Thanks CG1 and Phillyreading.  I have fiddled as much as possible with the position of the horn lever and I get a bit of a longer blast but now way to hold a horn sound.  I am going to look at the transformer to check the voltage boost and wipers to see if there is a build up.  I can see the result of the voltage boost in the intensity of the headlights, but I have not put my meter on the tracks yet.  I will do some testing.

Thanks

I have a new WIlliams 22109, 44 Ton Locomotive and I am operating on Lionel 027 track with a Lionel KW 190W dual side transformer. When I operate the horn lever, which works fine for the coal car whistle in my 1953 Lionel steam engine, all I get is a short burb from the Williams diesel.  Are there any wiring changes possible in the Williams to get a full horn?