the #7900's might be a good bus, decisions on who is making the add on components, like the AC, will change the overall likability of the bus....

I thought everyone used Thermo King. At least Nova Bus still does (spec sheet). Must be one of the arcane things Andre mentions about how it is set up so the driver can't set the temperature to 68°.

[BusHunter]

I remember the #1000's were just the opposite, the freezerinos!! I'd see many operators with towels and things over their legs because the AC never shut off. They seem to fix that though after they delivered the first bunch to Archer. I don't know what it is with the #7900's but the AC is really weak. It's almost like it's not on. On a real hot day like this weekend, I wonder how warm they are, because when temps are in the mid 80's it starts getting uncomfortable on these buses. In that respect I'm glad I still have #6400's to ride cause they are way cooler.

[NewFlyerMCI]

I remember the #1000's were just the opposite, the freezerinos!! I'd see many operators with towels and things over their legs because the AC never shut off. They seem to fix that though after they delivered the first bunch to Archer. I don't know what it is with the #7900's but the AC is really weak. It's almost like it's not on. On a real hot day like this weekend, I wonder how warm they are, because when temps are in the mid 80's it starts getting uncomfortable on these buses. In that respect I'm glad I still have #6400's to ride cause they are way cooler.

#6400's AC's only worked in the wintertime when I rode them (when they shouldn't be on) and half the time it was because it was cold outside. The 7900's on the other hand are real good with the heating and AC. I haven't experience one on when it shouldn't be.

[BusHunter]

#6400's AC's only worked in the wintertime when I rode them (when they shouldn't be on) and half the time it was because it was cold outside. The 7900's on the other hand are real good with the heating and AC. I haven't experience one on when it shouldn't be.

Fg's #6400's are good as far as ventilation. I mean they'll surprise you with the buses like #6441 was actually cold and that's one of the oldest #6400's there is. There is #6629 that blows heat, but it rarely runs. i only saw it once in the last month. I haven't really been on the #7900's lately, maybe things have changed with the AC. I just don't like how they did the ventilation on the smart buses. With the ad racks pushed up to hang horizontally on the left side the vents are mostly facing the right side. i notice a big difference in temp in left versus right side riding. Now the heating on the #7900's is good because alot of the vents are coming from the floor versus the ceiling.

[jajuan]

I think the big issue with the 7900s that really makes it seem like the AC is weak, or exacerbates the problem is that the engines' exhaust heat seems to cycle inside the bus somehow. Sit on those rear seats over the engines on some of them and it feels like you're sitting in and on top of an oven. Sit in any of the seats forward of those and you do feel the AC with you feeling more of it the further forward in the bus you sit.

[Busjack]

I think the big issue with the 7900s that really makes it seem like the AC is weak, or exacerbates the problem is that the engines' exhaust heat seems to cycle inside the bus somehow. Sit on those rear seats over the engines on some of them and it feels like you're sitting in and on top of an oven. Sit in any of the seats forward of those and you do feel the AC with you feeling more of it the further forward in the bus you sit.

Sounds like a combination of their being similar to a 1950s bus with the rear seat being hot because it is directly over the engine (not recirculating the heat, but maybe inadequate insulation) and not having the big vent in the back like most buses that don't have back windows do. But maybe there is some recirculation because the engine cooling vent is above the window. I wonder if a diesel Xcelsior is any better.

Another difference compared to the 6400s was that the rear seat was not over the engine.

[andrethebusman]

Recently have been hearing 7900's are becoming notorious for "check engine" lights, and shutting down. After a few minutes will restart, but later that day or a couple of days later does it again, and so far cause has not been ID'd. Also, talk is that PACE 6440-6470's have a problem that was corrected by builder on 6480's and up, but needs to be dealt with before these can enter service.

[sw4400]

Recently have been hearing 7900's are becoming notorious for "check engine" lights, and shutting down. After a few minutes will restart, but later that day or a couple of days later does it again, and so far cause has not been ID'd. Also, talk is that PACE 6440-6470's have a problem that was corrected by builder on 6480's and up, but needs to be dealt with before these can enter service.

Again, this all goes back to sensors that are malfunctioning, making the computer think there is a non-existent issue with the bus, causing it to run improperly or shut down. In for example 10 of the 7900-series buses having this issue, 2-3 have a actual malfunctioning component causing the problem and the other 7-8 are just malfunctioning sensors causing a non-existent problem to show up and tell the computer to shut down part or all of the bus.

[See Tea Eh]

Recently have been hearing 7900's are becoming notorious for "check engine" lights, and shutting down. After a few minutes will restart, but later that day or a couple of days later does it again, and so far cause has not been ID'd. Also, talk is that PACE 6440-6470's have a problem that was corrected by builder on 6480's and up, but needs to be dealt with before these can enter service.

Victoria, BC, recently took delivery of new Nova buses this year and have had the same problem.  Lots of breakdowns due to check engine light issues.

[sw4400]

Victoria, BC, recently took delivery of new Nova buses this year and have had the same problem.  Lots of breakdowns due to check engine light issues.

It's pretty much a sensor thinking there's a non-existent problem. This is what causes 90% of the "Check Engine" lights. Engines are pretty much computerized now(note the Prevost techs at South Shops with laptops. Even the CTA mechanics got a course in computerized diagnostics for the Novas). Sometimes sensors go on the blink and create these non-existent issues.... look here at the problem with 2489-2490 that briman reported on

2490 got a bit tired and had to be retired early  It kept acting like it had hit a track trip, and eventually the driver had to keep it in ATC bypass to get it to move at all. It didn't make another run once it got back to Howard after that...

Maybe there was a legitimate problem with the railcar, but more likely than not, this was the result of a faulty sensor causing it to act like it hit a track trip and would not allow it to move unless it was in ATC bypass.

Sensors can literately stop a vehicle in it's tracks with no actual problem with the vehicle.

[See Tea Eh]

I'm well aware of the level of computerization of modern buses, but I'm not sure what a defect with a 30+ year-old railcar (or however old it was at the time it happened) has to do with the topic at hand.

[sw4400]

I'm well aware of the level of computerization of modern buses, but I'm not sure what a defect with a 30+ year-old railcar (or however old it was at the time it happened) has to do with the topic at hand.

Both are caused by the same problem.... a sensor that has paralyzed a vehicle, that's why I tied them together here.... regardless the vehicle, sensors can cripple a vehicle or a bunch of vehicles(in the case of what you said about Vancouver's Novas) if they suddenly start behaving erratically. Once diagnosed by a mechanic using computer technology, the faulty sensor can be reset and the vehicle will operate normally/be replaced with a new sensor and the vehicle will operate normally.

 

[Busjack]

1 hour ago, Shannoncvpi said:

The crooked goverment want diesels out & yea it good structural mechanics to down the nabis but at the same time when you go cheap thats when you have more problems like they have with the novas now always breaking down if you say your going to have a reliable fleet you have to spend that money not cheap out 

Since I assume your comment was directed to this topic....

It still isn't a question of "cheap out,"  but federal requirements. Buying a bus from anyone is about $575,000. Federal regulations say the TAs have to take bids. If these buses are that bad, CTA should have disqualified Nova Bus from bidding. They did not.

You seem to think that transit authorities just go to Napleton New Flyer, Bob ROHRMAN Gillig, Mancari Nova, and Bob Loquiercio ENC and buy buses. Even though paratransits are sold by dealers, the dealers still have to bid. Pace's 22000 series of paratransits come from Shepard Brothers Ford of Canandaigua NY.

[Shannoncvpi]

10 hours ago, Busjack said:

Since I assume your comment was directed to this topic....

It still isn't a question of "cheap out,"  but federal requirements. Buying a bus from anyone is about $575,000. Federal regulations say the TAs have to take bids. If these buses are that bad, CTA should have disqualified Nova Bus from bidding. They did not.

You seem to think that transit authorities just go to Napleton New Flyer, Bob ROHRMAN Gillig, Mancari Nova, and Bob Loquiercio ENC and buy buses. Even though paratransits are sold by dealers, the dealers still have to bid. Pace's 22000 series of paratransits come from Shepard Brothers Ford of Canandaigua NY.

I'm just saying when you go the cheaper way that what you get

[artthouwill]

1 hour ago, Shannoncvpi said:

I'm just saying when you go the cheaper way that what you get

To @Busjack's point outside of a disqualification,  the TAs are required to go with the lowest bidder.  The most recent example is the bid ENC recently won with Pace.  New Flyer's bid came in a few hundred dollars higher than ENC, but ENC was literally the lowest so they got the contract.  If this were a grant or some other source of funding not from the federal government,  TAs could purchase from whoever they wanted subject to rules, guidelines, and stipulations according to the funding source.  Even then, they might be subject to bids and taking the lowest bidder.

[Busjack]

11 hours ago, Shannoncvpi said:

I'm just saying when you go the cheaper way that what you get

So, given what @artthouwill and I said, what's your solution? Buy only Mercedes Benz buses, even though they are not qualified to sell in the US? Buy Volvo, even though they own Prevost/NovaBus? Import something from China (nobody likes BYD)?

Unless you have some solution other than the constant bus drivers' lament "[name of any bus] is junk," that's what you get with cheap talk. I also don't hear you saying anything about CTA maintenance practices.

 

 

?

[YoungBusLover]

2 hours ago, Busjack said:

So, given what @artthouwill and I said, what's your solution? Buy only Mercedes Benz buses, even though they are not qualified to sell in the US? Buy Volvo, even though they own Prevost/NovaBus? Import something from China (nobody likes BYD)?

Unless you have some solution other than the constant bus drivers' lament "[name of any bus] is junk," that's what you get with cheap talk. I also don't hear you saying anything about CTA maintenance practices.

 

 

?

I'll just add my two cents to bring everything back full circle. The solution is simple as far as Nova is concerned and that is maintenance has to do a better job overall with the lower series of #7900s and #8000s. You'd hardly see buses from Chicago and FG down at SS and there is good reason for that. Also operators have to do a better job at reporting defects better because I've had several #7900s in recent months with the same defects that I wrote tickets on not getting tended to. I try my best to avoid #7900s all together because of the headache they give me. Usually the main defects are Overheating Exhaust, Broken overhead compartments and sometimes rusted out compartments, loose shields/latches that hold them in place, rear seats not being properly secured, the braking system, the suspension, broken shocks and the front overhang is just the tip of the iceberg with the beating it takes on the daily. Lastly, The city has to improve its infrastructure overall. No bus manufacture of any kind can survive on rough terrain while also being improperly maintained but I digress though. Shoutout to SS though they're doing the best they can, I don't want to make it seem like it's all on them because we the operators play a key role at getting stuff fixed around here.