Have a Big Hauler new in box, probably 15 yrs old, will not run over a foot in less than 1 second, it is very slow with the original transformer about 2 inches square, think it said 7 amps,  and have tried it on 3 layouts with same results. Any suggestions to help would be great as I am new in Garden Size railroading,,, was going to use this as my first garden train, but, as I said , it won't run. Also, after about 5 mins running so slow transformer cuts off hot. Any comments will be valuable to me... sincerely, Doug