(A) SIMPLE REPAIR OF A SEPARATED DRIVER:
       Old drive wheels frequently dry out, resulting in separation of the metal rim from the whitewall insulator. As a result of this, the metal rims can come in contact with the chassis. This in turn creates a short across the two rails. You cannot operate the engine this way without causing damage to the motor.
       Repair of this separation can usually be done quite simply, without having to pull the driver off the axle.
       (1) Remove all linkage from that side of the engine.
       (2) Clean all grease, dirt, and oil out of the "gap" between the rim and the whitewall, using a little tuner cleaner or rubbing alcohol on a tissue or pipe cleaner.
       (3) Apply a tiny amount of superglue in the gap and spread it evenly around the whitewall with a toothpick.
       (4) Carefully squeeze the two parts back together tightly. This is best done with two small screwdrivers placed under the rim, one on each side of the wheel. Be sure the whitewall is evenly and fully seated within the rim.
       (5) Replace all linkage.

(B) DRIVERS SLIPPING ON THEIR AXLES?
      If you have a drive-wheel which is loose and slipping on its axle, there are a couple of repair tips to attempt before you replace the entire wheel. If slippage is due to wear within the axle-hole, more-often-than-not, this can be corrected by removing the wheel, placing it flat on top of a vise, and firmly hitting the axle-hole with a ball peen hammer. Then flip the wheel over and do the same on the rear side. This will usually tighten up the hole enough that it will firmly grip the axle. As a second possibility, if you notice that the axle end has badly-worn splines, remove the axle and rap that with a hammer as well, reshaping the end of the axle slightly. If these don't solve the problem, you will need to replace either the wheel, the axle, or both.

(C) REBUILDING A DAMAGED DRIVER:
       In order to repair a damaged driver, it is necessary to pull the wheel off the axle and dis-assemble the three parts of the wheel.
     (1) Pull driver from ONE side only. 
    (2) Place driver upside down on top of an open 35mm film canister, and tap on the backside of the central hub. The canister is just the right size to support the rim and allow the hub to fall into the canister. 
    (3) Carefully remove the whitewall from the old rim. Hopefully, it will not break and you can re-use it. If it is damaged, they are replaceable.
     (4) Clean all parts of grease and oil. 
    (5) Reassemble the wheel in reverse order, using the new rim. First, test the whitewall for proper fit inside the outer rim. It should be snug.  If insertion of the whitewall into the rim is a difficult fit, use a piece of fine emery paper to sand the outer edge of the whitewall lip. (Actually, I use a sanding drum on my Dremel tool to do this easily.) Once you’ve created a snug fit, separate the two parts and spread a drop of superglue with a toothpick, and then press the two parts back together.

     (6) Note that the center hub is tapered, so you MUST insert the hub into the rim and whitewall from the FRONT, not from the rear. Once again, test for a snug fit, but do not use so much force that you snap the whitewall. Once again---if necessary--- sand the inside of the lip of the whitewall until you can insert the hub snugly. And again, spread a drop of superglue and re-assemble.                                                     

     (7) Mount the wheel on the axle, paying attention to necessary quartering. For most engines, this can be done adequately by "eyeballing" it. Northern and 0-8-0 engines can be a bit trickier to quarter correctly without the proper quartering tool. 
    (8) For easiest quartering, spin the motor so that the drivers on one side of the engine are all aligned with the linkage screw-holes at the bottom of the wheel rotation. Hold them firmly in place with your hand while carefully turning the engine over. The drivers on the opposite side should now be aligned with all the linkage screw-holes between 87 and 90-degrees off from the first side (i.e, either all at the forward point, or the rear point, in their rotation). 
    (9) Carefully place the loose driver on the axle, correctly positioned. Press it in place with your fingers. Then gently tap it on the rest of the way, with the opposite-side driver supported against something like the top of your vise. (A better option is the use of wheel cups to press the wheels, if you happen to have them.) 
    (10) Check proper wheel gauging when finished. (A simple wheel gauging tool is a dime ! A dime should just barely drop between the two wheels, with very little or no play between them.)
     (11) Attach linkage, and test for free rotation (no binding) before you totally re-assemble the engine.

Parts available for driver repairs include:

• Flanged rim, plain (specify 1.33", or 1.38" outside diameter)
• Flanged Pullmor rim, with vulcanized rubber tread (specify 1.33", or 1.38" outside diameter)
• Flanged Pullmor rim, with vulcanized rubber tread, for 0-8-0
• Flanged rim, 0-8-0, plain
• Non-flanged ("blind") rim, plain
• Non-flanged ("blind") rim 0-8-0, , plain
• Whitewall insulator, standard
• Whitewall insulator, "yellowed", standard
• Whitewall insulator, 0-8-0
• Replacement Pullmor bands, standard steam (adhere with superglue)
• Replacement Pullmor bands, Diesel, 0-6-0, & 0-8-0 (adhere with superglue)
• Replacement thick Pullmor bands, standard (for later grooved drivers)
• Replacement thick Pullmor bands, Diesel, 0-6-0, & 0-8-0 (for later grooved drivers)
• Hubs, standard steam (original; 0-8-0, or Northern, not included)