Post model & serial numbers from data plates on mower & engine. Pull lever out at backside of mower & try rolling forward & back. Also check drive belt for replacement, use Murray OEM parts.
Please post your model number of your mower as well as the model number for the engine. At least then we will be able to tell what mower you have and who made it.
Murray at this point has been made by Murray, MTD, and Husqvarna