Fix the drive belt.
Please provide the model number when asking a question like this. Different models use different techniques. Craftsman LT1200
check to be sure the blades have free movement. usually if you have this problem it is caused from something stopping the blades from rotating therefore it stops the engine
Your switch may be bad or came disconnected. Or your PTO could have came unplugged, or it went bad.
Check your shear pins.
Two types are listed, on mulching(134149) and one hi-lift(138498.) These have the star hole in the center.
There are two blades on that model. It has mixed reviews due to placement of some features but it is attractive to some people because of the large mower deck.
why does my rider cut off when i engage the blades
A person can get an owner's manual for a Craftsman lawn tractor by contacting the Craftsman company. The phone for customer service is 1-888-331-4569.
Husqvarna
craftsman
If you are saying that the mower shuts off when you engage the blades (or put the lever for the blades in the up position) then the most common problem is a bad seat safety switch. This is located under the seat. It has two wires going to it.
to fix a sears tractor