Are the Tiers coming to a Diesel fleet near here ?

 
  GT46C-ACe Assistant Commissioner

Location: Sydney, NSW
EMDs of all flavours from about the GP7 onwards is a rebuild candidate to be fair.

EMD closed down local manufacture in an effort to reduce purchase price of Australian EMDs. Would guess the price per is something like the C44 now.

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  fzr560 Chief Train Controller

It seems at a glance that lots of the EMD family (in the US) from SD50 onwards is a potential rebuild candidate , and heaps of DC GEs , assumes Dash 9s .
NS is updating lots of locos and pleasingly those SD60s are getting or being rebuilt with Tier series EFI 710 16s rather than the wuzy 710 12 Eco .

Had that Tier 0 90 class been serious it would have grown later EM2000 computers , EFI and an electronic air brake system .
I believe the Yanks are claiming a 7% fuel consumption reduction but I think NS also add their own brand of split cooling as well .
I think the SD60 DC had a similar poverty pac 3800 Hp 710 16 as the 90s and upgraded they crank out 4000 odd .
A 90 could use a more serious alternator and traction motors and with electronic AB probably have the ECP fit out as well .
The 5000/5020s weigh more than 90s so an axle load increase may not be an issue .

Maybe not a cheap exercise but it would future proof the smallish fleet , make them potentially cleaner more reliable/economical and available to pull the ECP coal rakes . I can't see an export GT46ACE being cheaper landed here .
BDA
With PN's loss of the Mac Generation contract, the time for rebuild/withdrawal of the 90's maybe approaching. The 90's certainly appear vulnerable in their present form. I believe PN investigated extending their use further northwest but did not proceed. The inability to do a "straight swap" in the event of engine failure was an issue. Also axle load restrictions in Werris Creek yard meant they were not suitable for banking duties.
                I'm sure the TTs could find some useful work elsewhere if PN chose to rebuild.... On the short south perhaps.

                If, as you suggest the 710, alternator and traction motors all need upgrading, wouldn't it make sense to go to GT46ACE+ standards and in effect have a heavy heavy TT?
  BDA Chief Commissioner

Location: Sydney
Not impossible provided you could find space to fit the control system bits and inverters .
USDM units have a lot more physical space inside them than ours do .
The idea originally was to have common spares with 82s so same traction motors alternators and probably individual cylinder assemblies . The trouble is that the dinky alternator holds the power output back and the higher axle loads probably mean the traction motors can be loaded to the point of cooking without wheel slip limitations . I would have though they'd have thermal overload protection but maybe not .
50 and 60 series EMDs don't look so hot on paper and you had to get to 70 series before they got serious with alternators and traction motors .
  BDA Chief Commissioner

Location: Sydney
With a bit more reading it's obvious that some US operators have been or are rebuilding just about anything with 4000 odd horsepower preferably with split cooling .
The big issues with the EMDs seems to be cooling capacity EFI and Siemens electrical gear in the SD60/70/90MACs .
The Siemens inverters etc are drying up so the logical solution is to convert to the Mitsubishi parts like the SD70ACe series got .
The 60s and 70s don't seem to be getting the ACe sized cooling group but are stepping up to Tier 0 or 1 emissions standards .
Canadian built 90 classes look very much like a lightweight SD60 on paper .
I think the flurry of rebuilds/upgrades was driven by perceived fears of the Tier 4 units compliance issues and the possibility of them being more expensive to feed . I haven't read any reports on how the 70ACE T4 goes but someone will eventually post their opinions .
  M636C Minister for Railways

With a bit more reading it's obvious that some US operators have been or are rebuilding just about anything with 4000 odd horsepower preferably with split cooling .
The big issues with the EMDs seems to be cooling capacity EFI and Siemens electrical gear in the SD60/70/90MACs .
The Siemens inverters etc are drying up so the logical solution is to convert to the Mitsubishi parts like the SD70ACe series got .
The 60s and 70s don't seem to be getting the ACe sized cooling group but are stepping up to Tier 0 or 1 emissions standards .
Canadian built 90 classes look very much like a lightweight SD60 on paper .
I think the flurry of rebuilds/upgrades was driven by perceived fears of the Tier 4 units compliance issues and the possibility of them being more expensive to feed . I haven't read any reports on how the 70ACE T4 goes but someone will eventually post their opinions .
BDA
To address your last two posts:

The 90 class was limited to 3800 HP (like the SD60) by the capacity of the AR11 alternator, as you say.
At the time, this was probably not seen as a big problem.

I was assured that the electrical and electronic fit of the 90 class was the same as the SD70, although it kept the smaller alternator and the non-steering bogies of the SD60.

The traction motors were the same as the 82 class but with the entusiast