Help me here, the neophyte. Just bought a new Bachmann set at Cosco (Cargo King). My grandson likes to manually push the train. I asked a local train guy (i know nothing about electric trains) and he said the wheels wont roll so no damage done if he slides it along the rails. But as you likely know the wheels do roll (at least some of them), so is it still true there is no damage? he moves it pretty carefully and without a lot of downward pressure.
You would do better to get a dummy locomotive (generally easy to find on eBay) for your grandson to manually push and save the powered loco for electrical operation.
Pushing the locomotive by hand is very stressful on the gears, and can easily cause severe damage to them. It is also hard on the wheels, possibly wearing through the plating or creating flat spots that will cause poor performance when under power. Even the track can be accidently damaged beyond use by a young engineer's inadvertent actions. Allowing him to push a dummy engine does not solve the problem of teaching him the limitations of H0 trains.
Much better to get the youngster a toy train (as opposed to a model train) that has some plastic or wood track and is made to be pushed by hand.
Save the electric train for powered operation under adult supervision. Having a broken train is a big disappointment for all!
Happy RRing,
Jerry
Chances are good that there would be damage to the loco or the track. Buy him a wooden Thomas set to tie him over until he is old enough to operate them electrically.
Thanks to all 3 of you. He does have many trains and since the wheels were moving i wondered if he could damage it. Now i know. and he will just watch it now!