Big Block Gear Drive On A Slant?

In a (4)gear gear drive like this originally was, one of the smaller gears is designed to transmit the load between the crank gear and cam gear, the other one is simply an idler gear as its name implies. Did you take the correct gear out of the equation...? They are different diameters and the idler may not engage to the correct depth to be used as the drive gear if you swap them.....