The front truck is different from stock. The truck you have on the front of yours is the tender truck from a Delton C-16. The railbus truck has a shorter wheelbase. It’s got coil spring detail molded in, whereas the C-16 truck does not. The wheels are probably a smaller diameter as well, but possibly the same, just closer together.
My suggestion would be to replace the front truck. If you can get a truck from one of Bachmann’s “20-foot” cars (the small ones with the 24mm wheels), that’d be my first thought. Otherwise, look for a junk Newbright car (sorry, that may be redundant), and use the trucks from that. You can still probably use the same 24mm Bachmann wheels, though you may have to do some minor surgery on the Newbright truck so the wheels fit.
On the motor block, presuming it runs and its only fault is a lack of a mounting pin, that’s easy to fabricate. I’d use a thin brass plate that I could screw to the top of the existing block with a short section of brass tube soldered to it for the pin. You could use styrene, but I just don’t trust the joint between a styrene tube and plate to be strong enough to take the abuse of being carried around.
If you want to power both axles, you could take off the side frames and use sprockets and chains a la Galloping Goose. Servo City sells sprockets and chains. Depending on the diameter of the axle, the sprockets may be a press fit onto the axles. Depending on how tight that press fit is, you may be able to get away without any kind of mechanical fastener to hold the sprockets in place, or you may want to drill through the sprocket and attach it to the wheel itself.
Here’s my scratchbuilt power truck showing how I’ve got the sprockets and chains. On mine, the wheels are spoked, so I only needed something to stick through the sprocket far enough to where they’d engage the spokes. Phil’s Narrow Gauge pins did the trick for me, but an 0-80 screw should work just as well. In the case of the Delton wheels, they’re solid, so you’d have to drill a hole into the wheel. The screw just has to engage the hole, it doesn’t necessarily have to be threaded. (The sprocket is soft enough to be self-tapping if you don’t have an 0-80 tap.) You don’t need but one screw into the wheel to transmit the power from the sprocket. You can do more for aesthetic reasons, but you can also cut them short so you don’t need to drill into the wheel.
Later,
K
