Upgrade or replace Spring-Belt Drives?

[Green_Elite_Cab]

I think the gearing is in the trucks, so I probably wouldn't fiddle with the ratio in the drive.

I've got a bunch of old Suydams and Walthers with the spring drive. Most haven't been run for years, so...

I keep neglecting to take pictures, but the gears in the trucks consist entirely of the gear mounted on each axle, which mesh with a worm gear mounted on a shaft driven by a pulley and the spring belts from the motor.

Last night I coaxed the model into running briefly, and this time with all the spring belts turning and no slipping I could detect, but it ran fairly slow.

The plan now is to replace these pulleys and spring belts with some sprockets. Fortunately, the pulleys are attached to the shafts by a little screw, so they should slide off easily.

The tricky part will be unsoldering the trucks (which consists of two sheets of folded brass fabricated into a box), so that I can gain access to the truck pulleys. I will also have to carefully remove on of the worm gears, but I imagine I can press these on and off, and use flywheel cement to reattach them if necessary.

I believe these sprockets have a smaller opening than the diameter of the shafts, but I should be able to open them up a little if I am careful, and still keep them snug on the shafts. Again, the loctite I used to affix flywheels will probably work here.

I purchased 4 small 8 tooth sprockets and 2 slightly larger 10 tooth ones, as well as a foot of chain. Hopefully they will arrive soon. so far as I've measured, they should all be able to fit. In fact, the diameter of the small sprocket over the chain is only slightly wider than the current spring belt system, and there is still plenty of room, relatively speaking.