I recently had to replace prematurely worn idler and drive gears on my LGB 21427 Ge 4/4 III "COOP" loco and thought others should be made aware. The cause was the same issue that I had with my LGB Ge 2/4 - bad positioning of the drive gear on the axle. Only half of the tooth width engaged with the spur gear of the idler. The first photo shows the replaced gears. I neglected to take a pic of the failed gears. As I mentioned in the previous post about the Ge 2/4, LGB could eliminate the issue completely by making the spur gear of the idler wider.

They actually did this on the new RhB Ge 6/6 II locos as can be seen in the second picture. (Note: after the COOP problem I had to check!)

You might want to check your Ge 4/4 III if you've got one. You're better off fixing the gears before they wear out and need replacing. It is relatively easy to move the drive gear if necessary. Just don't completely eliminate the side play of the wheelset and idler.

They actually did this on the new RhB Ge 6/6 II locos as can be seen in the second picture. (Note: after the COOP problem I had to check!)

You might want to check your Ge 4/4 III if you've got one. You're better off fixing the gears before they wear out and need replacing. It is relatively easy to move the drive gear if necessary. Just don't completely eliminate the side play of the wheelset and idler.
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