Guys:
I'm new here on the forum and to American Flyer. I recently received a number of AF engines and rolling stock from my father-in-law's estate when he passed away. My wife and I built a Christmas layout this past Christmas. One of the engines we have is the L/AF Christmas GP-9 when I think was first in the 2011 Lionel catalog. When I ran this engine, it ran much more slowly than another NKP GP-9 that we have that was made in 2005. It also could not pull as many cars. I ran both engines on the same track at the same transformer voltage, pulling the same cars. The Christmas GP-9 was considerably slower.
I have done what I can do in terms of basic cleaning and oiling per the instructions that came with the engine and recommendations that I read on this forum. My father-in-law had a large collection, so I don't think the Christmas engine was run very often. I am not very mechanical, but is there anything else I can do to check what is wrong with this engine?
Thanks for your help,
-Rick