Increasing the pulling power of an older Bachmann HO K4

[Penn1974]

I purchased an older Bachmann HO Spectrum K4 off of Ebay. The pulling power is not that good on a 2 1/2" grade. This is a DC engine. I think that I have to add weight to both the tender and engine. What would be the final ideal weight of the tender by itself? What would be the ideal weight for the loco itself? I have never disassembled a steam engine to add weight so I do not know where to begin. Is there a description paper that shows how to do it or a video that shows how to ad weight to the shell? Thank you in advance.

[HoModeler]

Why don't you just add another Steam Engine to the head end to pull the grade or a diesel should aid in pulling that 2% grade. That would be the simple fix. Instead of messing with a good working Loco already. & if you never did a motor swap out in a loco I suggest to in list in a friend or a hobby shop that can teach you or do it for you that has the experience & know how

[ebtnut]

I have had the same issue with an older K-4 - it was an effort for it to pull even three passenger cars up a similar grade.  It probabaly needs more weight, but I haven't had the time or motivation to open her up and see if there's room for any more. 

[Trainman203]

One place you can add weight to a steam engine, that surprised me the first time I heard about it, is under the cab roof inside the cab, down to the top of the windows.  Paint it black and you'll never see it.  

You ought to be able to do this without taking the engine apart .  You can use double stick tape temporarily to see how much you want to put in.

I'm far from being a  PRR fan , but everyone has seen pictures of doubleheaded PRR Pacifics on heavy passenger trains.