Replacement (or improvement) for Intermountain N SD45-2 drive

Model Railroader General Discussion (Model Railroader)
1

Hi all,

I have an Intermountain N scale SD45-2 locomotive that I’m currently running as the primary power for my small N scale layout. I know IM’s N scale loco reputation is not the best, but they happened to produce a model of HATX leasing #914, which ran on the Cape Breton and Central Nova Scotia (CBNS) Railway for several years. The CBNS is the setting of this layout, so it fit the bill.

The locomotive is an okay runner, but its pulling power is, well…non-existent. I found it could easily be outpulled (at least double) by a Kato P42 I had sitting around. Of course a P42 won’t do in shortline freight service, so I am looking for a fix.

I have two questions:

  1. Does anyone know of ways to improve the Intermountain drive? I know it’s awfully light and I need to add some more weight, but anyone have any other suggestions?

  2. What would be a workable replacement for the drive? Does anyone know, for example, if an IM SD45-2 shell would fit on a Kato SD45 drive? Or perhaps an SD40-2? What about an Atlas SD50?

Any feedback would be much appreciated. Like I said, the locomotive is functional, but it is a long way from what I’d like in terms of pulling power and smooth performance.

2

Bull frog snot. Nothing wrong with the IM drive … It is state of the art. The reason your P42 out pulls a hooded loco in N Scale should be obvious; amount of weight in the frame. Swapping your drive for a Kato one won’t make any difference. Snot will. David B

3

Thanks for the suggestions David. I’ve heard good stuff about that Bullfrog snot in the past, so maybe I should see about getting some (assuming that doesn’t involve catching frogs and extracting it :wink: )

The weight issue is certainly something I recognized. I think there’s some space left in that IM to pack a bit in, if I’m creative about it.

The other thing though, besides lack of pulling power, is that the Intermountain is oddly jerky at times (it’s quite subtle, almost in a pulsating sort of way, just enough that the slack in the cars behind it bounce noticeably). This isn’t an issue of dirty wheels or contact problems (checked that all through, no issues), and it seems to be a bigger issue in one direction than the other. The unit is well lubricated too, so I’m not really clear on what’s responsible for the strange performance.

I haven’t made any decision on what to do with it yet, just thought I’d put these questions out to see what sort of options I might have.