Best way to get your old Marx Steamer to smoke again?

Any body have any tricks to get my old smoke stack to smoke again.
It will smoke a little bit if you hold the wheels off the track and turn the transformer all the way up, but in normal operation it doesn’t smoke at all.
I’ve got smoke fluid in it.

Any ideas.

Find out for sure if it is a liquid or pellet unit, that might make the difference. Smoke pellets may be what you need (They are toxic though). I’m not sure how toxic they are but I know they were discontinued in 1969.