GP15-1 --> GP15-2

[MEC407]

It's nice to see these Baby Tunnel Motors being rebuilt with added functionality and improved reliability. And they're cute as a button!

Photo by Kevin Burkholder: http://www.railpictures.net/viewphoto.php?id=423206


Naturally, my thoughts immediately turned to "What if EMD built a V6 710?" At 1500 to 1600 HP, it would be the ideal replacement for the non-turbo 12-645 engines in these locomotives (or the turbo 8-645s in GP15Ts).

[RickRackstop]

EMD has been using the camshafts as counter balance shafts since 1938. This means that they have counter weights at each end on the camshafts that work with similar weights on the crankshaft. In going from 567 to 645 to 710 the piston keeps on getting heavier and on the rather commonplace conversion of 567 to use 645 power paks the heaver 645 counterweights have to be applied. The length of the engine is also a factor in that the counterweights for the 20 cylinder engines are the lightest and the 8 cylinder engines' are by far the heaviest. Their was a problem with the early 8 cylinder engine where the cam bracket would pull out taking a piece of the crankcase end sheet with it requiring the company welder to come out to repair it and add reinforcing blocks as well as newer wider cam-brackets that required plug welding the original threaded hole and drilling and tapping new ones. Later 8 cylinder blocks also have thicker end sheets but the repair described above has held up well in over 40 years of service.

As far as a 710 v6 is concerned I think that the counterweights would be too large. I personally would like them reintroduce the V8 and V12 645's to cover the low end of the horsepower range. They built power product 645's up until the end of GM ownership but dropped it because of poor sales. the EMD distributer in in California, Valley Diesel sells tier 2 kits for 645's including blower engines so it isn't that hard, after all both 645's and 710's use the same cylinder heads and therefore use the same EUI fuel injectors.

[MEC407]

Thanks for the information. Greatly appreciated. Does this imply that making a Tier 4 645 wouldn't really be any more difficult than making a Tier 4 710?

[RickRackstop]

Thanks for the information. Greatly appreciated. Does this imply that making a Tier 4 645 wouldn't really be any more difficult than making a Tier 4 710?

Probably not except for possibly turbo design which would add to the expense.

[MEC407]

Here is a video by "TNT314159" of the GP15-2 demo unit in action: http://www.youtube.com/watch?v=jqhUEvVrckc" onclick="window.open(this.href);return false;