What Lionel left off the Polar Express K4 was the whistle shield which is located behind the steam dome where the whistle is located. Its function was to force the steam up into the air rather than blowing in the cab and blinding the engineer and fireman. You can buy a whistle shield from a company called Precision Scale. That’s what I did a few years ago when I bought one of these engines to convert over to a PRR K4 to double head with my 1330 PRR K4.
What Lionel left off the Polar Express K4 was the whistle shield which is located behind the steam dome where the whistle is located. Its function was to force the steam up into the air rather than blowing in the cab and blinding the engineer and fireman. You can buy a whistle shield from a company called Precision Scale. That’s what I did a few years ago when I bought one of these engines to convert over to a PRR K4 to double head with my 1330 PRR K4.