· Here is the engine manual,see page 2 for mixture ratios. Also for: Type 1, Type 2, Type 3, Type 4, Type 5, Type 6, Type 7, Type 8, Type 9, Type 10. The spark plug on your MTD brand snow blower is required to ignite the fuel and air mixture that enters the engine&39;s cylinder for combustion. A properly operating carburetor is essential to a smooth running engine that is easy to start. Find all the parts you need for your Yard Machines Snowblower 31AE150-062/1998 at RepairClinic. About This Manual This manual is a 31ae150-062 manual step-by-step guide that will acquaint you with the system&39;s features and benefits.