polar express engine wont move when smoke switch turned on?

I had the same problem with a Polar Express engine, the hot wire going into the smoke unit cover was bare and shorting out the engine. Four screws remove the boiler (easy) The wire going into the hole in the cap needed to be isolated from the metal body. Try sliding the

insulating tubing down farther so the wire doesn't touch the metal cap. You may need to carfully pry the cap off, When replacing it it has a detent that needs to be lined up so the cap will seat correctly.

where are the four screws to remove boiler????  cant find anything online to help me dissasemble engine to find the short. its a  2 8 4 burkshire 1225 polar express engine. can anyone help please?

There are two Phillips head screws in the rear and two in the front by the steam chest

Cradle the engine upside down in some towels or something to hold it  from tipping and without damaging anything, the four screws are on the bottom. Two in front and two in the rear

thank you so much, found the wires at the smoke switch touching. fixed it runs great. thank you! happy hollidays!

For anyone else wondering where the screws may be found. The locations are detailed on page 16 of the Polar Express set manual. 

if you don't have the 73-1960-250 manual Nicole is talking about, here is the link   http://www.lionel.com/media/se...ents/73-1960-250.pdf.  They are the 4 body screws shown on page 16

Here is a parts list with an exploded view of everything at the bottom of the list.

http://www.lionel.com/Products...ments/6897_combo.pdf