• A few B39s will be leaving

  • Discussion of present-day CM&Q operations, as well as discussion of predecessors Montreal, Maine & Atlantic Railway (MMA) and Bangor & Aroostook Railroad (BAR).
Discussion of present-day CM&Q operations, as well as discussion of predecessors Montreal, Maine & Atlantic Railway (MMA) and Bangor & Aroostook Railroad (BAR).

Moderator: MEC407

  by Realityrail
Add to that the reduction in fuel usage too. The B23's burn less fuel than the B39's. Also, horsepower = speed. With the track speeds at MMA, the B39's horsepower railiy comes into play. Tractive effort is a function of weight on drivers, and comparing the B39 to the B23:

B39-8 B23-7
Weight 280,000 # 260,000 #
Starting Tractive
effort 70,000 # 63,250 #
Continuius Tractive
effort 68,100 # 61,000 #

So while the B23's will pull less tonage, they will make up the loss in the fuel savings. One other kicker is the elimination of the "Dash *" electronics. The three cabinet boxes in the B39's are the CAB, AUX and EXE. When one of those becomes defective, 90% of the time they are returned for repair to GE at a cost of well over $8000.

  by Tom Tancula

Time to clear the air on the B23 "debate". While I have been viewing these posts for years, I have now joined the list as a member to express my position.

Our enthusiast community has a great network of information. I was surprised to see the news that the B23's were sold to MMA on this page, as it came very promptly after the purchase.

As for the current debate, both of the debating parties, neither of which I know or have met, have good information. Let me set out the facts:

The B23-7 units are excellent units. I inspected and specified these units personally. The condition of these units is a product of their maintenance at BNSF and GE.

Are they clunkers? No

Were they stored a long time? No. Here are the boring details:

#4207-Tie up date-3/24/07, rebuild date-1/97
#4224-Tie up date-3/28/07, rebuild date-03/96
#4231-Tie up date-3/22/07, rebuild date-05/96
#4237-Tie up date-3/24/07, rebuild date-09/97
#4243-Tie up date-2/23/07, rebuild date-08/97
#4252-Tie up date-3/30/07, rebuild date-01/98

Defects on these units are the radiator cabinet lower sheet metal corrosion, a leaking roof on one, plugged sanders on another. Four of the six were removed from service with no defects.

Fuel savings and tractive effort figures are correct, as is the notations above concerning door replacement, plows and ditch lights (and in particular the timing). I agree that top management dictated doing all of this work before releasing the units into service.

So as Charles Hastings said, let it go or take it off line. I would rather read opinions and news here than to watch a war of words.


  by Tom Tancula
One additional item. The B39-8 units that have been targeted for sale are 8522, 8536, 8539, 8546 and 8560. So get your MMA photos of these now, before they are gone.

And how does one use spell checker on this????!!!!


  by MEC407
Mr. Tancula, thank you very much for taking the time to join our site and for your willingness to share some information with us. Greatly appreciated.

Unfortunately, the site does not feature a built-in spell checker. :wink:

  by emd_16645
I stand corrected. Thank you for the information Mr. Tancula.

  by ShortlinesUSA

Thank for posting the excellent information. Any chance the B23-7s will get some sort of MMA markings prior to being placed in service, along the lines of the nose logo on MMA 3000? That little addition makes a sharp looking unit!

Hopefully these units will provide several years of good service for the MMA.

  by Tom Tancula

I know that the staff at Derby is trying to figure out how to do that, particularly on the units with the modern BNSF paint job. I trust that something as pleasing to the eye as the 3000 will emerge.


  by obienick
What happened to the former CDAC F40Ms?

  by Tom Tancula
They were scattered to the winds. These units were originally owned by Amtrak and leased to Iron Roads. Rail World Locomotive Leasing acquired the units before the formation of the MMA.

The units have been sold off to among others, the San Luis & Rio Grande, Iowa Northern (after being leased to a Canadian Railroad), and Titan Locomotive Leasing.

I recall that there are three units on the MMA. One is a shell belonging to the San Luis & Rio Grande, the other two intact and stored. Plans are to use the components of the two intact locomotives (owned by Rail World Locomotive Leasing) for the M62M rebuilding program in Poland.


  by emd_16645
The units going to the Iowa Northern were supposed to go to the Huron Central for a few months, but I never heard of them leaving. Are they still at Derby, or have they slipped out over the summer?

  by Tom Tancula
The left and are at the Huron Central.


  by MEC407
Mr. Tancula, has it been your experience (and/or MMA's experience) that the Dash 7 units are more reliable or less reliable than the Dash 8 units? Or are they about the same? I've heard conflicting stories from folks who operate them on the road as well as folks who service them in the shop.

Also, in regards to the "microprocessor" upgrades that were installed in #3000, how similar or how different is that system compared to what you'd find in a stock Dash 8 unit?

  by emd_16645
One complaint that I've heard about the dash-8s is that the bolts that hold the traction motors have significant problems. Operation over the jointed rail causes extra stress on these bolts, which from what I've been told by a crew they have to be replaced every 90 day inspection. Although this sounds minor (and it is), and extra maintenance that is needed is a headache.

  by Tom Tancula
Momma Mia! What a question!

I went back into my statistics to check the mean time between failure rates (MTBF). This shows the number of days between unscheduled shoppings and excludes planned maintenance and the traction motor bolt problems (more on that below).

In rank order from best to not the best, the performance is

#1 C30-7 Series 3600
#2 B39-8
#3 C30-7 Series 5000

I excluded the GP units and the lone B23-7 from the figures.

Now, comparing the C30-7 units to the B39-8 units, let’s look and the differences and similarities, from cab to radiators.

Control Cab
-Same air brakes and controls on both

Electrical Control Cabinet
-C30-7 units have relays and solid state “dash 7” controls, few engine sensors
-B39-8 units have three computers: CAB, AUX and EXE, plus several engine sensors

The B39-8 computers can cause a failure with only a minor glitch (a technical term!). These can be sent to GE for repairs which can cost over $5000 each, but some small defects have been repaired by MMA’s own staff at the cost of a few dollars.

Compared to the 3000, the system in that unit is better than the system in the B39-8 units. This is a mater of improvements as technology becomes better. To compare and contrast what Randy Stahl has shown me, the advantage over the B39-8 system is that it can be fine tuned in several areas of performance using a lap top computer to adjust among other function, locomotive adhesion.

If I had unlimited funds, my personal preference would be to install GE Bright Star on all of the units. We used this system on the GE fleet in Estonia and they pulled anything we put behind them.

Alternators and Engines
-C30-7 units have 16 cylinder 7FDL engines, rated at 3000 horsepower with GTA 11 alternators
-B39-8 units have 16 cylinder 7FDL engines, rated at 3900 horsepower (the staff at Derby reprogrammed the computers to reduce the horsepower for better fuel economy) and as I recall GMG 186A1 alternators

Reliability and rated performance is equal between the models

Radiator Cabinets
The radiator systems are very similar between the two models. GE operates as a dry system as compared to the EMD wet system. The GE units have no water in the radiators until there is a need to cool the water. At that point, GE uses a water diverter to send the water to the radiators. Once cooled, the water is diverted out of the radiators. This is why the GE units have no radiator shutters and similar vintage EMD models do.
With the GE dry system, clogged radiators can retain water even after the cooling water is diverted away from the radiators. This pooling of water can freeze in cold weather, causing winter radiator leakage. MMA has been diligent in cleaning their radiator interiors to prevent this.

-C30-7 units have engine (shaft) driven air compressors and engine (shaft) driven cooling fans – The compressors run fine, but MMA has had a few failures on the right angle drive mechanism for the cooling fan. The Derby staff has rebuilt more than a few of these.
-B39-8 units have electric (motor) driven air compressors and electric (motor) driven cooling fans – The compressor control contactors allow for two speeds, and these have on occasion failed, causing the motor and compressor to operate continuously, with the end result being a compressor motor failure. This requires sending out the motor for repair, and I know MMA has had a significant number of this type of failure. I do not recall any significant number of radiator cooling fan motors.

Traction Motors
The C30-7 units came with a mixture of GE 752E8 and 752AF traction motors. The B39-8 units came with GE 752AG traction motors.

The 752AG has a lighter frame than the 752AF. This causes traction motor case flexing and can cause open circuits and grounds in the field coils. Long ago, MMA made the decision to standardize on the 752AF as much as is possible.

As for the broken traction motor bolts, this has occurred between both of the models of locomotives. The bolts that are used to secure the traction motor gear case to the traction motor are what fail. This is caused by rough track. These failures occur during the winter freeze of the track structure. The section crews are working hard to eliminate the poor track so as to eliminate these failures. MMA was told by the NBSR that they too have the same problem on their EMD units and that they reduce track speeds in the winter to reduce these types of failures.

Interestingly enough, we had poor track issues in Estonia. But the GE’s there damaged the traction motor armature bearings and not the gear case bolts. The solution in Estonia was to replace the traction motor armature roller bearing, using a bearing with a one piece roller cage as compared to he original two piece cage. MMA 5017 has a specially designed Timken bearing on her #5 traction motor for testing. Derby Shop Manager Steve Johnston had the staff paint this motor orange to differentiate it as a test motor.

Now, after that long winded answer, you can draw your own conclusions. The facts are that these are good units, and the crew at Derby does a good job of keeping them running. As an example, the daily availability of the fleet on average has been increasing month to month this year.


  by MEC407
Thank you very, very much for taking the time to answer my questions!