Loose Drive Gear on Diesel Motor

Tom-

Yes, this can definitely be repaired. The gear in question is the motor gear (Lionel part #2333 M-14), which most postwar part dealers (East Coast Train Parts, Olsen's, The Train Tender, etc.) have in stock for a few dollars.

The motor gear is pressed onto the armature shaft, but you should be able to remove it easily (especially since the existing gear is loose). You will notice splines on the armature shaft (little ridges running parallel to the shaft), which hold the gear by means of an interference fit. To install the new gear simply push it up the shaft until the splines engage the inner diameter of the gear. To ensure the new gear is installed perpendicular to the shaft, you might need a gear puller or similar tool to ensure a good fit.

Since you will have the motor apart, it is an ideal time to look at the other idler gear, brushes, commutator, and miscellaneous bearings to ensure all these parts are in good condition too to ensure maximum motor performance. You can also refer to this drawing www.olsenstoy.com/cd/locos%5Cloc2333f.pdf from the original Lionel repair manual for more information about the additional parts. Just like the gear, these are all common parts and most postwar part dealers will have these in stock for a nominal cost.

Good luck!

-John

John:  Thanks for your help.  I believe all the debris I found around these gears was not only from the loose gear, but the splines on the motor shaft, which I have confirmed have been worn smooth.  This being the case, I assume either I replace the armature with one that has the splines intact on the motor shaft, or retire this motor. Do you agree?

Tom

You could try using nipper pliers and carefully re-add splines/deformation to engage a new gear.  I would also use a locktite liquid prior to pressing it on.  Not much to lose.  G

The Lionel service manual discusses your problem on this page.

Another idea (may be do both):

How loose is the gear on the shaft?
If these isn't much play, you might be able to use a drop of locktite to bond the gear to the shaft. You would have to carefully clean away any grease, oil etc. And be careful not to get any locktite anywhere else, such as the bearing.

Finally, be aware that Madison Hardware (Detroit) had a sale on bulk lots of assorted armatures. Some were good, some were defective.

Among the armatures I received were 2333 armatures that were bent right where the spline was machined into the shaft. (There were also 364 armatures that were bent right at the machined tip)
Many people had these armatures for sale shortly afterwards.

I don't know how useable they are.

If anybody has recommendations on how to straighten the bends, I'd appreciate reading about it.

CW, Isn't that what I said?  Use nippers and Locktite?  G

Thank you GGG and C. W. for your additional advice.  The existing drive gear bore is significantly larger than the armature shaft diameter.  So I think I will purchase a replacement drive gear, and see if I can mechanically re-introduce some spline grooves onto the shaft, and install the new gear with some loctite. 

Thanks again for your help.

Tom

You will achieve better performance by replacing the shaft.  I have successfully converted single shaft Canon motors to double shaft (NWSL shaft material) using a slightly modified process (no press) described here.

Some tips and photos from a fellow modeler at the Sacramento Model Railroad Historical Society:

The shaft in the Canon single shaft motor is serrated and must be pressed out and a new shaft pressed in.  This requires that you construct jig to keep from crushing the motor wires.  I have attached three pictures of the jig and pressing process.  You will need a heavy press like the PanaPress.  My first jig was made with brass tubing.  Later I had a friend that made one out of stainless steel.  The nylon spacer you remove from the motor will give you a guide for the tube material.  Be absolutely certain that the tube in the jig is against the steel motor core and is not pinching any of the wires.  I use lock tight when I am pressing the new shaft to be sure there is a good bond.

I have an armature that can be yours for shipping cost, if the spline making bit doesn't pan out. My email is in my profile. 

I think the free armature seems to be the best bet!   Pickup the gear and assemble, and you're on your way.

Thanks for the offer Luke.  I'll let you know how I make out with my repair.

Tom