Ho or n scale emgine motor

[usher42]

What size motors and how many dc does it run on

[ebtnut]

Model railroad motors are sized for the application - they aren't really "HO motors" or "N motors".  All of them in the U.S. are designed to operated on 12 volts DC.  Most modern motors only draw a quarter amp or less, so you can operate several at the same time from one power pack. 

[Doneldon]

usher-

ebtnut is absolutely correct. The choice of motor to install is driven by size more than power considerations. And by power I mean pulling power, not the electricity on which the motor runs.
                                                                                          -- D