I bought a BLI 2-8-2 Mikado around 9 years ago.
I never did anything about it, but the connection rods jam and lock up on occasion. The most recent time that it happened, I called BLI about the problem. They will repair it for $65, but the original parts are no longer available, so they would use parts from the current line of Mikados and put my shell on top of the rehabbed chassis. Fair enough, but I am too cheap at this point to spend the $65.
To free up the connecting rods in the past, I have had to remove the plastic plate that holds the driver wheels and connecting rods in place and fiddle with the driver wheels.
This time, I decided to look more closely at the problem. If you look at the first photo, a shot from the side of the loco, the area inside the green circle was where I initially thought that the problem was occurring. The rods that slide on the top and bottom of that assembly had fallen off to the side of the assembly and locked up. However, over time, as it jam and lock up occurred, I noticed that the connect rod itself was bending, as seen in the area inside the red circle.
But, now, if you look at the second photo, a shot from the bottom of the loco,I have circled a third area in blue. That square bronze bearing doesn’t stay in place with lateral movement of the wheels. The other three driver sets and their square bronze bearings hold into place on the first three driver wheel sets, but not on that rear set of driver wheels. Usually, this is not a problem, but in the event of a derailment, this excessive lateral movement causes the connecting rods to slip, jam, and lock up.
This doesn’t happen often because derailments do not occur often except in the case of operator error. But, when it happens, the connecting rods jam up and lock. And, of course, the resulting bending of that connecting rod has weakened it.
I have checked with an NMRA gauge and the driver wheelsets are all in