Tips and Tricks from MartyE .com


A look inside Lionel's Legacy GP 7 smoke unit.

There is no doubt that Legacy smoke units have come a long way from their predecessors. Along with 3 levels of smoke intensity they reliably produce a much better volume of smoke than previous Lionel smoke units.


Legacy GP7's have an issue that IMO could have been prevented with a little modification.  Unfortunately I won't cover that here but will take you on a tour of the GP7's smoke unit and give you some hints to help keep a large stream of smoke flowing from the dual stacks.  As always all work is done at your own risk!


The secret hatch.  Something you may have discovered is the panel with the 2 stacks on it lifts off the GP7.  I can get this to lift off using my finger nails to pry up from the sides.  I tilt the panel up on the end opposite the decorative horn so I can slide it out from under it,  Great care should be taken not to damage the horn.

The panel with the stacks conceals the smoke unit system.  Careful of the decorative horn when removing it.


Once removed, hopefully the gasket is still attached to the panel.  The funnel / dual stack feeder is pressed onto the smoke unit.  This feeder allows the use of 1 smoke unit to feed both stacks.  It works but unfortunately it is the weak link of the entire unit.  The biggest issue is getting fluid into the smoke unit through a small opening and down the funnel.  It would be best to fill the unit from the stack furthest from the cab as it has a shorter distance to try to get into the unit.  Also air bubbles tend to form in it preventing smoke from getting out.  Blowing down the stack can clear this but also can force fluid out of the opposite stack and all over the locomotive.

The dual stack feeder funnels smoke to both stacks. 


Because a gasket is required to seal the funnel to the lift off panel, the oily fluid eventually weakens the glue on the gasket allowing fluid to get all over most of the smoke unit below.  If you are not careful you could have an engine full of slimy fluid.  I personally would like to see either the funnel attached directly to the panel so no gasket is required or a better gasket / lip that has the funnel seat better to the stack panel.

Notice the fluid residue on the smoke unit circuit board.  Lot's of other boards to get smoke fluid on as well.


In my experience the gasket will either be coming off the panel or already off.  The glue just cannot deal with the oil we use for fluid.  I do the best I can to clean up all the parts and re-install them back on to the smoke unit.  The funnel has a round feed tube that sits directly on the smoke unit's brass fitting.  A small gasket is there as well but like the panel gasket it becomes rather gooey.

The 3 main components of the stack panel and funnel assembly.  Note the 2 pins on the stack panel and the matching holes on the gasket.  Also note the adhesive residue on the stack panel.


You may get lucky and have the gasket "stick" back on the roof panel.  But as you can see from the photo below that can be a long shot.  I usually set it atop the funnel and then re-attach the panel.  I doubt it's a great seal but due to the lack of adhesive at least I can get the panel on without it falling off and not aligning very well at all.  I may try some other adhesives to see if I can find a solution.

What a gooey mess.


After wiping down all the major components and clearing the funnel with a little air forced through you may want to fill the unit while the funnel is off.  Re-assemble the unit by putting the funnel back atop the smoke unit.  If your gasket is still attached to the stack panel carefully insert the one end under the decorative horn and then seat it onto the shell.  If the gasket is loose then I would suggest aligning it to the top of the funnel and carefully lower the stack panel down onto it.

Funnel is re-seated waiting for the gasket and stack panel.


These units smoke very well.  With a little care they will impress everyone with the volume of smoke they can produce.  I'm sure replacement gaskets are available from Lionel but I fear they will meet the same fate as the previous one, a gooey mess.  Hopefully Lionel can come up with a better funnel / panel setup. Just be careful when filling the unit. Take the panel off occasionally and make sure the majority of the fluid is going where it should be.  Hope this helps!

Email me with some feedback @

Close this window to back to!

Home What's New Media Tips and Tricks Links

Email me at