What is the belt sizes for the lawn chief riding mower model# 13AM673G022
I need the sizes of the drive belts and the deck belt ty

Hi,
Well, these are nonstandard belts to cross into auto supply house sizes. The front variable speed belt is a 754-0280A(0.688" x 53.17"), rear is 754-0370(0625" x 48.5") and deck is 754-0371A(0.625" x 74") As you can see only the deck belt is standard. They are also Kevlar sheathed. Trying to use anything on the variable speed other than original usually results in loss of speeds.
Parts manual is available from MTD, but is too large to upload here.
Peace,
Clarke