MK5000C questions

Jack was correct that the MK5000 was not a successful locomotive design. They were very expensive to manufacture and often had engine troubles and other mechanical failures. They also had an unusual cab design that most crews disliked.

Morrison Knudsen declared bankruptcy as a result of the MK5000C's unsuccessful run. Wabtec purchased the company and immediately ceased production of the MK5000C.

Only 6 were ever built. All 6 units are in service on the Utah Railway, and operate on former Southern Pacific lines. They have been re-powered with reliable EMD 16 cylinder 645 prime movers, replacing the trouble-prone 12 cylinder, 5000 hp Cat 3612 engine which was constantly plagued with various mechanical issues. 

I'm no MK5000C expert. I found all this with a 30-second Google search.

Rest assured...there ain't gonna be any Tier 4 MK5000s!

Rich, according to utahrails.net, all six MK50-3 engines had left Utah by April 6, 2017.  Probably all going to other GWI properties.

Larry

PSAP2010 posted:

Rich, according to utahrails.net, all six MK50-3 engines had left Utah by April 6, 2017.  Probably all going to other GWI properties.

 

Larry

I believe they're all going to the KYLE railroad in Kansas which is a G&W property. The KYLE also has Tunnel motors so they're collecting quite an eclectic group of engines 

2 what is an MK5000C'S  top speed both now and back then if it changed when they got fitted with new engines?

What diesel engine (prime mover) is in a locomotive has nothing to do with its top speed. I've run switch engines at 60mph. The top speed of a loco is usually governed by the max RPMs  the traction motors can stand without damage. I don't know the specs of the MK5000s but I'd guess their top speed is probably in the 70mph range. Though of course you have to be on a RR  that allows that speed and on track rated for that speed.

3 what is the coldest temperature an MK5000C can operate in?

Well I don't think these were some special southern USA only locos and it gets COLD in Utah so I'd expect them to operate down to minus 40 degrees F or they'd be kind of useless.