A: Lionel often stamped the engine number on the tender chassis. Such is the case with the no. 243 engine coupled to a no. 243W tender. Your tender is also shown in the Greenberg book coupled to a no. 239 engine.
Lionel tender no. 234W
By | September 10, 2010
I acquired a 234w tender along with a 2037 engine. Both seemed to have had extensive use. The 234w I have read was included with some 2037 engines but only a few. My problem is that it is getting to be as old as myself and like myself is beginning to not work properly. It whistles but has a ratcheting sound before it does then it does whistle but only at nearly full power from a 1033 transformer. The pickups may have been previously replaced. The brushes appear to be showing uneven wear. How hard is it to replace the brushes?
Greenberg's Guide to Lionel Trains 1945-1969 also lists the 234W tender for the 2029 loco (pg. 46).